Optical microcavity coupling structure based on photonic line bonding waveguide and packaging method thereof

Abstract

The invention discloses an optical microcavity coupling structure based on a photonic line bonding waveguide and a packaging method thereof. The optical microcavity coupling structure comprises a shell, an optical fiber array and an optical microcavity; the shell comprises a base and a top cover, the base is provided with a supporting table, and the optical microcavity is fixed on the surface of the supporting table; the optical fiber array comprises a photonic line bonding waveguide, a first end of the optical fiber array is fixed on the surface of the supporting table, and a bending area of the photonic line bonding waveguide is coupled with the optical microcavity; the first end of the optical fiber array, the photonic line bonding waveguide and the optical microcavity are packaged in the shell, and the second end of the optical fiber array extends to the outside of the shell. According to the optical microcavity coupling structure provided by the invention, efficient evanescent coupling of the PWB and the optical microcavity is realized, the photonic line bonding waveguide and the optical microcavity are packaged in the shell, the coupling precision is high, the reliability is high, the external interference resistance is high, and a solution is provided for large-scale integration of the on-chip optical microcavity and an integrated photonics system.

Description

Technical Field

[0001] The present invention relates to the technical field of optical devices, and in particular to an optical microcavity coupling structure based on photon circuit bonding waveguide and a packaging method thereof. Background Art

[0002] Optical microcavities with extremely high Q values ​​(quality factors) provide an attractive research platform for a variety of cutting-edge photonic applications due to their excellent light field localization capabilities and ultra-low loss characteristics. In the field of nonlinear optics, such optical microcavities can efficiently generate broadband optical frequency combs through the Kerr effect, and their compact size and low power consumption characteristics have opened up new ways to realize chip-level optical frequency combs. In terms of high-precision metrology, the enhanced interaction length of optical microcavities significantly improves the sensing sensitivity, making them unique in applications such as trace gas detection and nanoparticle sensing. In telecommunications systems, high-Q optical microcavities can achieve low-threshold optical parametric oscillations, providing a new light source solution for wavelength division multiplexing technology. In the field of microwave photonics, optical microcavities based on two-color pumping can generate microwave signals with low phase noise, and their spectral purity is better than that of traditional electronic methods. In addition, by introducing active frequency stabilization technology, such microcavities can produce laser output with sub-hertz linewidth, providing an ideal light source for applications such as atomic clocks and coherent communications. It is particularly noteworthy that the combination of optical microcavities and atomic transition spectra can construct optical frequency references with long-term stability, laying the foundation for the miniaturization of the next generation of time and frequency standard systems. The realization of these diverse applications is mainly due to the unique physical properties of optical microcavities in terms of enhanced light-matter interaction, mode volume compression, and regulation of nonlinear effects.

[0003] In addition, as photonic devices develop towards miniaturization and low power consumption, the demand for compactness and nonlinear optical effects with low power thresholds is becoming increasingly urgent, which further promotes the research on integrated and scalable solutions. However, these high-performance optical microcavities face a key challenge in practical applications: the need to find a stable, compact and efficient coupling solution to replace traditional free-space coupling devices (such as tapered fibers, prisms and end-face coupling). Although these traditional coupling methods are widely used, they have obvious limitations - tapered fibers have low mechanical strength and are easily affected by environmental vibrations; prism coupling systems are bulky and difficult to integrate; end-face coupling alignment accuracy requirements are stringent and long-term stability is insufficient. Summary of the invention

[0004] The embodiment of the present invention provides an optical microcavity coupling structure based on a photonic wire bonding waveguide and a packaging method thereof. The optical microcavity coupling structure realizes efficient evanescent coupling between photonic wire bonding (PWB) and an optical microcavity, and encapsulates the photonic wire bonding waveguide and the optical microcavity in a shell, has high coupling accuracy, high reliability, and strong resistance to external interference, and provides a solution for the large-scale integration of on-chip optical microcavities and integrated photonics systems.

[0005] According to one aspect of the present invention, there is provided an optical microcavity coupling structure based on photon circuit bonding waveguide, comprising a housing, an optical fiber array and an optical microcavity;

[0006] The housing comprises a base and a top cover, the base is provided with a support platform, and the optical microcavity is fixed on the surface of the support platform;

[0007] The first end of the optical fiber array comprises a photon circuit bonding waveguide in a curved shape, the two ends of the photon circuit bonding waveguide are respectively connected to two optical fibers of the optical fiber array, the first end of the optical fiber array is fixed to the surface of the support platform, the curved region of the photon circuit bonding waveguide is coupled to the optical microcavity, and the photon circuit bonding waveguide is suspended;

[0008] The first end of the optical fiber array, the photonic circuit bonding waveguide and the optical microcavity are packaged inside the housing formed by the base and the top cover, and the second end of the optical fiber array extends to the outside of the housing.

[0009] Optionally, the photonic circuit bonding waveguide is in a U-shape.

[0010] Optionally, the bending diameter of the photonic circuit bonding waveguide is 127 μm, the waveguide diameter is 2 μm, and the insertion loss is less than or equal to 2.5 dB.

[0011] Optionally, the shape of the photonic circuit bonding waveguide includes a spiral shape.

[0012] Optionally, the photonic circuit bonding waveguide is formed by using negative photoresist through femtosecond laser direct writing technology or two-photon polymerization direct writing technology.

[0013] Optionally, the negative photoresist is doped with germanium dioxide.

[0014] Optionally, the optical microcavity is fixed to the surface of the support platform by means of a heat-conductive double-sided adhesive, and the optical fiber array includes a glass shell, and the glass shell is fixed to the surface of the support platform by means of a UV-curing adhesive.

[0015] Optionally, the optical microcavity comprises an on-chip integrated silicon oxide microring core cavity, the core layer thickness of the silicon oxide microring core cavity is 8 μm, and the ring diameter is 1630 μm.

[0016] According to another aspect of the present invention, a packaging method of an optical microcavity coupling structure based on a photonic circuit bonding waveguide is provided, which is used to package the above optical microcavity coupling structure, and the packaging method comprises:

[0017] A housing, an optical fiber array and an optical microcavity are provided, wherein the housing comprises a base and a top cover, the base is provided with a support platform, and the first end of the optical fiber array comprises a photonic circuit bonding waveguide with a bent shape;

[0018] Fixing the optical microcavity on the surface of the support platform;

[0019] Placing the first end of the optical fiber array on the surface of the support platform, adjusting the coupling between the photonic circuit bonding waveguide and the optical microcavity, and then fixing the first end of the optical fiber array on the surface of the support platform;

[0020] The first end of the optical fiber array, the photon circuit bonding waveguide and the optical microcavity are encapsulated inside the housing formed by the base and the top cover, and the second end of the optical fiber array extends to the outside of the housing.

[0021] Optionally, placing the first end of the optical fiber array on the surface of the support platform, adjusting the coupling between the photonic circuit bonding waveguide and the optical microcavity, and then fixing the first end of the optical fiber array on the surface of the support platform comprises:

[0022] Clamp the optical fiber array with a fixture and place it on the surface of the support platform;

[0023] Using a three-dimensional translation stage and a piezoelectric displacement stage to control the movement of the base so that the optical microcavity is coupled with the curved region of the photonic circuit bonding waveguide;

[0024] monitoring the coupling state of the optical microcavity and the photonic circuit bonding waveguide, and when a target coupling state is reached, fixing the first end of the optical fiber array to the surface of the support platform;

[0025] Wherein, the photonic circuit bonding waveguide is suspended.

[0026] The optical microcavity coupling structure based on photon circuit bonding waveguide provided by the embodiment of the present invention comprises a housing, an optical fiber array and an optical microcavity; the housing comprises a base and a top cover, the base is provided with a support platform, the first end of the optical fiber array comprises a curved photon circuit bonding waveguide, the two ends of the photon circuit bonding waveguide are respectively connected to two optical fibers of the optical fiber array, the optical microcavity and the first end of the optical fiber array are fixed to the surface of the support platform, so that the curved area of ​​the photon circuit bonding waveguide is coupled with the optical microcavity, and the photon circuit bonding waveguide is suspended; the first end of the optical fiber array, the photon circuit bonding waveguide and the optical microcavity are encapsulated in the housing formed by the base and the top cover, and the second end of the optical fiber array extends to the outside of the housing, so that the anti-interference of the coupling between the optical microcavity and the photon circuit bonding waveguide is enhanced, and the coupling efficiency and the stability of the quality factor of the optical microcavity are ensured. The technical solution of the embodiment of the present invention realizes the efficient evanescent coupling between the PWB and the optical microcavity, and provides a solution for the large-scale integration of on-chip optical microcavity and integrated photonics system. The experimental results show that the coupling structure provided by the embodiment of the present invention achieves a coupling efficiency of more than 90% in the 1550nm band, while maintaining the intrinsic Q value of the optical microcavity>10 7 . PWB technology can flexibly construct low-loss (<2.5dB) optical interconnect structures in three-dimensional space through additive manufacturing processes such as femtosecond laser direct writing or two-photon polymerization. Its core advantages are: low manufacturing cost: no complex alignment process is required, and single-step molding solves the problem of sub-micron precision positioning required for traditional split optical fibers; small size: the cross-sectional size can be compressed to 1×2μm², which is more suitable for high-density integration than traditional tapered optical fibers (typical diameter 10μm~20μm); high mechanical robustness: the polymer structure with a Young's modulus of 3GPa~5GPa has a vibration stability that is more than 10 times that of glass optical fibers; strong functional scalability: supports multi-mode interference design, and can simultaneously realize microcavity coupling and wavelength multiplexing functions.

[0027] In addition, the coupling architecture provided by the embodiment of the present invention provides a key enabling technology for building large-scale nonlinear photonic networks (such as optical quantum computing chips and parallel optical frequency comb arrays). Improving nonlinear coefficients) and topology optimization (such as spiral PWB design) will help promote the development of industrial-grade photonic integrated circuits.

[0028] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0030] Figure 1 A schematic structural diagram of a housing of an optical microcavity coupling structure provided by an embodiment of the present invention;

[0031] Figure 2 A schematic diagram of the microstructure of an optical fiber array of an optical microcavity coupling structure provided by an embodiment of the present invention;

[0032] Figure 3 Another microscopic structural schematic diagram of an optical fiber array of an optical microcavity coupling structure provided by an embodiment of the present invention;

[0033] Figure 4 A schematic diagram of the microstructure of an optical microcavity of an optical microcavity coupling structure provided by an embodiment of the present invention;

[0034] Figure 5 A schematic diagram of the microstructure of a photon circuit bonding waveguide and an optical microcavity coupling of an optical microcavity coupling structure provided by an embodiment of the present invention;

[0035] Figure 6 A schematic flow chart of a packaging method for an optical microcavity coupling structure based on a photonic circuit bonding waveguide provided in an embodiment of the present invention;

[0036] Figure 7 A schematic diagram of the structure of an optical path device when a photonic circuit bonding waveguide is coupled to an optical microcavity provided by an embodiment of the present invention;

[0037] Figure 8 A schematic diagram of the quality factor of an optical microcavity after packaging provided by an embodiment of the present invention;

[0038] Among them, 10-shell, 11-base, 12-top cover, 111-support platform, 20-optical fiber array, 21-optical fiber, 22-photon circuit bonding waveguide, 30-optical microcavity, 100-signal generator, 200-laser, 300-attenuator, 400-polarization controller, 500-beam splitter, 600-Mach Zehnder interferometer, 710-first photodetector, 720-second photodetector, 800-oscilloscope. DETAILED DESCRIPTION

[0039] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0040] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0041] In order to solve the coupling problem of optical microcavities in the prior art, an embodiment of the present invention provides an optical microcavity coupling structure based on photonic circuit bonding waveguides, which encapsulates the photonic circuit bonding (PWB) waveguide and the optical microcavity together, providing an alternative and more flexible coupling solution. The optical microcavity coupling structure based on photonic circuit bonding waveguides provided by the embodiment of the present invention includes a housing, an optical fiber array and an optical microcavity; the housing includes a base and a top cover, the base is provided with a support platform, and the optical microcavity is fixed to the surface of the support platform; the first end of the optical fiber array includes a curved photonic circuit bonding waveguide, the two ends of the photonic circuit bonding waveguide are respectively connected to the two optical fibers of the optical fiber array, the first end of the optical fiber array is fixed to the surface of the support platform, the curved area of ​​the photonic circuit bonding waveguide is coupled with the optical microcavity, and the photonic circuit bonding waveguide is suspended; the first end of the optical fiber array, the photonic circuit bonding waveguide and the optical microcavity are encapsulated in the housing formed by the base and the top cover, and the second end of the optical fiber array extends to the outside of the housing.

[0042] For example, Figure 1 A schematic structural diagram of a housing of an optical microcavity coupling structure provided by an embodiment of the present invention, Figure 2 A schematic diagram of the microstructure of an optical fiber array of an optical microcavity coupling structure provided by an embodiment of the present invention, Figure 3 Another microscopic structural diagram of an optical fiber array of an optical microcavity coupling structure provided by an embodiment of the present invention, Figure 4A schematic diagram of the microstructure of an optical microcavity of an optical microcavity coupling structure provided by an embodiment of the present invention, Figure 5 A schematic diagram of the microstructure of a photon circuit bonding waveguide and an optical microcavity coupling structure provided by an embodiment of the present invention, with reference to Figure 1 The housing 10 includes a base 11 and a top cover 12. The base 11 is provided with a support platform 111. The optical microcavity is fixed to the surface of the support platform 111 ( Figure 1 The optical microcavity and optical fiber array are not shown in FIG. Figure 2 and Figure 3 The optical fiber array 20 includes a plurality of optical fibers 21 arranged in parallel. The first end of the optical fiber array 20 includes a curved photon circuit bonding waveguide 22. The two ends of the photon circuit bonding waveguide 22 are respectively connected to the two optical fibers 21 of the optical fiber array 20 ( Figure 2 and Figure 3 FIG. 2 schematically shows that the photon circuit bonding waveguide 22 is connected to two adjacent optical fibers 21, which is not a limitation of the present invention. Figure 4 The optical microcavity 30 may be an on-chip integrated silicon oxide microring core cavity. In this embodiment, the core layer thickness of the silicon oxide microring core cavity is 8 μm, the ring diameter is 1630 μm, and the optical microcavity 30 further includes a substrate and a support column ( Figure 4 (not shown), the material of the substrate and the support column can be silicon. In other embodiments, the specific size of the optical microcavity 30 can be designed according to actual conditions. Figure 5 During coupling, the first end of the optical fiber array 20 and the optical microcavity 30 are fixed to the surface of the support platform 111. Optionally, the optical microcavity 30 can be fixed to the surface of the support platform 111 by a heat-conductive double-sided adhesive. The optical fiber array 20 includes a glass shell, and the glass shell is fixed to the surface of the support platform 111 by a UV-curing adhesive. The curved area of ​​the photon circuit bonding waveguide 22 is coupled to the optical microcavity 30, and the photon circuit bonding waveguide 22 is suspended. After the coupling is completed, the first end of the optical fiber array 20, the photon circuit bonding waveguide 22 and the optical microcavity 30 are encapsulated in the housing 10 formed by the base 11 and the top cover 12, and the second end of the optical fiber array 20 extends to the outside of the housing 10.

[0043] Among them, PWB is an additive 3D manufactured structure capable of guiding light in a free-form configuration. Utilizing a proprietary negative photoresist, similar to SU-8, these PWBs can be written directly on the surface of optical fiber arrays (FAs) or even PICs through a two-photon polymerization process.

[0044] The technical solution of the embodiment of the present invention is to couple the bending area of ​​the photonic circuit bonding waveguide with the optical microcavity by fixing the optical microcavity and the first end of the optical fiber array to the surface of the support platform, and the photonic circuit bonding waveguide is suspended; by encapsulating the first end of the optical fiber array, the photonic circuit bonding waveguide and the optical microcavity inside a shell formed by the base and the top cover, and extending the second end of the optical fiber array to the outside of the shell, the anti-interference of the coupling between the optical microcavity and the photonic circuit bonding waveguide is enhanced, and the coupling efficiency and the stability of the quality factor of the optical microcavity are ensured. The technical solution of the embodiment of the present invention realizes efficient evanescent coupling between PWB and optical microcavity, and provides a solution for the large-scale integration of on-chip optical microcavity and integrated photonics system. Compared with the coupling between PWB and crystal, the optical microcavity provided by the embodiment of the present invention is on-chip integrated, which is more conducive to mass production and reduces costs.

[0045] Continue to refer Figure 2 and Figure 3 Optionally, the photon circuit bonding waveguide 22 is in a U-shape. Optionally, the bending diameter of the photon circuit bonding waveguide 22 is 127 μm, the waveguide diameter is 2 μm, and the insertion loss is less than or equal to 2.5 dB.

[0046] Optionally, the photonic circuit bonding waveguide is formed by using a negative photoresist through a femtosecond laser direct writing technique or a two-photon polymerization direct writing technique.

[0047] In the specific implementation, negative photoresist was used to prepare the following on the end face of customized fiber array (FA) by two-photon polymerization direct writing technology: Figure 2 and Figure 3 The U-bend waveguide PWB structure shown in the figure. The key parameters of the structure are as follows: U-bend diameter: 127μm (matching the standard fiber array spacing), waveguide diameter: 2μm, insertion loss: 2.5dB (including fiber-PWB-fiber end-to-end loss).

[0048] Furthermore, in other embodiments, the nonlinear coefficient and topology optimization can be improved by material modification, which is beneficial to promote the development of industrial-grade photonic integrated circuits. For example, germanium dioxide ( ) to improve the nonlinear coefficient of PWB, the shape of the photonic circuit bonding waveguide can be set to include a spiral shape, and the specific implementation can be designed according to actual conditions.

[0049] use Figure 2 The fiber array and Figure 4 Before coupling, the evanescent field mode distribution of the prepared PWB curved waveguide is simulated using commercial optical simulation software to optimize its coupling efficiency with the optical microcavity.

[0050] Figure 6A schematic diagram of a packaging method for an optical microcavity coupling structure based on a photonic circuit bonding waveguide provided in an embodiment of the present invention is provided, which is used to package the optical microcavity coupling structure provided in the above embodiment, with reference to Figure 6 , the packaging method includes:

[0051] S110, providing a housing, an optical fiber array and an optical microcavity, wherein the housing includes a base and a top cover, the base is provided with a support platform, and the first end of the optical fiber array includes a curved photonic circuit bonding waveguide.

[0052] The shell reference Figure 1 As shown, the housing is manufactured by aluminum alloy CNC machine tools and consists of a base 11 and a top cover 12. The design of the packaging housing mainly complies with three design elements: flexible operation, stable coupling structure and isolation from the outside world. Figure 2 and Figure 3 As shown in the figure, a U-bend waveguide PWB structure is prepared on the end face of a customized fiber array (FA) using negative photoresist by two-photon polymerization direct writing technology. The key parameters of the structure are as follows: U-bend diameter: 127μm (matching the standard fiber array spacing), waveguide diameter: 2μm, insertion loss: 2.5dB (including fiber-PWB-fiber end-to-end loss). Optical microcavity reference Figure 4 As shown, in this embodiment, the optical microcavity is an on-chip integrated silicon oxide microring core cavity, the core layer thickness of the silicon oxide microring core cavity is 8 μm, and the ring diameter is 1630 μm ( before reflow).

[0053] S120, fixing the optical microcavity on the surface of the support platform.

[0054] Specifically, it can be fixed on the surface of the support platform using a thermally conductive double-sided adhesive.

[0055] S130, placing the first end of the optical fiber array on the surface of the support platform, adjusting the coupling between the photon circuit bonding waveguide and the optical microcavity, and then fixing the first end of the optical fiber array on the surface of the support platform.

[0056] After the optical microcavity is fixed, the base of the fixed microcavity sample is placed on the precision translation stage. Figure 7 Schematic diagram of the optical path device structure when the photonic circuit bonding waveguide is coupled with the optical microcavity provided in the embodiment of the present invention, refer to Figure 7The optical path device includes a signal generator 100, a laser 200, an attenuator 300, a polarization controller 400, a beam splitter 500, a Mach-Zehnder interferometer 600, a first photodetector 710, a second photodetector 720 and an oscilloscope 800. The photon circuit bonding waveguide 22 is connected to the optical path, and the optical microcavity 30 is arranged close to the photon circuit bonding waveguide 22. The signal generator 100 is used to provide a scanning piezoelectric signal to the laser 200. The light beam emitted by the laser 200 is attenuated by the attenuator 300 and the polarization state is adjusted by the polarization controller 400 before being incident on the beam splitter 500. The beam splitter 500 can be a 10:90 beam splitter, 10% of the light intensity is transmitted to the Mach-Zehnder interferometer 600, and 90% of the light intensity is transmitted to the photon circuit bonding waveguide 22. The coupling condition is determined by monitoring the signals of the first photodetector 710 and the second photodetector 720 received by the oscilloscope 800.

[0057] Optionally, placing the first end of the optical fiber array on the surface of the support platform, adjusting the coupling between the photon circuit bonding waveguide and the optical microcavity, and then fixing the first end of the optical fiber array on the surface of the support platform comprises:

[0058] S131. Use a clamp to clamp the optical fiber array and place it on the surface of the support table.

[0059] The optical fiber array also includes a glass shell. The optical fiber array is first clamped by a clamp, and the first end of the optical fiber array is placed on the surface of the support table so that the photon circuit bonding waveguide and the optical microcavity are at a relatively close position.

[0060] S132. Use a three-dimensional translation stage and a piezoelectric displacement stage to control the movement of the base so that the optical microcavity is coupled with the curved region of the photonic circuit bonding waveguide.

[0061] While controlling the base to move, observe Figure 7 The waveform of the oscilloscope 800 is used to determine the coupling status of the optical microcavity and the photonic circuit bonding waveguide.

[0062] S133, monitoring the coupling state of the optical microcavity and the photonic circuit bonding waveguide, and when the target coupling state is reached, fixing the first end of the optical fiber array to the surface of the support platform.

[0063] Among them, the photon circuit bonding waveguide is suspended. When the target coupling state is reached, UV curing glue EMI 3410 is applied between the glass shell of the optical fiber array and the base of the shell, and the optical fiber array is fixed on the base of the shell by UV irradiation, and the coupling between the silica micro-ring core cavity and the PWB curved waveguide structure is fixed.

[0064] S140, encapsulating the first end of the optical fiber array, the photonic circuit bonding waveguide and the optical microcavity in a housing formed by the base and the top cover, and extending the second end of the optical fiber array to the outside of the housing.

[0065] Figure 8 A schematic diagram of the quality factor of an optical microcavity after packaging provided by an embodiment of the present invention, wherein the intrinsic quality factor of the optical microcavity is =3.3×10 7 , coupling quality factor Q = 2.6 × 10 7 The experimental results show that the coupling structure provided by the embodiment of the present invention achieves a coupling efficiency of more than 90% in the 1550nm band, while maintaining the intrinsic Q value of the optical microcavity>10 7 . PWB technology can flexibly construct low-loss (<2.5dB) optical interconnect structures in three-dimensional space through additive manufacturing processes such as femtosecond laser direct writing or two-photon polymerization. Its core advantages are: low manufacturing cost: no complex alignment process is required, and single-step molding solves the problem of sub-micron precision positioning required for traditional split optical fibers; small size: the cross-sectional size can be compressed to 1×2μm², which is more suitable for high-density integration than traditional tapered optical fibers (typical diameter 10μm~20μm); high mechanical robustness: the polymer structure with a Young's modulus of 3GPa~5GPa has a vibration stability that is more than 10 times that of glass optical fibers; strong functional scalability: supports multi-mode interference design, and can simultaneously realize microcavity coupling and wavelength multiplexing functions.

[0066] In addition, the coupling architecture provided by the embodiment of the present invention provides a key enabling technology for building large-scale nonlinear photonic networks (such as optical quantum computing chips and parallel optical frequency comb arrays). Improving nonlinear coefficients) and topology optimization (such as spiral PWB design) will help promote the development of industrial-grade photonic integrated circuits.

[0067] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An optical microcavity coupling structure based on photonic circuit bonding waveguide, characterized in that: It includes a housing, an optical fiber array and an optical microcavity; The housing comprises a base and a top cover, the base is provided with a support platform, and the optical microcavity is fixed on the surface of the support platform; The first end of the optical fiber array comprises a photon circuit bonding waveguide in a curved shape, the two ends of the photon circuit bonding waveguide are respectively connected to two optical fibers of the optical fiber array, the first end of the optical fiber array is fixed to the surface of the support platform, the curved region of the photon circuit bonding waveguide is coupled to the optical microcavity, and the photon circuit bonding waveguide is suspended; The first end of the optical fiber array, the photonic circuit bonding waveguide and the optical microcavity are packaged inside the housing formed by the base and the top cover, and the second end of the optical fiber array extends to the outside of the housing.

2. The optical microcavity coupling structure based on photonic circuit bonding waveguide according to claim 1, characterized in that: The photon circuit bonding waveguide is in a U shape.

3. The optical microcavity coupling structure based on photonic circuit bonding waveguide according to claim 2, characterized in that: The bending diameter of the photon circuit bonding waveguide is 127 μm, the waveguide diameter is 2 μm, and the insertion loss is less than or equal to 2.5 dB.

4. The optical microcavity coupling structure based on photonic circuit bonding waveguide according to claim 1, characterized in that: The shape of the photonic circuit bonding waveguide includes a spiral shape.

5. The optical microcavity coupling structure based on photonic circuit bonding waveguide according to claim 1, characterized in that: The photon circuit bonding waveguide is formed by using negative photoresist through femtosecond laser direct writing technology or two-photon polymerization direct writing technology.

6. The optical microcavity coupling structure based on photonic circuit bonding waveguide according to claim 5, characterized in that: The negative photoresist is doped with germanium dioxide.

7. The optical microcavity coupling structure based on photonic circuit bonding waveguide according to claim 1, characterized in that: The optical microcavity is fixed to the surface of the support platform by means of a heat-conductive double-sided adhesive, and the optical fiber array comprises a glass shell, which is fixed to the surface of the support platform by means of an ultraviolet curing adhesive.

8. The optical microcavity coupling structure based on photonic circuit bonding waveguide according to claim 1, characterized in that: The optical microcavity comprises an on-chip integrated silicon oxide microring core cavity, the core layer thickness of the silicon oxide microring core cavity is 8 μm, and the ring diameter is 1630 μm.

9. A packaging method for an optical microcavity coupling structure based on a photonic circuit bonding waveguide, characterized in that: Used to encapsulate the optical microcavity coupling structure according to any one of claims 1 to 8, the encapsulation method comprising: A housing, an optical fiber array and an optical microcavity are provided, wherein the housing comprises a base and a top cover, the base is provided with a support platform, and the first end of the optical fiber array comprises a photonic circuit bonding waveguide with a bent shape; Fixing the optical microcavity on the surface of the support platform; Placing the first end of the optical fiber array on the surface of the support platform, adjusting the coupling between the photonic circuit bonding waveguide and the optical microcavity, and then fixing the first end of the optical fiber array on the surface of the support platform; The first end of the optical fiber array, the photon circuit bonding waveguide and the optical microcavity are encapsulated inside the housing formed by the base and the top cover, and the second end of the optical fiber array extends to the outside of the housing.

10. The packaging method according to claim 9, characterized in that: Placing the first end of the optical fiber array on the surface of the support platform, adjusting the coupling between the photonic circuit bonding waveguide and the optical microcavity, and fixing the first end of the optical fiber array on the surface of the support platform, comprising: Clamp the optical fiber array with a fixture and place it on the surface of the support platform; Using a three-dimensional translation stage and a piezoelectric displacement stage to control the movement of the base so that the optical microcavity is coupled with the curved region of the photonic circuit bonding waveguide; monitoring the coupling state of the optical microcavity and the photonic circuit bonding waveguide, and when a target coupling state is reached, fixing the first end of the optical fiber array to the surface of the support platform; Wherein, the photonic circuit bonding waveguide is suspended.

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