Optical fiber integrated three-photon excitation atomic gas cell probe based on optical superlens

Abstract

The present application relates to the technical field of quantum microwave measurement, and discloses a kind of optical fiber integrated three-photon excitation atom gas chamber probe based on optical superlens, including atom gas chamber, probe light input polarization maintaining optical fiber and probe light output polarization maintaining optical fiber;Atom gas chamber is integrated with probe light input collimating superlens at input end, probe light input polarization maintaining optical fiber is vertically arranged with the input end side wall surface of atom gas chamber, and the probe light output by probe light input polarization maintaining optical fiber is incident to atom gas chamber by probe light input collimating superlens;Atom gas chamber is integrated with multiple wavelength composite superlens at output end, probe light output polarization maintaining optical fiber is vertically arranged with the output end side wall surface of atom gas chamber and is on the same straight line with probe light input polarization maintaining optical fiber, and probe light is coupled to probe light output polarization maintaining optical fiber output by multiple wavelength composite superlens after being output from atom gas chamber.Output by atom gas chamber is avoided by three-photon excitation scheme photoionization effect, and the structural complexity problem caused by multi-beam integration is effectively solved.

Description

Technical Field

[0001] This invention relates to the field of quantum microwave measurement technology, and in particular, to a fiber-optic integrated three-photon excited atomic gas cell probe based on an optical superlens. Background Technology

[0002] The atomic gas cell probe is the core sensing component of an electric field measurement system based on the Rydberg effect, and its performance directly determines the sensitivity and accuracy of the measurement. To improve the practicality of the system, fiber-optic integrated atomic gas cell probes have become an important development direction.

[0003] Currently, most reported fiber-optic integrated atomic gas cell probes employ a two-photon excitation scheme. In this scheme, two laser beams of different wavelengths (e.g., 780nm and 480nm lasers are commonly used for rubidium atoms) are typically guided into the probe through a polarization-maintaining fiber. These beams are then combined and focused by a series of discrete optical elements, such as a dichroic mirror and a gradient refractive index lens, before finally entering the atomic gas cell. However, the short-wavelength lasers (e.g., 480nm) used in this scheme are prone to inducing photoionization within the atomic gas cell. This effect leads to a decrease in the neutral atom number density and the generation of parasitic charges, thus interfering with the measurement process and becoming a key factor limiting further improvements in probe sensitivity.

[0004] To address the problem of photoionization, a three-photon excitation scheme has been proposed. This scheme utilizes longer-wavelength lasers for atomic excitation, effectively avoiding the aforementioned adverse effects. However, existing three-photon excitation systems typically rely on spatial optical path construction, which includes multiple discrete optical components. This results in a large system size, complex structure, and difficult adjustment, making it difficult to meet the application requirements for probe miniaturization, integration, and portability. If the fiber-integrated design of existing two-photon excitation probes is directly applied to the three-photon excitation scheme, the need to process more beams will inevitably introduce more optical components for beam management. This will further increase the structural complexity and size of the probe, hindering the achievement of high integration. Summary of the Invention

[0005] This invention provides a fiber-optic integrated three-photon excited atomic gas cell probe based on an optical superlens. It can effectively solve the structural complexity problem caused by multi-beam integration while avoiding photoionization effect by using a three-photon excitation scheme, thereby achieving a breakthrough in probe miniaturization and high integration.

[0006] This invention provides a fiber-optic integrated three-photon excited atomic gas cell probe based on an optical superlens, comprising an atomic gas cell, a probe light input polarization-maintaining fiber, and a probe light output polarization-maintaining fiber. The input end of the atomic gas cell integrates a probe light input collimating superlens, and the probe light input polarization-maintaining fiber is arranged perpendicularly to the sidewall of the input end of the atomic gas cell. The probe light output from the probe light input polarization-maintaining fiber is incident on the atomic gas cell through the probe light input collimating superlens. The output end of the atomic gas cell integrates a multi-wavelength composite superlens, and the probe light output polarization-maintaining fiber is arranged perpendicularly to the sidewall of the output end of the atomic gas cell and is on the same straight line as the probe light input polarization-maintaining fiber. The probe light output from the atomic gas cell is coupled to the probe light output polarization-maintaining fiber through the multi-wavelength composite superlens.

[0007] Furthermore, both the probe light input collimating superlens and the multi-wavelength composite superlens are optical superlenses.

[0008] Furthermore, the optical superlens is fabricated on the side wall of the input end of the atomic gas cell using laser direct-writing optical superlens technology to form a probe light input collimating superlens; and / or the optical superlens is fabricated on the side wall of the output end of the atomic gas cell using laser direct-writing optical superlens technology to form a multi-wavelength composite superlens.

[0009] Furthermore, the optical superlens is integrated onto the input sidewall of the atomic gas cell using optical adhesive, thereby forming a probe light input collimating superlens; and / or the optical superlens is integrated onto the output sidewall of the atomic gas cell using optical adhesive, thereby forming a multi-wavelength composite superlens.

[0010] Furthermore, it also includes a polarization-maintaining fiber for adorned light input and a polarization-maintaining fiber for coupled light input; the adorned light output from the polarization-maintaining fiber for adorned light input is incident into the atomic gas cell through a multi-wavelength composite superlens, and the coupled light output from the polarization-maintaining fiber for coupled light input is incident into the atomic gas cell through a multi-wavelength composite superlens.

[0011] Furthermore, the polarization-maintaining fiber for the input of the embellished light is located directly below the polarization-maintaining fiber for the output of the probe light; the polarization-maintaining fiber for the input of the coupled light is located directly above the polarization-maintaining fiber for the output of the probe light.

[0012] Furthermore, the probe light output from the polarization-maintaining fiber is incident on the atomic gas cell through the probe light input collimating superlens to form a probe light collimated output beam. The embellishment light output from the polarization-maintaining fiber is incident on the atomic gas cell through the multi-wavelength composite superlens to form an embellishment light collimated output beam. The coupling light output from the polarization-maintaining fiber is incident on the atomic gas cell through the multi-wavelength composite superlens to form a coupling light collimated output beam. The overlapping region of the probe light collimated output beam, the embellishment light collimated output beam, and the coupling light collimated output beam is the region where the Rydberg atom is located.

[0013] Furthermore, the atomic gas chamber employs a sealed shell containing alkali metal atomic vapor.

[0014] Furthermore, the sealed shell is made of either all-glass or a mixture of silicon and glass.

[0015] Furthermore, the alkali metal atom is either a cesium atom or a rubidium atom.

[0016] The present invention has the following beneficial effects: 1. Achieving precise alignment and efficient transmission of the probe optical path, ensuring spectral signal-to-noise ratio: The input and output optical fibers of the probe light (probe light input polarization-maintaining fiber and probe light output polarization-maintaining fiber) are arranged coaxially and oppositely, forming a collinear optical path. The probe light input collimating superlens at the input end is responsible for converting the probe light from a point source into parallel light or a low-divergence beam, enabling it to pass through the atomic gas cell with minimal loss. The multi-wavelength composite superlens at the output end efficiently converges and couples the emitted probe light into the output fiber. The integrated design of "collimation-transmission-convergence" minimizes diffraction loss, scattering loss, and misalignment loss of the probe light inside the gas cell and at the interface, ensuring that the probe light signal has high intensity and quality, providing a signal-to-noise ratio guarantee for subsequent high-sensitivity photoelectric detection.

[0017] 2. Significantly improved mechanical stability and environmental robustness of the probe through integrated structure: Traditional systems use discrete optical components, which require precision brackets for fixation and adjustment, making them susceptible to optical path deviation due to temperature changes, vibration, and mechanical stress. In contrast, this invention directly fabricates the superlens onto the body of the atomic gas cell, solidifying the key optical interface and the gas cell into a single, compact module. This integrated structure eliminates the risk of relative displacement between internal components, greatly reducing the sensitivity of the entire probe to external environmental interference (such as vibration and temperature fluctuations), resulting in higher long-term stability and reliability, and making it more suitable for field applications outside the laboratory.

[0018] 3. It provides flexible space for the integration of other beams in three-photon excitation and simplifies the system: By integrating a multi-wavelength composite superlens at the output end of the atomic gas cell, its composite function can cover not only the probe beam, but also the other two coupled beams (coupled beam and embellishment beam) required for three-photon excitation. For example, the other two coupled beams can be incident from angles different from the probe beam path (such as the side) and pass through or be controlled by the multi-wavelength composite superlens, and finally achieve spatial convergence with the probe beam in the atomic gas cell. This avoids setting up complex discrete optical elements for each beam separately in the narrow probe space, and integrates the management function of multiple beams onto a planar element, which greatly simplifies the internal structure of the probe and is the key to achieving high integration of the three-photon excitation scheme.

[0019] 4. It gives the probe outstanding advantages of miniaturization and lightweight, promoting portable applications: By using an ultra-thin planar superlens to replace traditional three-dimensional discrete optical components such as lenses, prisms, and dichroic mirrors, and by utilizing its multi-functional integration characteristics, the axial length and lateral volume of the probe can be significantly reduced. This compact design makes it easier for the probe to be packaged into a miniaturized module, laying the foundation for the development of handheld and portable Rydberg atomic electric field measurement instruments.

[0020] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0021] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of the fiber-optic integrated three-photon excited atomic gas cell probe based on an optical superlens according to a preferred embodiment of the present invention; Figure 2 This is a schematic diagram of the optical signal transmission path of a fiber-optic integrated three-photon excited rubidium atom gas cell probe based on an optical superlens according to a preferred embodiment of the present invention; Figure 3 This is a schematic diagram of the energy level transition of the Rydberg state of a rubidium atom excited by three photons, according to a preferred embodiment of the present invention.

[0022] Legend: 1. Atomic gas cell; 101. Input end sidewall; 102. Output end sidewall; 2. Probe light input polarization-maintaining fiber; 201. Probe light collimated output beam; 3. Probe light output polarization-maintaining fiber; 4. Probe light input collimating superlens; 5. Multi-wavelength composite superlens; 6. Adorned light input polarization-maintaining fiber; 601. Adorned light collimated output beam; 7. Coupled light input polarization-maintaining fiber; 701. Coupled light collimated output beam; 8. Overlapping region. Detailed Implementation

[0023] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0024] like Figure 1As shown, the fiber-integrated three-photon excited atomic gas cell probe based on an optical superlens in this embodiment includes an atomic gas cell 1, a probe light input polarization-maintaining fiber 2, and a probe light output polarization-maintaining fiber 3. The input end of the atomic gas cell 1 is integrated with a probe light input collimating superlens 4. The probe light input polarization-maintaining fiber 2 is arranged perpendicularly to the input end sidewall 101 of the atomic gas cell 1. The probe light output from the probe light input polarization-maintaining fiber 2 is incident on the atomic gas cell 1 through the probe light input collimating superlens 4. The output end of the atomic gas cell 1 is integrated with a multi-wavelength composite superlens 5. The probe light output polarization-maintaining fiber 3 is arranged perpendicularly to the output end sidewall 102 of the atomic gas cell 1 and is on the same straight line as the probe light input polarization-maintaining fiber 2. The probe light is output from the atomic gas cell 1 and coupled to the probe light output polarization-maintaining fiber 3 through the multi-wavelength composite superlens 5. The atomic gas chamber 1, serving as the core sensing medium, is filled with vapor of specific metal atoms (such as rubidium and cesium) and is the site of the three-photon excitation process. The probe light and the embellishment light interact within the chamber, exciting atoms to the Rydberg state. These atoms are extremely sensitive to the microwave electric field being measured, responding to the electric field by altering the absorption characteristics of the probe light, thus achieving electromagnetic field sensing. The probe light input polarization-maintaining fiber 2 transmits and maintains the polarization state of the probe light, guiding the probe light from an external laser (such as 780nm light in a rubidium atom system) to the probe with a stable polarization state. Its polarization-maintaining characteristic is crucial because many atomic energy level transitions are selective for light polarization; stable polarization is a prerequisite for ensuring consistent excitation efficiency and measurement repeatability. The probe light output polarization-maintaining fiber 3 collects and transmits the emitted probe light, receiving and guiding the probe light signal, which has already interacted with atoms and carries microwave electric field information, to an external photodetector. Its polarization-maintaining characteristic also helps maintain signal quality in the back-end signal processing. The probe light input collimating superlens 4, used for beam shaping (collimation), is integrated close to the input end of the atomic gas cell 1. It rapidly shapes the strongly divergent spherical wave emitted from the probe light input polarization-maintaining fiber 2 into a parallel or low-divergence beam. This avoids beam diffusion and ensures that the probe light maintains a small spot size as it travels through the entire length of the gas cell, thereby achieving higher spatial overlap efficiency with the embellishment light and maintaining high power density. This lays the foundation for subsequent coupling, as the collimated beam is a prerequisite for efficient coupling into the probe light output polarization-maintaining fiber 3.The multi-wavelength composite superlens 5, used for multifunctional beam management (focusing and beam combining / splitting), is one of the core components for achieving high integration. Integrated at the output end of the gas cell, it is a planar microstructure that applies different phase modulations to light of different wavelengths, thereby achieving the following composite functions: For the probe light (e.g., 780nm), it acts as a focusing lens, efficiently converging the collimated probe light after passing through the gas cell onto the core of the polarization-maintaining fiber 3 at the probe light output, achieving low-loss coupling; For the embellishment light (e.g., 776nm), it acts as a collimating lens (or a lens confocal with the probe light), collimating the diverging light emitted from the polarization-maintaining fiber 6 from the embellishment light input, causing it to propagate in the gas cell in a parallel and opposite manner to the probe light, forming a perfect spatial overlap and greatly optimizing the three-photon excitation efficiency. The polarization-maintaining fiber 6, used for inputting the embellished light, transmits and maintains the polarization state of the embellished light. It guides the third excitation light (coupled light, such as 1260nm) to the probe. This fiber is deployed separately from the polarization-maintaining fiber 2, achieving physical separation of the optical paths and avoiding the use of complex and high-loss fiber combiners externally or inside the probe. The polarization-maintaining fiber 2 and the polarization-maintaining fiber 3, one for inputting and one for outputting the probe light, together with the collimating superlens 4 and the multi-wavelength composite superlens 5, form a high-precision, low-loss collinear transmission optical path. The collimating superlens 4 ensures that the light enters the atomic gas cell 1 in the optimal form, while the multi-wavelength composite superlens 5 ensures that the light is collected with the highest efficiency. This symmetrical design of front-end collimation and back-end focusing maximizes the utilization efficiency of the probe light, laying the foundation for high signal-to-noise ratio measurements. The matching and coordination of the probe light input collimating superlens 4, the multi-wavelength composite superlens 5, and the embellishment light input polarization-maintaining fiber 6 to form the excitation optical path space is the key to realizing three-photon excitation. The multi-wavelength composite superlens 5 is the center of the synergistic effect. Utilizing its chromatic aberration characteristics, it simultaneously and precisely manages the two light paths: one is the forward-propagating probe light, and the other is the reverse-propagating embellishment light. This ensures that the two beams remain highly parallel and spatially overlapping in the interaction region of the entire atomic gas chamber 1, thereby achieving optimal excitation efficiency and avoiding the placement of any discrete optical components inside the gas chamber, thus achieving a high degree of integration of internal components. The probe light input collimating superlens 4 and the multi-wavelength composite superlens 5 are directly integrated on the side wall of the atomic gas chamber 1 (such as the glass wall). Together with the optical fibers (probe light input polarization-maintaining fiber 2, probe light output polarization-maintaining fiber 3, and embellishment light input polarization-maintaining fiber 6), they form a fully solidified optical module. All optical interfaces are permanently and precisely fixed. This integrated design makes the entire probe highly immune to external vibrations, temperature fluctuations, and other interferences, achieving extremely high mechanical and thermal stability. It solves the pain point of traditional space optical path systems requiring frequent calibration.By directly integrating functionally defined optical fibers (probe light input polarization-maintaining fiber 2, probe light output polarization-maintaining fiber 3, embellishment light input polarization-maintaining fiber 6, and coupling light input polarization-maintaining fiber 7) with highly integrated superlenses (probe light input collimating superlens 4 and multi-wavelength composite superlens 5) into the atomic gas cell 1, each component performs its own function while working closely together. With the multi-wavelength composite superlens 5 as the key node, not only is the transmission and reception management of the probe light signal efficiently completed, but the perfect spatial matching of the probe light and embellishment light within the gas cell is also cleverly achieved. Thus, a high-performance three-photon excitation process is efficiently realized within an extremely compact and robust package. This allows the probe to achieve miniaturization, high stability, and high reliability while retaining the inherent advantages of the three-photon excitation scheme (such as avoiding photoionization). This represents a significant advancement towards the practical application of Rydberg atomic sensors. This invention is based on an optical superlens-integrated three-photon excitation atomic gas cell probe, which does not use short-wavelength lasers (such as 510nm or 480nm), thus avoiding the performance degradation caused by photoionization. The three-photon beam is controlled by an optical superlens, and the optical superlens can be fabricated on the sidewall of the atomic gas cell through laser direct writing process, resulting in a high degree of integration of the atomic gas cell probe.

[0025] This invention presents a fiber-optic integrated three-photon excitation atomic gas cell probe based on optical superlenses, providing a highly integrated probe structure. Two optical superlenses with different functions (probe light input collimating superlens 4 and multi-wavelength composite superlens 5) are directly integrated onto the input sidewall 101 and output sidewall 102 of the atomic gas cell 1, respectively. The input and output optical fibers (probe light input polarization-maintaining fiber 2 and probe light output polarization-maintaining fiber 3) are coaxially aligned, forming a collinear optical path. The probe light input collimating superlens 4 at the input end converts the probe light from a point source into parallel light or a low-divergence beam, allowing it to pass through the atomic gas cell 1 with minimal loss. The multi-wavelength composite superlens 5 at the output end efficiently converges and couples the emitted probe light into the output fiber. This integrated "collimation-transmission-convergence" design minimizes diffraction loss, scattering loss, and misalignment loss of the probe light inside the gas cell and at the interface, ensuring high intensity and quality of the probe light signal and providing a signal-to-noise ratio guarantee for subsequent high-sensitivity photoelectric detection. Traditional systems use discrete optical components, which require precision supports for fixation and adjustment. They are susceptible to optical path deviation due to temperature changes, vibrations, and mechanical stress. In contrast, this invention directly fabricates the superlens onto the body of the atomic gas cell 1, solidifying the critical optical interface and the gas cell into a single, compact module. This integrated structure eliminates the risk of relative displacement between internal components, greatly reducing the sensitivity of the entire probe to external environmental interference (such as vibration and temperature fluctuations). It possesses higher long-term stability and reliability, making it more suitable for field applications outside the laboratory. By integrating a multi-wavelength composite superlens 5 at the output end of the atomic gas cell 1, its composite function can cover not only the probe light but also the two additional coupling beams (coupled beams and embellishment beams) required for three-photon excitation. For example, the two additional coupling beams can be incident from angles different from the probe light path (such as the side) and pass through or be controlled by the multi-wavelength composite superlens 5, ultimately achieving spatial convergence with the probe light within the atomic gas cell 1. This avoids the need to set up complex discrete optical elements for each beam separately in the confined probe space, integrating the management function of multiple beams onto a single planar element, greatly simplifying the probe's internal structure, which is key to achieving high integration in the three-photon excitation scheme. By using an ultra-thin planar superlens to replace traditional three-dimensional discrete optical elements such as lenses, prisms, and dichroic mirrors, and utilizing its multifunctional integration characteristics, the axial length and lateral volume of the probe are significantly reduced. This compact design makes it easier to package the probe into a miniaturized module, laying the foundation for the development of handheld, portable Rydberg atomic electric field measurement instruments.This invention relates to a fiber-optic integrated three-photon excitation atomic gas cell probe based on an optical metalens. Utilizing the planar and customizable characteristics of the optical metalens, it is integrated with the atomic gas cell 1. This design first establishes a robust and efficient transmission path for the probe light, ensuring the quality of the reference signal during the sensing process. Furthermore, the high degree of structural integration significantly improves the probe's mechanical stability and environmental adaptability. The multi-wavelength composite metalens 5 at the output end cleverly solves the problem of managing the space of multiple beams in three-photon excitation, providing a path to achieve high integration and functional complexity for the entire system. Ultimately, these advantages work together to enable the probe to achieve miniaturization, lightweight design, and high robustness while maintaining and even improving performance (avoiding photoionization). This effectively overcomes the shortcomings of existing technologies and provides hardware support for the Rydberg atomic sensor to move from the laboratory platform to field application.

[0026] like Figure 1As shown, in this embodiment, both the probe light input collimating superlens 4 and the multi-wavelength composite superlens 5 are optical superlenses. Traditional lenses rely on optical path accumulation to modulate the wavefront, and their thickness and curvature are the physical basis for the realization of the function, resulting in the element necessarily having a three-dimensional volume. This invention uses an optical superlens, which, as a planar optical element, modulates the phase through an artificial structure at the subwavelength scale, and can achieve complete optical functions at a thickness much smaller than the wavelength. Replacing the two core lenses with optical superlenses allows the entire probe's optical system to be transformed from a traditional three-dimensional stacked structure to a quasi-two-dimensional planar structure, directly leading to a significant reduction in the probe's axial dimensions, laying the physical foundation for realizing the miniaturized, chip-level integrated atomic gas cell 1 probe. Traditional spherical lenses have limited functionality (e.g., focusing or collimating only) and suffer from unavoidable chromatic aberration (different wavelengths have different focal lengths). In contrast, the phase distribution of the optical superlens of this invention can be arbitrarily customized by the designer. For the probe light input collimating superlens 4, it can be designed as an ideal aspherical or even a more complex wavefront shaper, achieving a better collimation effect than traditional GRIN lenses or spherical lenses. For the multi-wavelength composite superlens 5, two distinct optical functions (e.g., efficient focusing of 780nm light and efficient collimation of 1260nm light) can be independently designed and implemented on the same plane and at the same physical location for two light wavelengths, probe light (e.g., 780nm) and coupling light (e.g., 1260nm). This multifunctional integration is difficult to achieve with any traditional single refractive lens or diffractive element, simplifying the optical path and avoiding the alignment difficulties and energy losses caused by using multiple discrete elements for beam combining. Because optical superlenses are extremely thin planar structures, they can be directly fabricated on the glass wall surface of atomic gas chamber 1 using micro-nano fabrication techniques (such as laser direct writing), achieving monolithic integration of optical components and the gas chamber body. This eliminates all mechanical connection interfaces caused by the need for separate fixing and adjustment of discrete components such as lenses and prisms in traditional solutions. The probe as a whole becomes a robust single unit, extremely insensitive to deformation caused by vibration, impact, and temperature changes. The optical path alignment is permanently fixed, greatly improving the long-term stability and environmental adaptability of the product and meeting the needs of field applications.

[0027] like Figure 1As shown, in this embodiment, an optical superlens is fabricated on the input sidewall 101 of the atomic gas cell 1 using laser direct-writing optical superlens technology, forming a probe light input collimating superlens 4; and / or an optical superlens is fabricated on the output sidewall 102 of the atomic gas cell 1 using laser direct-writing optical superlens technology, forming a multi-wavelength composite superlens 5. Laser direct-writing technology directly grows the optical functional surface (optical superlens) on the substrate of the atomic gas cell 1 in the form of a micro / nano structure, integrating the optical element with the gas cell body into a single, complete solid-state device. This eliminates independent assembly steps and all the resulting alignment errors and performance inconsistencies. The optical superlens structure is an inseparable part of the surface of the atomic gas cell 1, and both have the same coefficient of thermal expansion. The optical alignment relationship is determined once and permanently during the manufacturing process; therefore, the probe is inherently immune to vibration, shock, and temperature changes, resulting in a qualitative leap in its mechanical stability and long-term operational reliability, making it particularly suitable for applications in harsh environments or on mobile platforms. Since there is no need to design separate brackets, fixtures, and packaging structures for the lens, the number of parts in the entire probe is reduced to a minimum, simplifying the physical structure and packaging process of the probe. The simpler structure means lower material costs, shorter assembly time, higher production consistency and yield, which is conducive to the low cost and large-scale production of the final product.

[0028] like Figure 1 As shown, in this embodiment, the optical superlens is integrated onto the input sidewall 101 of the atomic gas cell 1 using optical adhesive, thereby forming the probe light input collimating superlens 4; and / or the optical superlens is integrated onto the output sidewall 102 of the atomic gas cell 1 using optical adhesive, thereby forming the multi-wavelength composite superlens 5. The optical superlens is integrated onto the sidewall of the atomic gas cell 1 using optical adhesive, decoupling the manufacturing of the optical superlens from the manufacturing of the atomic gas cell 1. The optical superlens can be mass-produced on a dedicated substrate (such as a glass plate) as an independent planar optical element, and its optical performance can be tested and screened separately. Qualified optical superlenses are then integrated into the atomic gas cell 1 through adhesive bonding. This modular strategy of separating and then combining reduces process complexity. Even if individual defects occur during the bonding process, only the atomic gas cell 1 or the optical superlens is lost, rather than a completed integrated body. This is beneficial for improving overall production yield and flexibility, and is particularly suitable for R&D stages where the superlens manufacturing process is not yet fully mature or where frequent lens design changes are required. Optical adhesive bonding, as a mature and mild room-temperature process, avoids the technical risks of direct micro-nano fabrication on the delicate and potentially fragile atomic gas chamber 1, and provides a more robust and easier-to-implement integration path, enabling the rapid prototyping and realization of technical solutions utilizing the excellent optical properties of superlenses.

[0029] like Figure 1 and Figure 2As shown, this embodiment also includes a polarization-maintaining fiber 6 for the input of adorned light and a polarization-maintaining fiber 7 for the input of coupled light. The adorned light output from the polarization-maintaining fiber 6 is incident on the atomic gas cell 1 through a multi-wavelength composite superlens 5, and the coupled light output from the polarization-maintaining fiber 7 is incident on the atomic gas cell 1 through the multi-wavelength composite superlens 5. In addition to the detection optical path, this invention integrates the polarization-maintaining fiber 6 for the input of adorned light and the polarization-maintaining fiber 7 for the input of coupled light, and both of these light paths are incident on the atomic gas cell 1 through the same multi-wavelength composite superlens 5. The three independent optical fibers—the polarization-maintaining fiber 2 for the input of detection light, the polarization-maintaining fiber 6 for the input of adorned light, and the polarization-maintaining fiber 7 for the input of coupled light—completely cover all laser wavelengths required for three-photon excitation, replacing the short-wavelength two-photon excitation (such as 480nm for rubidium atoms) that is prone to photoionization in traditional schemes. This fundamentally eliminates the core problem of decreased atomic number density and parasitic electric field interference caused by photoionization, laying the physical foundation for the probe to achieve long-term stable and high-sensitivity microwave electric field measurement. The multi-wavelength composite superlens 5 achieves efficient spatial beam combining and control of multiple beams, resulting in high integration. The polarization-maintaining fiber 6 for the embellished light input and the polarization-maintaining fiber 7 for the coupled light input are not introduced separately from other directions, but share the same multi-wavelength composite superlens 5 with the output path of the polarization-maintaining fiber 3 for the probe light output. This multi-wavelength composite superlens 5 is designed as a multifunctional planar optical element, capable of simultaneously and precisely controlling these three beams of light with different wavelengths and incident angles. For example, the multi-wavelength composite superlens 5 can collimate the reverse-propagating polarization-maintaining fiber 6 for the embellished light input and the polarization-maintaining fiber 7 for the coupled light input, achieving perfect spatial overlap with the forward-propagating probe light within the atomic gas cell 1. This design replaces multiple dichroic mirrors, filters, and lenses that might be required in traditional solutions with a single ultrathin element, greatly simplifying the probe's internal structure and facilitating probe miniaturization. By employing a multi-fiber discrete input structure, the complexity and insertion loss of the pre-fiber combiner are avoided. Instead of using a fiber wavelength division multiplexer for spatial beam combining at the probe end, the three laser beams are combined at the probe end. This avoids the use of complex and expensive fiber combiners, which introduce significant insertion loss and alignment difficulties, especially for lasers with large wavelength differences. Direct use of discrete fiber input ensures that each beam can be transmitted to the probe with minimal loss, and the most complex task of beam combining is entrusted to the precisely designed multi-wavelength composite superlens 5, improving the overall optical power utilization efficiency and reliability of the system.A clear optical path architecture was established, realizing the separation and coordination of optical path functions and forming a clear division of optical path labor. The input end sidewall 101 is dedicated to the input of probe light, ensuring the purity and efficient injection of the main signal light. The output end sidewall 102 becomes the functional center for multi-wavelength management, while also undertaking the collection and output of probe light, as well as the input collimation of embellishment light and coupling light. This architecture has a clear logic, avoiding congestion and mutual interference caused by multiple light inputs at one end of the air cell, which is conducive to optical design optimization and subsequent packaging implementation.

[0030] like Figure 1 and Figure 2 As shown, in this embodiment, the polarization-maintaining fiber 6 for the input of the embellished light is located directly below the polarization-maintaining fiber 3 for the output of the probe light; the polarization-maintaining fiber 7 for the input of the coupled light is located directly above the polarization-maintaining fiber 3 for the output of the probe light. The three fibers are arranged symmetrically in space with the polarization-maintaining fiber 3 for the output of the probe light as the center, providing the optimal physical basis for the multi-wavelength composite superlens 5 to achieve efficient and symmetrical optical field control. One of the core functions of the multi-wavelength composite superlens 5 is to simultaneously collimate or focus the light emitted from these three fibers. The symmetrical arrangement of the polarization-maintaining fiber 6 for the input of the embellished light and the polarization-maintaining fiber 7 for the input of the coupled light with the polarization-maintaining fiber 3 for the output of the probe light provides a highly symmetrical incident light field condition for the design of the optical superlens. This allows the phase distribution design of the optical superlens to be optimized into a symmetrical form, thereby enabling the efficient processing of these two side-incident beams with the same optical quality and minimal aberrations. Asymmetrical arrangement leads to complex optical aberrations that are difficult to correct simultaneously with a single lens, while this symmetrical layout is the simplest and optimal solution for achieving high-performance composite functions. The two excitation and detection beams, the embellished light input polarization-maintaining fiber 6 and the coupled light input polarization-maintaining fiber 7, form perfectly coplanar and overlapping optical paths within the atomic gas cell 1, maximizing excitation efficiency. This symmetrical arrangement, one above the other, after being modulated by the multi-wavelength composite superlens 5, ensures that the embellished light input polarization-maintaining fiber 6 and the coupled light input polarization-maintaining fiber 7 are incident on the atomic gas cell 1 at symmetrical angles, forming a symmetrical optical path in a vertical plane with the collinear detection beam path. This ensures that the three beams achieve optimal coplanarity and spatial overlap within the interaction region of the atomic gas cell 1, creating ideal conditions for the three-photon excitation process and maximizing the efficiency of atom excitation to the Rydberg state, thereby directly improving the signal strength and sensitivity of microwave measurements. Arranging the three fibers tightly longitudinally (top, middle, and bottom), rather than laterally spread out or in other two-dimensional distributions, maximizes space utilization and minimizes the cross-sectional size of the probe output end, thus facilitating the miniaturization and micro-miniaturization of the probe.

[0031] like Figure 1 and Figure 2As shown, in this embodiment, the probe light output from the probe light input polarization-maintaining fiber 2 is incident on the atomic gas cell 1 through the probe light input collimating superlens 4 to form a probe light collimated output beam 201. The embellishment light output from the embellishment light input polarization-maintaining fiber 6 is incident on the atomic gas cell 1 through the multi-wavelength composite superlens 5 to form an embellishment light collimated output beam 601. The coupling light output from the coupling light input polarization-maintaining fiber 7 is incident on the atomic gas cell 1 through the multi-wavelength composite superlens 5 to form a coupling light collimated output beam 701. The overlapping region 8 of the probe light collimated output beam 201, the embellishment light collimated output beam 601, and the coupling light collimated output beam 701 is the region where Rydberg atoms are located. Three-photon excitation is a nonlinear optical process whose efficiency strongly depends on the light intensity (power density) of each participating beam. By collimating the probe beam 201, the embellishment beam 601, and the coupling beam 701 into collimated beams, maintaining a small and stable spot size in the propagation direction, extremely high power density is obtained and maintained within the overlapping region 8. This ensures that atoms are efficiently excited to Rydberg states within this specific region, generating a sufficiently strong optical signal (such as changes in probe light absorption) for detecting microwave electric fields. Defining the overlapping region 8 as the area where Rydberg atoms resides precisely limits the effective sensing area of ​​the probe to the space illuminated by the three beams. This allows for precise control of the interaction between the microwave electric field and the atoms, avoiding signal ambiguity caused by excessively large or unclear spot sizes, thus facilitating probe performance optimization. For example, the overlapping region 8 can be intentionally positioned away from the gas chamber wall to reduce the adverse effects of wall effects (such as charge accumulation and collisional relaxation) on Rydberg atoms, thereby improving measurement accuracy and stability. The formation of the collimated output beam directly verifies the successful realization of the functions of the probe light input collimating superlens 4 and the multi-wavelength composite superlens 5. In particular, the multi-wavelength composite superlens 5 can simultaneously collimate embellishment and coupling beams of different wavelengths emitted from different positions (different optical fibers), highlighting its powerful capabilities as a multifunctional planar optical element. The perfect spatial overlap of the three collimated beams is the ultimate manifestation of the coordinated work of the entire system (including the spatial arrangement of optical fibers and the phase design of the optical superlens). Since the probe light collimated output beam 201, the embellishment light collimated output beam 601, and the coupling light collimated output beam 701 are all collimated, the longitudinal dimension and spatial morphology of the resulting overlapping region 8 are relatively stable in the propagation direction. Regardless of the movement of the atoms within the atomic gas chamber 1, as long as they pass through this overlapping region 8, they will experience a basically consistent light field intensity. This spatial uniformity ensures that the generated optical signal (probe light absorption) mainly reflects the intensity of the microwave electric field, rather than fluctuations caused by the randomness of atomic positions, thereby improving the consistency and reliability of the measurement signal and reducing the background noise.

[0032] like Figure 1and Figure 2 As shown, in this embodiment, the atomic gas chamber 1 is a sealed shell containing alkali metal atomic vapor. Alkali metal atoms (such as rubidium and cesium) have discrete energy level structures, and their Rydberg states are extremely sensitive to microwave electric fields. The alkali metal atomic vapor maintained at a certain pressure inside the sealed shell provides the necessary interaction medium for achieving three-photon excitation through probe light, embellishment light, and coupling light, thus accommodating atoms from the ground state to the high Rydberg state. Sealing the alkali metal inside the sealed shell isolates it from external environmental interference, preventing chemical reactions between the alkali metal atoms and atmospheric oxygen, water vapor, etc., which could lead to failure. This ensures the long service life of the probe, maintains the stability of the atomic vapor pressure inside the cavity, and avoids disturbances to atomic energy levels and transition spectral lines caused by changes in airflow and pressure. This controlled and pure atomic environment is the basis for obtaining stable and repeatable atomic spectral signals (such as electromagnetically induced transparent EIT signals), thereby ensuring the accuracy, traceability, and self-calibration capability of microwave electric field measurement results. The optical superlens is directly fabricated or bonded to the sidewall of atomic vapor chamber 1. The sealed shell is not only a container but also serves as the mechanical platform and substrate of the optical system. Its flat sidewall provides the physical basis for the integration of the superlens, tightly combining the sensing function (atomic vapor) and the optical path guiding function (optical superlens) into a single solid-state device. This is a structural guarantee for achieving high integration and high stability of the probe. The types of alkali metal atoms loaded (such as rubidium-85, rubidium-87, and cesium-133) directly determine the specific wavelength of the laser required for the three-photon excitation path (such as combinations of 780nm, 776nm, and 1260nm). The physical dimensions of the shell (especially the optical path length) and the operating temperature (which affects the atomic vapor pressure) jointly determine key parameters such as the atomic number density, optical thickness, and collision relaxation rate. These will directly affect the core performance indicators of the probe, such as sensitivity, dynamic range, and bandwidth.

[0033] In this embodiment, the sealed housing is made of either all-glass or a mixture of silicon and glass. Whether entirely or partially glass, its core function is to provide a high-transmittance window for three-photon excited multi-path lasers (e.g., 780nm, 776nm, 1260nm). It possesses excellent optical transparency in the visible and near-infrared bands, allowing the probe light, embellishment light, and coupling light to pass through the housing wall with extremely low loss, enter the gas chamber, interact with atoms, and efficiently emit the information-carrying probe light. The glass material (e.g., borosilicate glass) is chemically inert, enabling it to coexist stably with reactive alkali metal atoms (e.g., rubidium, cesium) vapors for extended periods without violent chemical reactions. This ensures stable atomic vapor pressure within the gas chamber and prevents the alkali metals from being consumed due to reactions with the container walls, thus ensuring a long probe lifespan and long-term stability of measurement parameters. Silicon, after forming an oxide layer on its surface, also exhibits good chemical stability. Whether integrating optical superlenses via laser writing or adhesive bonding, a smooth, flat substrate compatible with micro / nano fabrication processes is required. Glass is one of the most mature and ideal substrate materials in the field of micro / nano optics, possessing high surface quality that meets the processing or bonding requirements of optical superlenses. Using a silicon-glass hybrid material, with silicon as the structural framework and glass as the optical window, can similarly ensure the integration of the superlens onto the glass window. Glass exhibits excellent hermeticity, effectively maintaining the high vacuum or buffer gas environment required inside the atomic chamber 1, preventing external gas infiltration. Employing a silicon-glass hybrid material (such as through anodic bonding) is a mature technology for manufacturing micro-cells in the MEMS (Micro-Electro-Mechanical Systems) field, forming a robust and long-term reliable vacuum seal. This reliable seal is a prerequisite for maintaining atomic energy levels free from impact broadening, ensuring spectral linewidth, and maintaining measurement accuracy. Silicon-glass hybrid materials offer potential advantages in miniaturization and mass production. The introduction of silicon allows for precise control of the internal dimensions and geometry of the gas chamber using mature silicon micromachining technologies (such as photolithography and etching), enabling extreme miniaturization of the gas chamber structure. At the same time, this technology has the potential for wafer-level mass production, which can significantly reduce the manufacturing cost of a single gas chamber, paving the way for the eventual commercialization and widespread adoption of the probe.

[0034] In this embodiment, the alkali metal atom is either cesium or rubidium. Cesium and rubidium atoms are the most thoroughly studied alkali metal atoms in atomic physics. Their energy level structures (including the ground state, excited states, and Rydberg states) have been precisely measured, and related data (such as energy level positions, transition wavelengths, and dipole matrix elements) are very complete. This provides a solid theoretical basis for accurately designing the three-photon excitation path (such as determining the specific wavelengths of the probe, embellishment, and coupling light), ensuring that the entire probe's working principle is based on a reliable and predictable physical foundation. Rubidium and cesium can generate sufficiently high atomic vapor pressures at relatively low temperatures (e.g., tens of degrees Celsius), thus providing a sufficient number of atoms in the gas chamber as the sensing medium. This eliminates the need for extreme heating or cooling of the gas chamber, allowing the probe to operate normally at near-room temperature. This simplifies the system's thermal management design, reduces power consumption, and facilitates probe miniaturization, portability, and practical application. For cesium and rubidium atoms, there are multiple possible three-photon excitation paths that can excite from the ground state to different Rydberg states. For example, for rubidium atoms, common pathways include 5S¹ / ² → 5P³ / ² (780 nm) → 5D⁵ / ² (776 nm) → nF or nS (≈1260 nm). This abundance of energy levels allows for the selection and optimization of the most suitable excitation channel based on specific needs (such as the desired Rydberg principal quantum number n, avoiding interference levels, laser availability, etc.) to balance sensitivity, linearity, and system complexity. The characteristic wavelengths corresponding to rubidium and cesium atoms (such as 780 nm and 776 nm for rubidium, and 852 nm and 794 nm for cesium) perfectly match the highly mature semiconductor laser technology. Choosing cesium or rubidium ensures that the core light source required for the probe is readily available from the market and has stable performance, reducing the difficulty, cost, and maintenance requirements of system development.

[0035] In this embodiment, the probe light input polarization-maintaining fiber 2, the probe light output polarization-maintaining fiber 3, and the embellishment light input polarization-maintaining fiber 6 all use Nufern PM630-HP fiber. The specific fiber model is chosen, and its key performance parameters (such as a 630nm cutoff wavelength and high power tolerance (HP)) are highly matched to the optical path requirements of the three-photon excitation scheme of this invention. For example, the fiber can maintain single-polarization mode transmission for wavelengths such as 780nm and 776nm, ensuring matching with the polarization selectivity required for atomic energy level transitions. This is a prerequisite for obtaining stable and repeatable excitation efficiency. Simultaneously, its high power (HP) characteristic ensures that it can withstand the certain laser power required for three-photon excitation without producing nonlinear effects or damage, thereby guaranteeing the reliability and long-term stability of the probe operation. The probe light input polarization-maintaining fiber 2, the probe light output polarization-maintaining fiber 3, and the embellishment light input polarization-maintaining fiber 6 all use the same type of fiber, which simplifies material management and integration process. When assembling the probe, there is no need to prepare and distinguish multiple fibers for different optical paths, reducing assembly complexity. Using the same type of fiber can ensure that the optical characteristics (such as mode field diameter and numerical aperture) of different optical paths are consistent, which is beneficial to optimizing the coupling efficiency with the optical superlens and reducing the system errors introduced by component differences, thereby improving the consistency of the final product performance.

[0036] In this embodiment, the polarization-maintaining fiber 7 for the coupling light input is a Nufern PS-PM980 fiber. In the three-photon excitation scheme (taking rubidium atoms as an example), the coupling light wavelength may be 1260nm, etc. These wavelengths are all within the optimal operating window of the fiber design. The fiber has low transmission loss, good mode field characteristics, and stable polarization-maintaining performance in this band, ensuring that the coupling light can be transmitted to the atomic gas cell 1 with the highest fidelity and efficiency. This is a key link in achieving efficient and stable three-photon excitation. The probe light and the embellishment light use fibers suitable for the 630nm cutoff wavelength, while the coupling light uses a fiber suitable for 980nm. This reflects the design concept of selecting the most suitable specialized fiber according to the specific wavelength of each laser path, avoiding the performance compromise that may occur in some optical paths when using a single fiber (e.g., for longer wavelength coupling light, a 630nm cutoff wavelength fiber may not be the optimal choice), thereby optimizing the overall optical transmission performance at the system level. Key parameters such as the beat length of polarization-maintaining fiber are related to wavelength. Nufern's PS-PM980 fiber is optimized for a specific wavelength range and can provide an excellent polarization extinction ratio in this band. For atomic energy level transitions, the correct optical polarization state is crucial. Choosing a dedicated polarization-maintaining fiber with wavelength matching for this path of light ensures that the coupled light is incident on the atomic gas cell 1 with the required stable linear polarization state, which guarantees precise matching with the selection rules of atomic energy levels, thereby maintaining high excitation efficiency and measurement reliability.

[0037] In implementation, a fiber-optic integrated three-photon excited atomic gas cell probe based on an optical superlens is provided, such as... Figure 1 As shown, it includes a probe light input polarization-maintaining fiber 2, a probe light output polarization-maintaining fiber 3, a probe light input collimating superlens 4, a decorative light input polarization-maintaining fiber 6, a coupling light input polarization-maintaining fiber 7, a multi-wavelength composite superlens 5, and an atomic gas cell 1.

[0038] The probe light input polarization-maintaining fiber 2 and the probe light output polarization-maintaining fiber 3 are aligned on the same straight line and perpendicular to the glass sidewalls of the atomic gas chamber 1 (input sidewall 101 and output sidewall 102). The probe light input collimating superlens 4 has probe light collimation function, and the multi-wavelength composite superlens 5 has multi-wavelength collimation function for probe light, embellishment light, and coupling light. Both the probe light input collimating superlens 4 and the multi-wavelength composite superlens 5 are optical superlenses. The integration of the optical superlenses with the atomic gas chamber 1 can be achieved by optical adhesive bonding or by fabricating them on the glass sidewalls (input sidewall 101 and output sidewall 102) of the atomic gas chamber 1 using laser direct-writing optical superlens technology.

[0039] The optical signal transmission path is as follows: the probe light output from the probe light input polarization-maintaining fiber 2 passes through the probe light input collimating superlens 4 and enters the atomic gas cell 1, then is coupled through the multi-wavelength composite superlens 5 and output to the probe light output polarization-maintaining fiber 3. The embellishment light output from the embellishment light input polarization-maintaining fiber 6 passes through the multi-wavelength composite superlens 5 and enters the atomic gas cell 1. The coupling light output from the coupling light input polarization-maintaining fiber 7 passes through the multi-wavelength composite superlens 5 and enters the atomic gas cell 1.

[0040] Atomic gas chamber 1 is a sealed shell containing alkali metal atomic vapor. The shell material can be all-glass, a mixture of silicon and glass, etc., and the alkali metal atoms can be cesium atoms, rubidium atoms, etc. Taking the rubidium atomic gas chamber as an example, the probe light wavelength is 780nm, the embellishment light wavelength is 776nm, and the coupling light wavelength is 1260nm. Figure 2This diagram illustrates the optical signal transmission path of the fiber-integrated three-photon excited rubidium atom gas cell probe based on an optical superlens according to the present invention. The probe light input polarization-maintaining fiber 2, probe light output polarization-maintaining fiber 3, and embellishment light input polarization-maintaining fiber 6 are all Nufern PM630-HP models. The probe light input collimating superlens 4 operates at a wavelength of 780nm, and the beam waist diameter of the probe light collimated output beam 201 is 500μm. The coupling light input polarization-maintaining fiber 7 is a Nufern PS-PM980 model. The multi-wavelength composite superlens 5 operates at three wavelengths: 780nm, 776nm, and 1260nm. The beam waist diameter of the embellishment light 776nm collimated output beam is 500μm, and the beam waist diameter of the coupling light 1260nm collimated output beam is 800μm. The overlapping region 8 of the probe light collimated output beam 201, the embellishment light collimated output beam 601, and the coupling light collimated output beam 701 represents the region where Rydberg atoms are located. The polarization-maintaining fiber 6 for the input of the embellished light is located 250 μm directly below the polarization-maintaining fiber 3 for the output of the probe light. The polarization-maintaining fiber 7 for the input of the coupling light is located 400 μm directly above the polarization-maintaining fiber 3 for the output of the probe light.

[0041] Figure 3 This diagram illustrates the energy level transitions of a rubidium atom in a Rydberg state excited by three photons. The probe light excites the rubidium atom from the ground state |5S1 / 2, F=2> to the intermediate state |5P3 / 2, F=3>. The adorned light further excites the rubidium atom from the intermediate state |5P3 / 2, F=3> to the adorned state |5D5 / 2, F=4>. The coupling light further excites the rubidium atom from the adorned state |5D5 / 2, F=4> to the Rydberg state. Typical Rydberg states include nF, nG, etc., where n represents the principal quantum number, which typically ranges from 40 to 80.

[0042] As can be seen from the above embodiments, the fiber-optic integrated three-photon excited atomic gas cell probe based on optical superlenses of the present invention has high integration and does not use short-wavelength lasers.

[0043] Matters not covered in this invention are common knowledge.

[0044] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0045] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

[0046] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A fiber-optic integrated three-photon excited atomic gas cell probe based on an optical superlens, characterized in that, It includes an atomic gas cell (1), a probe light input polarization-maintaining fiber (2), and a probe light output polarization-maintaining fiber (3); The input end of the atomic gas chamber (1) is integrated with a probe light input collimating superlens (4). The probe light input polarization-maintaining fiber (2) is arranged perpendicularly to the side wall (101) of the input end of the atomic gas chamber (1). The probe light output from the probe light input polarization-maintaining fiber (2) is incident on the atomic gas chamber (1) through the probe light input collimating superlens (4). The output end of the atomic gas cell (1) integrates a multi-wavelength composite superlens (5). The probe light output polarization-maintaining fiber (3) is arranged perpendicularly to the side wall (102) of the output end of the atomic gas cell (1) and is on the same straight line as the probe light input polarization-maintaining fiber (2). After the probe light is output from the atomic gas cell (1), it is coupled to the probe light output polarization-maintaining fiber (3) through the multi-wavelength composite superlens (5).

2. The fiber-optic integrated three-photon excited atomic gas cell probe based on an optical superlens according to claim 1, characterized in that, Both the probe light input collimating superlens (4) and the multi-wavelength composite superlens (5) are optical superlenses.

3. The fiber-optic integrated three-photon excited atomic gas cell probe based on an optical superlens according to claim 2, characterized in that, An optical superlens is fabricated on the input sidewall (101) of the atomic gas cell (1) using laser direct-writing optical superlens technology, forming a probe light input collimating superlens (4); and / or An optical superlens is fabricated on the output sidewall (102) of the atomic gas chamber (1) using laser direct writing optical superlens technology to form a multi-wavelength composite superlens (5).

4. The fiber-optic integrated three-photon excited atomic gas cell probe based on an optical superlens according to claim 2, characterized in that, An optical superlens is integrated onto the input sidewall (101) of the atomic gas cell (1) by optical adhesive bonding, thereby forming a probe light input collimating superlens (4); and / or The optical superlens is integrated onto the output sidewall (102) of the atomic gas cell (1) by optical adhesive bonding, thereby forming a multi-wavelength composite superlens (5).

5. The fiber-optic integrated three-photon excited atomic gas cell probe based on an optical superlens according to any one of claims 1 to 4, characterized in that, It also includes a polarization-maintaining fiber for adorned light input (6) and a polarization-maintaining fiber for coupled light input (7); The embellished light output from the polarization-maintaining fiber (6) is incident on the atomic gas cell (1) through the multi-wavelength composite superlens (5), and the coupled light output from the polarization-maintaining fiber (7) is incident on the atomic gas cell (1) through the multi-wavelength composite superlens (5).

6. The fiber-optic integrated three-photon excited atomic gas cell probe based on an optical superlens according to claim 5, characterized in that, The polarization-maintaining fiber (6) for the input of the decorative light is located directly below the polarization-maintaining fiber (3) for the output of the probe light; The input polarization-maintaining fiber (7) of the coupling light is located directly above the output polarization-maintaining fiber (3) of the probe light.

7. The fiber-optic integrated three-photon excited atomic gas cell probe based on an optical superlens according to claim 6, characterized in that, The probe light output from the probe light input polarization-maintaining fiber (2) is incident on the atomic gas cell (1) through the probe light input collimating superlens (4) to form the probe light collimated output beam (201). The embellishment light output from the embellishment light input polarization-maintaining fiber (6) is incident on the atomic gas cell (1) through the multi-wavelength composite superlens (5) to form the embellishment light collimated output beam (601). The coupling light output from the coupling light input polarization-maintaining fiber (7) is incident on the atomic gas cell (1) through the multi-wavelength composite superlens (5) to form the coupling light collimated output beam (701). The overlapping region (8) of the collimated output beam of the probe light (201), the collimated output beam of the embellishment light (601), and the collimated output beam of the coupling light (701) is the region where the Rydberg atom is located.

8. The fiber-optic integrated three-photon excited atomic gas cell probe based on an optical superlens according to any one of claims 1 to 4, characterized in that, The atomic gas chamber (1) uses a sealed shell that is filled with alkali metal atomic vapor.

9. The fiber-optic integrated three-photon excited atomic gas cell probe based on an optical superlens according to claim 8, characterized in that, The sealed shell is made of either all-glass or a mixture of silicon and glass.

10. The fiber-optic integrated three-photon excited atomic gas cell probe based on an optical superlens according to claim 8, characterized in that, Alkali metal atoms are either cesium or rubidium atoms.

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