Ultra-wideband large instantaneous bandwidth rydberg atom receiver based on field-enhanced waveguide chip and method thereof

Abstract

The application discloses a kind of based on field enhancement waveguide chip's ultra-wideband large instantaneous bandwidth Rydberg atom receiver and method thereof, comprising: probe light source and coupling light source, both reverse transmission through atomic vapor cell to eliminate Doppler broadening;Lens group, for the condensing of probe light and coupling light;Clock synchronization first radio frequency signal source and second radio frequency signal source, respectively generate local microwave signal and to be measured microwave signal;Power divider, for the two-way microwave signal combination;Field enhancement waveguide chip, atomic vapor cell is closely attached to its top, the microwave signal after combination is formed uniform microwave electric field in the center of atomic vapor cell by waveguide chip, realize atom superheterodyne down conversion and generate beat signal;Photodetector, receive and amplify the beat signal.The application can stably maintain large instantaneous bandwidth, with nanosecond pulse response capability, can be widely used in broadband electronic reconnaissance, millimeter wave radar, high-speed wireless communication and radio frequency metrology detection and other fields.

Description

Technical Field

[0001] This invention relates to the field of microwave electric field detection technology, and in particular to an ultrawideband large instantaneous bandwidth Rydberg atom receiver and its method based on a field-enhanced waveguide chip. Background Technology

[0002] With the rapid development of wireless communication, radar detection, spectrum monitoring, and high-precision electromagnetic metrology technologies, the demand for wide-band, high-sensitivity, and high-speed real-time measurement of microwave electric fields in complex electromagnetic environments continues to increase. Traditional microwave receiving equipment relies on discrete electronic components such as metal antennas, RF amplifiers, and bandpass filters. Constrained by the Chu limit, Johnson thermal noise, and the inherent operating range of the devices, a single set of equipment can only cover a limited octave band. Multi-band detection must rely on multiple RF channels or mechanical frequency modulation switching, resulting in a large overall size and low integration, making it difficult to adapt to the needs of miniaturized airborne and portable electromagnetic sensing equipment.

[0003] In recent years, microwave detection technology based on the electromagnetically induced transparency (EIT) effect of Rydberg atoms has become a research hotspot. Rydberg atoms possess core advantages such as ultra-large electric dipole moments, rich energy level structures, self-calibration, low field perturbation, and a detection bandwidth covering DC to terahertz, breaking through the inherent performance bottlenecks of traditional electronic antennas. However, existing Rydberg atom receiving schemes still suffer from two common technical pain points: First, it is impossible to simultaneously achieve supercontinuous operating bandwidth and stable instantaneous bandwidth. Most schemes only obtain large instantaneous bandwidth at a few discrete resonant frequencies, resulting in severe fluctuations in response across the entire frequency band. Second, the system hardware links are complex, the calibration process is cumbersome, and the engineering implementation is difficult. All existing schemes require the addition of a large number of auxiliary optical paths and external field control components, significantly increasing the overall size and power consumption, making it difficult to scale up for practical use.

[0004] The mainstream Rydberg atom receiving schemes currently include the following categories:

[0005] 1. Six-wave mixing scheme: This scheme achieves bandwidth enhancement through the rubidium atomic ladder energy level, but requires precise synchronization of the probe light, coupling light, local oscillator microwave, and signal microwave simultaneously. Frequency or power fluctuations in any of these channels will lead to a decrease in mixing efficiency, making it difficult to guarantee system stability. This scheme only achieves a large instantaneous bandwidth at the resonant frequency, while its bandwidth performance at non-resonant frequencies is poor.

[0006] 2. Stark frequency comb scheme: The bandwidth is improved by using a microwave frequency comb and a position-dependent gradient Stark field to form a Stark comb, but it requires multiple atomic gas cells and complex external electric field control, resulting in high system complexity. Moreover, it only obtains a large instantaneous bandwidth at the resonant frequency point.

[0007] 3. Magnetic Field Tuning Scheme: This scheme relies on the Zeeman effect of a static magnetic field to continuously tune the Rydberg levels, achieving continuous high-sensitivity microwave detection from 1-40 GHz. However, it requires changing multiple sets of Rydberg operating levels corresponding to different principal quantum numbers, resulting in a time-consuming switching process and making it difficult to achieve real-time, rapid cross-frequency signal reception. The system includes multiple independent optical path modules, and the accompanying permanent magnets are prone to magnetic field crosstalk, requiring multiple layers of magnetic shielding, significantly increasing the size and weight of the equipment.

[0008] 4. Space division multiplexing RF chip solution: Parallel reception of arbitrary dual-frequency microwave signals in a wide frequency band is achieved through two sets of independent integrated RF chips - rubidium gas chamber detection modules. However, the instantaneous bandwidth of the system is only 100kHz, which makes it difficult to handle large-bandwidth instantaneous frequency hopping signals and limits the ability to synchronously detect dense multi-frequency signals.

[0009] The aforementioned solutions collectively reveal two core flaws: poor consistency of instantaneous bandwidth across the entire frequency band and complex overall hardware with low feasibility for engineering implementation. Six-wave mixing and Stark optical frequency combs both involve complex hardware links such as multi-path optical / microwave synchronization, multi-chamber arrays, and external field control; the magnetic field tuning solution requires permanent magnets and multi-layer magnetic shielding, making frequency band switching calibration procedures cumbersome; the space division multiplexing architecture presents high difficulty in consistent debugging of dual optical path channels and suffers from signal crosstalk between channels. All four solutions struggle to maintain a stable 10 MHz-level uniform instantaneous bandwidth across an ultra-wide continuous frequency band spanning nine octaves from 0.08 to 41 GHz. Some solutions also require additional components such as high-stability cavity frequency locking and multiple auxiliary RF channels. Furthermore, none of them have systematically optimized engineering details such as laser spot matching, differential noise reduction, and nanosecond-level pulse transient response, making them unsuitable for multiple application scenarios such as broadband wireless communication, pulse radar, and broadband electromagnetic reconnaissance.

[0010] Therefore, there is an urgent need for a new type of Rydberg atomic receiver that can achieve stable large instantaneous bandwidth in an ultra-wide continuous frequency band, and has a simple hardware structure and is easy to engineer. Summary of the Invention

[0011] This invention addresses the shortcomings of existing technologies by providing an ultrawideband large instantaneous bandwidth Rydberg atom receiver and its method based on a field-enhanced waveguide chip.

[0012] To achieve the above-mentioned objectives, the technical solution adopted by the present invention is as follows:

[0013] An ultrawidebandwidth Rydberg atom receiver based on a field-enhanced waveguide chip, characterized in that it comprises:

[0014] A probe light source is used to generate probe light, which drives ground-state atoms to transition to excited states;

[0015] A coupled light source is used to generate coupled light, which drives the excited state to transition to the Rydberg state;

[0016] An atomic vapor chamber through which the probe light and coupling light are transmitted in opposite directions to eliminate Doppler broadening;

[0017] The lens group is used to reduce the laser beam waist radius and form a long coherence length at the center of the atomic vapor chamber by respectively reducing the probe beam and coupling beam.

[0018] The first and second radio frequency signal sources, which are clock-synchronized, are used to generate the local oscillator microwave signal and the microwave signal under test, respectively.

[0019] A power divider is used to combine the local oscillator microwave signal and the microwave signal under test.

[0020] The field-enhanced waveguide chip has an atomic vapor chamber that is closely attached to the top of it. The output of the power divider is connected to the input of the field-enhanced waveguide chip. The combined microwave signal forms a uniform microwave electric field at the center of the atomic vapor chamber through the field-enhanced waveguide chip, which couples Rydberg atoms and realizes atomic superheterodyne downconversion to generate a beat frequency signal.

[0021] A photodetector is used to receive and amplify the beat frequency signal.

[0022] Furthermore, the wavelength of the probe light is 455.656 nm, used to drive cesium atoms from the ground state 6S. 1 / 2 Energy level transition to excited state 7P 3 / 2 Energy level; the wavelength of the coupled light is 1066.342 nm, used to drive cesium atoms from the excited state 7P. 3 / 2 The energy level transitions to the Ridburg state 39D5 / 2.

[0023] Furthermore, the lenses in the lens group are plano-convex lenses with a focal length of 400-600mm.

[0024] Furthermore, the receiver also includes a heating element and a balanced differential detector; the heating element is alternately arranged in opposite directions to heat the atomic vapor chamber and reduce noise; after the probe light is split, the balanced differential detector is used to eliminate common-mode noise.

[0025] Furthermore, the field-enhancing waveguide chip has a periodic microstructure for achieving localized enhancement of the microwave electric field in the atomic interaction region of the atomic vapor chamber.

[0026] Furthermore, the first radio frequency signal source and / or the second radio frequency signal source are used to output signals arbitrarily within the frequency range of 0.07 GHz to 43 GHz, and the difference between the frequency of the microwave signal under test and the frequency of the local oscillator signal is _____. , Scan from 500kHz to 20MHz.

[0027] This invention also discloses an ultra-wideband, large instantaneous bandwidth Rydberg atom receiving method based on a field-enhanced waveguide chip, applied to the aforementioned receiver, comprising the following steps:

[0028] The probe light and coupling light are reverse-transmitted through the atomic vapor chamber to eliminate Doppler broadening;

[0029] The probe light and coupling light are compressed using a lens group to reduce the laser beam waist radius and form a long coherence length at the center of the atomic vapor chamber;

[0030] The local oscillator microwave signal and the microwave signal under test are generated by the first and second radio frequency signal sources synchronized by clock, respectively. The two are combined by a power divider and then input into the field enhancement waveguide chip to form a uniform microwave electric field at the center of the cesium atom vapor chamber, so as to couple the Rydberg atom and realize the superheterodyne downconversion of the atom to generate the beat frequency signal.

[0031] The beat frequency signal is received and amplified by a photodetector.

[0032] Furthermore, the ultra-wideband large instantaneous bandwidth Rydberg atomic receiver method also includes: acquiring the spectrum signal through a spectrum analyzer and optimizing the laser parameters to obtain the maximum instantaneous bandwidth of the receiver at each local oscillator frequency.

[0033] Furthermore, the ultra-wideband large instantaneous bandwidth Rydberg atom receiving method further includes: an FM modulation signal output from a radio frequency source is input into a waveguide chip along with a local oscillator signal, coupled with a Rydberg atom, a probe light is received by a photodetector, and a spectrum analyzer is used to acquire the spectrum signal to completely distinguish the upper and lower sideband spectra of the frequency modulation.

[0034] Furthermore, the ultra-wideband large instantaneous bandwidth Rydberg atom receiving method further includes: a radio frequency source outputting a narrow microwave pulse of 20ns to 90ns, which is not mixed with the local oscillator field, and is directly coupled to the Rydberg atom through a waveguide chip, the probe light is received by a photodetector, and the time domain signal is obtained by an oscilloscope, so as to reproduce the complete envelope of the narrow pulse without distortion.

[0035] Compared with the prior art, the advantages of the present invention are as follows:

[0036] I. Ultra-wide continuous operating frequency band, with uniform and stable instantaneous bandwidth across the entire frequency band.

[0037] This invention achieves microwave signal reception across an ultra-wide continuous frequency band spanning nine octaves, from 0.08 GHz to 41 GHz, through the synergistic optimization of a low-loss field-enhanced waveguide chip and two-photon Rabi parameters. The system maintains a stable -3dB instantaneous bandwidth above 10.2 MHz across the entire frequency band, reaching 19.5 MHz at 0.08 GHz and maintaining 12.5 MHz at 41 GHz. The response curves at different frequencies exhibit highly consistent characteristics, overcoming the drawback of traditional Rydberg receivers where bandwidth drops sharply at high frequencies. Compared to existing six-wave mixing, Stark optical frequency comb, and magnetic field tuning schemes, this invention eliminates the need for frequent Rydberg level replacements and external control fields. A single measurement can simultaneously acquire multiple signals, including wideband frequency hopping and radar pulses, avoiding the problem of losing target signals due to segmented spectrum scanning.

[0038] II. The overall structure is simple, and its engineering feasibility is strong.

[0039] This invention employs only two laser paths and one combined microwave link, eliminating the need for complex components such as the four-path optoelectronic synchronization module required by the six-wave mixing scheme, the multiple gas cell arrays and external electric field control components of the Stark scheme, the permanent magnets and multi-layer magnetic shielding devices of the magnetic field tuning scheme, and the laser resonant frequency locking. Furthermore, it uses a field-enhancing waveguide chip instead of the traditional free-space horn antenna radiation scheme, simplifying the optical path and RF wiring and significantly reducing debugging steps. The device is small in size, has low hardware cost, and low power consumption, making it suitable for manufacturing small portable devices and possessing excellent prospects for engineering and commercialization.

[0040] III. High microwave-atomic coupling efficiency significantly enhances the ability to detect weak signals.

[0041] By employing a long-focal-length plano-convex lens (e.g., 500mm focal length) to compress the laser spot, the coherent interaction distance between the laser and atoms is extended. Heating the atomic gas chamber to 60°C increases the atomic number density, enhancing the coupling strength between atoms and the laser and microwave fields. The heating element uses an alternating forward and reverse winding layout to suppress stray electromagnetic fields generated during heating. Periodic microstructures on the waveguide chip can locally enhance the microwave electric field in the atomic interaction region of the gas chamber, avoiding signal attenuation caused by beam divergence and high transmission loss in traditional horn radiation. These measures result in a more significant atomic level response, with superior detection sensitivity for weak microwave signals compared to traditional antenna radiation schemes. Furthermore, the use of a balanced differential detector to eliminate common-mode noise further improves the signal-to-noise ratio of the intermediate frequency signal. Attached Figure Description

[0042] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 These are the cesium atom two-photon EIT energy level structure diagram and the measured transmission spectrum of an embodiment of the present invention. Among them, (a) is the cesium atom two-photon EIT energy level structure diagram; (b) is the measured EIT transmission spectrum.

[0044] Figure 2 This is a schematic diagram of the experimental apparatus according to an embodiment of the present invention.

[0045] Figure 3 The figures shown are the instantaneous bandwidth calibration test results of the system according to an embodiment of the present invention. Among them, (a) is a cloud map showing the change of instantaneous bandwidth with the coupling light Rabi frequency; (b) is a cloud map showing the change of instantaneous bandwidth with the probe light Rabi frequency; (c) is a full-band instantaneous bandwidth distribution map; (d) is a system frequency response curve at different coupling light Rabi frequencies; (e) is a system frequency response curve at different probe light Rabi frequencies; and (f) is a system frequency response curve corresponding to multiple typical frequency points.

[0046] Figure 4 This is a spectrum diagram of FM signal reception at multiple frequency points during instantaneous bandwidth frequency domain testing of an atomic system according to an embodiment of the present invention.

[0047] Figure 5 This is a time-domain test result diagram of the instantaneous bandwidth of the atomic system according to an embodiment of the present invention. Among them, (a) is the original radio frequency pulse waveform output by the signal source; (b) is the pulse time-domain response waveform detected by the atomic receiver.

[0048] Figure 6 The figures shown are experimental results of BPSK image transmission according to an embodiment of the present invention. Among them, (a) is a block diagram of the entire image transmission and reception link; (b) is the system frequency response characteristic curve; (c) is the reconstructed image corresponding to different symbol rates; and (d) is a comparison curve of the bit error rate and packet loss rate as a function of symbol rate. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] This invention provides an ultrawideband large instantaneous bandwidth Rydberg atom receiver based on a field-enhanced waveguide chip. Its core components include: a two-photon laser excitation optical path module, a temperature-controlled cesium atom gas cell module, an integrated microwave waveguide chip module, a microwave signal combining and feeding module, a differential photoelectric detection readout module, and a software-defined radio digital demodulation processing module.

[0051] The present invention uses probe light and coupling light to propagate in opposite directions through an atomic vapor chamber to eliminate Doppler broadening, wherein the probe light drives ground-state atoms to transition to excited states, and the coupling light drives excited states to transition to Rydberg states;

[0052] The probe light and coupling light are compressed using a lens to reduce the laser beam waist radius and form a long coherence length at the center of the atomic vapor chamber;

[0053] The local oscillator microwave signal and the microwave signal under test are generated by a clock-synchronized radio frequency signal source. The two are combined by a power divider and then input into the waveguide chip to form a uniform microwave electric field at the center of the cesium atom vapor chamber, so as to couple the Rydberg atom and realize the superheterodyne downconversion of the atom to generate a beat frequency signal.

[0054] The radio frequency signal source outputs a local oscillator signal arbitrarily within the frequency range of 0.07 GHz to 43 GHz. The frequency difference between the microwave signal under test and the local oscillator signal is [value missing]. The signal is scanned from 500kHz to 20MHz. The beat frequency signal is received and amplified by a photodetector. The spectrum signal is then obtained by a spectrum analyzer to optimize the laser parameters, thereby obtaining the maximum instantaneous bandwidth of the receiver at each local oscillator frequency.

[0055] The radio frequency source outputs an FM modulated signal at any typical operating frequency point from 0.1 GHz to 40 GHz, which is input into the waveguide chip along with the local oscillator signal. The signal is coupled with the Rydberg atom and the probe light is received by a photodetector. The spectrum signal is then obtained by a spectrum analyzer to completely distinguish the upper and lower sideband spectra of the FM signal and verify the system's large signal bandwidth receiving capability.

[0056] The radio frequency source outputs a narrow microwave pulse of 20ns to 90ns, which is not mixed with the local oscillator field. It is directly coupled to the Rydberg atom through the waveguide chip, and the probe light is received by the photodetector. The time domain signal is then acquired by the oscilloscope. The complete envelope of the 20ns ultra-narrow pulse can be reproduced without distortion, verifying that the system has the ability to capture nanosecond-level transient electromagnetic pulses.

[0057] The RF source outputs an RF signal encoding a color image, which, along with the local oscillator signal, is input to a waveguide chip. There, it couples with a Rydberg atom, receives the probe light through a photodetector, and then uses software-defined radio equipment to decode and reconstruct the original image. At different symbol rates, the bit error rate (BER) and packet loss rate (PMR) exhibit certain trends, verifying the system's ability to receive high-speed signals.

[0058] Combined with appendix Figure 1 In the cesium atom three-level system shown in (a), this invention uses a 455nm probe laser and a 1066nm coupling laser to construct a trapezoidal two-photon electromagnetically induced transparent (EIT) coherent excitation optical path, and the 455nm probe laser locks onto the cesium atom. Ground state to intermediate state transition, 1066nm coupled laser resonant drive atomic excitation to Target Ryd state; when a microwave electric field is applied to a Ryd atom, the alternating Stark effect induces a time-varying shift in the Ryd energy level. This energy level shift directly alters the transmission intensity of the two-photon electromagnetically induced transparency (EIT) window, thereby enabling optical readout of microwave electric field information. (Appendix) Figure 1 (b) is the two-photon EIT transmission spectrum obtained by actual measurement in this invention. The horizontal axis is the detuning of the coupled laser, and the vertical axis is the transmission intensity of the probe light.

[0059] Experimental setup such as Figure 2 As shown, it mainly consists of six core parts: a detection optical path module, a reference optical path module, an atomic gas cell module, an integrated microwave waveguide chip module, a microwave signal combining and feeding module, and a differential photoelectric detection readout module.

[0060] Optical path system: The optical path part of the experimental setup, such as... Figure 2 As shown. The probe light (wavelength 1066nm) is generated by a probe light source, introduced into the left side of the device through an optical fiber, collimated and expanded by a lens, and then its polarization state is adjusted by a half-wave plate (HWP). Subsequently, it is reflected by a dichroic mirror (DM) and passes vertically downward through the atomic gas cell (RPD). The transmitted probe light is received by a photodetector (PD) in the upper left corner, and the output electrical signal is labeled "signal".

[0061] The coupled light (wavelength 455nm) is generated by a coupled light source, introduced into the right side of the device through an optical fiber, collimated and expanded by a lens, and its polarization state is adjusted by a half-wave plate (HWP). After passing through a dichroic mirror (DM), it is transmitted directly through the atomic gas cell (RPD) and exits. The two beams propagate in opposite directions and overlap within the atomic gas cell, forming a two-photon electromagnetically induced transparent (EIT) coherent excitation system.

[0062] Microwave Feed System: The microwave signal under test (SIG) and the local oscillator (LO) are generated separately by two vector RF signal sources and connected to the input of the power divider via coaxial cables. The power divider combines the two microwave signals and feeds them into the input port of the integrated microwave waveguide chip module at the bottom. The atomic gas cell (RPD) is tightly attached to the top of the waveguide chip. The chip has periodic microstructures that can form a uniform and strongly confined microwave electric field in the atomic interaction region of the gas cell.

[0063] The probe laser is first split into two parallel beams—a probe branch and a reference branch—by a window. The polarization of the two beams is uniformly adjusted by a half-wave plate (HWP) to ensure polarization matching with the microwave electric field. The coupling laser propagates in the opposite direction to the probe beam. Both beams are focused by a 500mm focal length lens onto the overlapping region at the center of the atomic gas cell (RPD). The coupling beam 1 / e 2 Spot radius 273 Detection beam 1 / e 2 Spot radius 238 The beam size has been optimized to balance atomic interaction length and instantaneous bandwidth performance. The system incorporates a 5cm cylindrical sealed cesium atom gas chamber, with a temperature control device maintaining a constant temperature of 60°C. This increases the cesium atom number density within the chamber, effectively enhancing the EIT transmission signal amplitude and reducing the system noise floor. The probe beam, after passing through the atom gas chamber, is input together with the reference beam into a 45MHz bandwidth balanced photodetector (PD). Differential readout is used to cancel the laser's own amplitude noise, significantly improving the intermediate frequency signal-to-noise ratio.

[0064] The microwave feed section employs a low-loss field-enhanced waveguide chip architecture, abandoning the traditional free-space horn antenna radiation scheme. The microwave signal under test (SIG) and the local oscillator (LO) are generated separately by a vector RF signal source. After being combined by a resistive power divider, the two microwave signals are directly fed to the waveguide chip input port via a coaxial cable, as shown in the attached diagram. Figure 2 As shown, the cesium gas cell is tightly attached to the top of the waveguide chip. The chip's periodic microstructure can achieve localized enhancement of the microwave electric field in the atomic interaction region of the gas cell, ensuring uniform microwave action on the Reid atoms across the entire frequency band from 0.07 GHz to 43 GHz, eliminating spatial loss and beam divergence problems caused by free-space radiation. The strong local oscillator electric field and the weak electric field of the signal under test act together on... Reed levels, which rely on the alternating Stark effect to produce time-varying level shifts. Then, the EIT transmittance is periodically modulated, and the frequency difference, phase difference, and amplitude information of the two microwaves are all converted into the intermediate frequency beat frequency electrical signal output by the photodetector, thus completing the signal conversion from microwave to light and then to electricity.

[0065] Appendix Figure 3 This is the complete set of calibration test results for the instantaneous bandwidth of the system of this invention, wherein... Figure 3(a) Figure 3 (d) Used to characterize the Rabi frequency of the coupled laser The regulation law of the system's instantaneous bandwidth is shown in the thermogram, which represents the normalized atomic response intensity, with the white solid line representing the system's -3dB bandwidth boundary. As the coupled light Rabi frequency gradually increases from 1.44MHz to 16.2MHz, the system's instantaneous bandwidth rapidly increases and tends to saturate. Above 2.638MHz, the bandwidth no longer increases significantly, but only fluctuates slightly, indicating that a stable atomic coherence can be established with sufficient coupled optical field, and further increasing the coupling power has limited effect on bandwidth gain. Figure 3 (b) Figure 3 (e) Characterizing the Rabi frequency of the probe laser Due to the influence of [the specific effect], the bandwidth exhibits a non-monotonic change with the probe optical power. At 24.1 MHz, the system reaches a peak instantaneous bandwidth of 13 MHz. If the probe power is further increased, decoherence mechanisms such as optical pumping, power broadening, and Ryd state loss will be aggravated, resulting in atomic coherence attenuation and demodulation bandwidth reduction. Figure 3 (c) Figure 3 (f) For the full-band bandwidth uniformity test, typical local oscillator frequencies of 0.08 GHz, 12 GHz, 25 GHz, and 41 GHz were selected for testing. The system's -3 dB instantaneous bandwidth remained stable above 10.2 MHz across the entire frequency band. The bandwidth at the low frequency of 0.08 GHz reached 19.5 MHz, and the high frequency of 41 GHz still maintained 12.5 MHz. The response curves at different frequency points were highly consistent, proving that the present invention can achieve microwave reception with uniform bandwidth and no significant performance degradation in the ultra-wide range of 0.08–41 GHz, overcoming the defect of the cliff-like drop in high-frequency bandwidth of traditional Reed receivers.

[0066] Appendix Figure 4 The measured spectrum of full-band FM signal reception covers all typical operating frequencies from 1 GHz to 40 GHz. Each sub-graph corresponds to the demodulated output spectrum under a single local oscillator carrier frequency. The test used a standard FM signal with a maximum frequency deviation of 10 MHz and a modulation rate of 0.1 MHz, and the resolution bandwidth of the spectrum analyzer was set to 100 Hz. The upper and lower sideband spectral structures of the FM signal can be completely distinguished at all frequencies. In other mid-to-high frequency scenarios, even with the introduction of small insertion losses due to RF cables and waveguides, the modulation sideband outlines remain clear and complete, without sideband loss or spectral distortion. This fully verifies that the present invention has the ability to stably demodulate FM communication signals in an ultra-wide frequency domain, making it suitable for broadband FM radar and FM wireless communication equipment detection scenarios.

[0067] Appendix Figure 5 The time-domain response spectrum of a narrow microwave pulse is shown. Figure 5(a) is the original output pulse waveform of the radio frequency signal source, with the pulse width gradient set from 20ns to 90ns and the pulse falling edge of the signal source being only 4.35ns; Figure 5 (b) is the time-domain detection waveform output by the atomic receiver of the present invention. The measured signal rise time of the system is 12.12ns. It can reproduce the complete envelope of the 20ns extremely narrow pulse without distortion. There are no problems such as signal tailing, amplitude distortion, or leading edge distortion. This proves that the present invention has nanosecond-level time resolution capability and can capture instantaneous short electromagnetic pulse signals. It is suitable for application scenarios such as pulse radar and electromagnetic transient interference detection.

[0068] Appendix Figure 6 This invention provides a complete verification system and test data for high-speed BPSK wireless image transmission. (Attached) Figure 6 (a) A complete flowchart illustrating the entire link process of signal encoding, modulation, atomic reception, and software radio demodulation: the original color image is converted into a binary bitstream and a synchronization preamble is added; BPSK modulation is applied to the 10.01GHz carrier; the local oscillator microwave is set to 10GHz; the two generate a 10MHz intermediate frequency, which is then sent to the software radio SDR to complete digital down-conversion, symbol synchronization, and image reconstruction. (Appendix) Figure 6 (b) shows the system's mid-frequency response curve under a 10GHz local oscillator, with a 3dB bandwidth covering approximately 9MHz, meeting the requirements for high-speed digital signal demodulation. (See attached image) Figure 6 (c) Images reconstructed at multi-symbol rates from 200 ksps to 10 Msps are displayed. Images at rates of 6 Msps and below are complete and clear; above 6 Msps, demodulation performance gradually deteriorates due to system signal-to-noise ratio constraints, resulting in image distortion. (Appendix) Figure 6 (d) Quantitatively analyze the bit error rate (BER) and packet loss rate (PMR) at different symbol rates. Within 6 Msps, both BER and PMR are 0, which can achieve lossless image transmission with zero bit error and zero packet loss. As the symbol rate continues to increase, the system signal-to-noise ratio is insufficient, and bit error and packet loss increase simultaneously. Quantitatively define the upper limit of the digital communication carrying performance of this invention.

[0069] The entire solution requires no additional complex auxiliary hardware such as magnetic field control, optical frequency comb generation, or optical frequency stabilization resonator. It can achieve three core performance characteristics simultaneously by relying solely on low-loss field-enhanced waveguide chips and two-photon EIT optical path parameter optimization: a nine-fold frequency multiplication super-continuous operating frequency band of 0.08–41 GHz, a stable instantaneous demodulation bandwidth of ≥10.2 MHz across the entire frequency band, and an ultra-fast time-domain response of 12.12 ns. It can be widely used in broadband electronic reconnaissance, millimeter-wave radar, high-speed wireless communication, radio frequency metrology and testing, and other scenarios.

[0070] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A super-widebandwidth Rydberg atom receiver based on a field-enhanced waveguide chip, characterized in that, include: A probe light source is used to generate probe light, which drives ground-state atoms to transition to excited states; A coupled light source is used to generate coupled light, which drives the excited state to transition to the Rydberg state; An atomic vapor chamber through which the probe light and coupling light are transmitted in opposite directions to eliminate Doppler broadening; The lens group is used to reduce the laser beam waist radius and form a long coherence length at the center of the atomic vapor chamber by respectively reducing the probe beam and coupling beam. The first and second radio frequency signal sources, which are clock-synchronized, are used to generate the local oscillator microwave signal and the microwave signal under test, respectively. A power divider is used to combine the local oscillator microwave signal and the microwave signal under test. The field-enhanced waveguide chip has an atomic vapor chamber that is closely attached to the top of it. The output of the power divider is connected to the input of the field-enhanced waveguide chip. The combined microwave signal forms a uniform microwave electric field at the center of the atomic vapor chamber through the field-enhanced waveguide chip, which couples Rydberg atoms and realizes atomic superheterodyne downconversion to generate a beat frequency signal. A photodetector is used to receive and amplify the beat frequency signal.

2. The receiver according to claim 1, characterized in that, The probe light has a wavelength of 455.656 nm and is used to drive cesium atoms from their ground state 6S. 1 / 2 Energy level transition to excited state 7P 3 / 2 Energy level; the wavelength of the coupled light is 1066.342 nm, used to drive cesium atoms from the excited state 7P. 3 / 2 Energy level transition to the Ridburg state 39D 5 / 2 energy level.

3. The receiver according to claim 1, characterized in that, The lenses in the lens group are plano-convex lenses with a focal length of 400-600mm.

4. The receiver according to claim 1, characterized in that, It also includes a heating element and a balanced differential detector; the heating element is arranged alternately in opposite directions to heat the atomic vapor chamber and reduce noise; after the probe light is split, the balanced differential detector is used to eliminate common-mode noise.

5. The receiver according to claim 1, characterized in that, The field-enhancing waveguide chip has a periodic microstructure for achieving localized enhancement of the microwave electric field in the atomic interaction region of the atomic vapor chamber.

6. The receiver according to claim 1, characterized in that, The first radio frequency signal source and / or the second radio frequency signal source are used to output signals arbitrarily within the frequency range of 0.07 GHz to 43 GHz, and the difference between the frequency of the microwave signal under test and the frequency of the local oscillator signal is _____. , Scan from 500kHz to 20MHz.

7. A method for ultra-widebandwidth Rydberg atomic reception based on a field-enhanced waveguide chip, applied to the receiver according to any one of claims 1 to 6, characterized in that, Includes the following steps: The probe light and coupling light are reverse-transmitted through the atomic vapor chamber to eliminate Doppler broadening; The probe light and coupling light are compressed using a lens group to reduce the laser beam waist radius and form a long coherence length at the center of the atomic vapor chamber; The local oscillator microwave signal and the microwave signal under test are generated by the first and second radio frequency signal sources synchronized by clock, respectively. The two are combined by a power divider and then input into the field enhancement waveguide chip to form a uniform microwave electric field at the center of the cesium atom vapor chamber, so as to couple the Rydberg atom and realize the superheterodyne downconversion of the atom to generate the beat frequency signal. The beat frequency signal is received and amplified by a photodetector.

8. The method according to claim 7, characterized in that, Also includes: The maximum instantaneous bandwidth of the receiver at each local oscillator frequency is obtained by acquiring the spectrum signal through a spectrum analyzer and optimizing the laser parameters.

9. The method according to claim 7, characterized in that, Also includes: The FM modulation signal output by the radio frequency source is input into the waveguide chip along with the local oscillator signal. It is coupled with the Rydberg atom and the probe light is received by the photodetector. The spectrum signal is then obtained by the spectrum analyzer to completely distinguish the upper and lower sideband spectra of the frequency modulation.

10. The method according to claim 7, characterized in that, Also includes: The radio frequency source outputs narrow microwave pulses from 20ns to 90ns, which are not mixed with the local oscillator field. They are directly coupled to Rydberg atoms through a waveguide chip, and the probe light is received by a photodetector. The time domain signal is then acquired using an oscilloscope, and the complete envelope of the narrow pulse is reproduced without distortion.

Images