On-chip narrow linewidth laser for quantum technology

Abstract

The present application belongs to the field of optical engineering and quantum information, and particularly relates to a kind of on-chip narrow linewidth laser for atomic quantum technology.Laser includes laser chip, linewidth compression module, temperature control module and electronic control module integrated on laser substrate;Laser chip is used to generate seed laser, linewidth compression module is used to realize the linewidth compression of seed laser, and the output end of linewidth compression module is finally connected to fiber or waveguide to couple the compressed laser to off-chip output;Temperature control module is used to control and adjust the temperature of laser chip region and linewidth compression region;Electronic control module is electrically connected with laser chip, linewidth compression module and temperature control module to accurately control the applied current of each module.

Description

Technical Field

[0001] This invention belongs to the fields of optical engineering and quantum information, and particularly relates to an on-chip narrow linewidth laser for atomic quantum technology. Background Technology

[0002] Narrow-linewidth lasers, with their high coherence and low phase noise, are core devices in quantum communication, computing, and sensing, and their performance directly determines the core indicators of quantum systems. In quantum communication, they influence key distribution distance and security; in quantum computing, they ensure the precision of quantum state manipulation; and in quantum sensing, they determine measurement resolution and sensitivity.

[0003] Existing narrow-linewidth lasers are mainly divided into three categories: discrete-component external-cavity lasers, monolithically integrated lasers (such as DFB and DBR types), and silicon-based photonic chip (SPC) external-cavity quasi-monolithically integrated lasers. Discrete-component lasers have narrow linewidths but are large in size and have low reliability, making them unsuitable for integration requirements; monolithically integrated lasers have high integration density, but their linewidths are difficult to reach below the kHz level, and their tuning range is limited, failing to meet the needs of mid-to-high-end quantum technologies.

[0004] The development of quantum technology places higher demands on lasers: they need extremely narrow linewidths on the order of kHz, high frequency stability, high integration, small size and low power consumption, as well as wide tuning range and high output power, in order to adapt to diverse scenarios and reduce deployment costs.

[0005] In summary, existing solutions are unable to meet core requirements such as integration density and narrow linewidth, and cannot satisfy the practical applications of quantum technology. Developing a high-performance on-chip narrow linewidth laser has become an urgent problem to be solved in this field. Summary of the Invention

[0006] This invention addresses the shortcomings of existing technologies by proposing an on-chip narrow-linewidth laser for quantum technology. Through optoelectronic integration technology, core modules such as the laser chip, linewidth narrowing module, and laser amplification chip are integrated on-chip, significantly reducing the size, weight, power consumption, and cost of the narrow-linewidth laser. This provides technical support for the miniaturization, integration, and large-scale deployment of quantum technology.

[0007] The technical solution of the present invention is: an on-chip narrow linewidth laser for quantum technology, comprising a laser chip, a linewidth narrowing module, a temperature control module and an electronic control module integrated on a laser substrate; The laser chip is used to generate seed laser. The linewidth narrowing module is used to narrow the linewidth of the seed laser. The output of the linewidth narrowing module is ultimately connected to an optical fiber or waveguide to couple the narrowed laser to an off-chip output. The temperature control module is used to control and adjust the temperature of the laser chip area and the linewidth narrowing area; The electronic control module is electrically connected to the laser chip, the linewidth narrowing module, and the temperature control module to precisely control the applied current of each module.

[0008] As a preferred embodiment, the linewidth narrowing module includes a frequency control component for tuning the center wavelength of the final output of the linewidth narrowing structure and an on-chip micro-resonator mechanism; the laser chip and the on-chip micro-resonator mechanism are interconnected through an on-chip waveguide; and the frequency control component is provided on both the on-chip waveguide and the on-chip micro-resonator mechanism.

[0009] As a preferred embodiment, the system further includes a laser amplification chip positioned before the linewidth narrowing module. The laser amplification chip is used to amplify the power of the seed laser coupled into it after linewidth narrowing. The temperature control module adjusts the temperature of the laser amplification chip region. The electronic control module is electrically connected to the laser amplification chip to precisely control the applied current thereon.

[0010] As another preferred embodiment, a laser amplification chip is also included after the linewidth narrowing module. The laser amplification chip is used to amplify the power of the linewidth narrowed seed laser coupled into it. The temperature control module adjusts the temperature of the laser amplification chip area. The electronic control module is electrically connected to the laser amplification chip to precisely control the applied current thereon. The laser amplification chip is connected to the optical fiber or the waveguide to couple the amplified laser to an off-chip output.

[0011] As a preferred embodiment, the laser chip, the on-chip microresonator, and the laser amplification chip are interconnected via the on-chip waveguide.

[0012] As a preferred embodiment, the on-chip microresonator is a microring, a microFP cavity, or a low-loss fiber optic loop.

[0013] As a preferred embodiment, the frequency control component is a precision heating module used for resonant microrings and optical waveguides.

[0014] As a preferred embodiment, the active region of the laser chip and the laser amplification chip are shared.

[0015] As a preferred embodiment, the active regions of the laser chip and the laser amplification chip are made of GaN, GaAs, InP, or quantum dots.

[0016] Compared with the prior art, the present invention provides an on-chip narrow linewidth laser for atomic quantum technology, which has the following advantages: 1. On-chip synergy between narrow linewidth and wavelength tuning: Through the cooperation of on-chip micro-resonator and frequency control components, kHz-level linewidth and wide tuning range are achieved in an integrated architecture, breaking through the traditional trade-off between narrow linewidth and tunability of DFB / DBR lasers.

[0017] 2. Enhanced frequency stability through all-solid-state self-injection locking: The on-chip micro-resonator also serves as a high-Q external cavity feedback element, forming optical feedback locking for the laser chip. This eliminates the need for complex external frequency stabilization circuits. Furthermore, the on-chip structure isolates the optical path from the interference of mechanical vibration and temperature drift, effectively improving the long-term frequency stability of the light source.

[0018] 3. Heterogeneous integration architecture reduces size and coupling loss: By integrating III-V group gain chips with passive photonic platforms on-chip, optical path alignment is completed at the manufacturing level in one step, avoiding assembly and adjustment errors and coupling losses of discrete components in the spatial optical path, and significantly reducing the device's SWaP (size, weight and power consumption) while maintaining narrow linewidth performance. Attached Figure Description

[0019] Figure 1 A schematic diagram of an on-chip narrow linewidth laser is shown when high power output is required.

[0020] Figure 2 This diagram illustrates another structural schematic of an on-chip narrow linewidth laser when high power output is required.

[0021] Figure 3 A schematic diagram of an on-chip narrow linewidth laser is shown when high power output is not required.

[0022] In the figure, 1 is the laser chip; 2 is the on-chip waveguide; 3 is the frequency control component; 4 is the on-chip micro-resonator mechanism; 5 is the laser amplifier chip; 6 is the laser substrate; 7 is the electronic control module; and 8 is the temperature control module. Detailed Implementation

[0023] To better understand the present invention, specific embodiments will be given to further illustrate the invention. However, it should be understood that the described embodiments are exemplary embodiments, and the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0024] In the embodiments of the present invention, unless otherwise specified and limited, it should be noted that the term "on-chip integration" should be interpreted broadly, and can refer to "2.5D interposer integration," "wafer-level material heterogeneous bonding," and "optoelectronic hybrid heterogeneous integration." Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0025] Example 1 is an embodiment requiring higher laser power for quantum applications. See the detailed structure below. Figure 1 An on-chip narrow linewidth laser for quantum technology includes a laser chip 1, a linewidth narrowing module, a laser amplification chip 5, a temperature control module 8, and an electronic control module integrated on a laser substrate 6. Laser chip 1 is used to generate seed laser, and linewidth narrowing module is used to narrow the linewidth of seed laser. The linewidth narrowing module includes a frequency modulation component 3 for tuning the center wavelength of the final output of the linewidth narrowing structure and an on-chip micro-resonator mechanism 4. The laser amplification chip 5 is used to amplify the power of the seed laser whose linewidth has been narrowed after coupling into it; the laser chip 1, the on-chip micro-resonator 4, and the laser amplification chip 5 are interconnected through the on-chip waveguide 2; frequency control components 3 are provided on both the on-chip waveguide 2 and the on-chip micro-resonator 4.

[0026] The laser amplification chip 5 is connected to an optical fiber or waveguide to couple the narrowed laser to an off-chip output; the temperature control module 8 is used to control and adjust the temperature of the laser chip 1 region and the linewidth narrowing region. The electronic control module is electrically connected to the laser chip 1, the linewidth narrowing module, the laser amplification chip 5, and the temperature control module 8 to precisely control the applied current of each module.

[0027] During operation, laser chip 1 generates a seed laser, which is then transmitted through on-chip waveguide 2 to on-chip micro-resonator 4 for linewidth narrowing. The linewidth narrowed laser is then coupled to laser amplifier chip 5 through waveguide or spatial coupling for power amplification. Finally, the laser power is coupled out through on-chip waveguide or optical fiber. To achieve tuning of the output wavelength, frequency control components 3 are fabricated on both on-chip waveguide 2 and on-chip micro-resonator 4. Taking a micro-ring as an example of a resonant structure, the frequency control component 3 is a heating component. By changing the temperature environment of the waveguide and micro-ring, the cavity length and refractive index are adjusted, ultimately achieving tuning of the wavelength that can be transmitted via wave switching.

[0028] Example 2 is another embodiment requiring higher laser power for quantum applications. See the detailed structure below. Figure 2 An on-chip narrow linewidth laser for quantum technology includes a laser chip 1, a laser amplification chip 5, a linewidth narrowing module, a temperature control module 8, and an electronic control module integrated on a laser substrate 6. Laser chip 1 is used to generate seed laser. The laser amplification chip 5 is used to amplify the power of the seed laser coupled into it; The linewidth narrowing module is located after the laser amplification chip 5. The linewidth narrowing module is used to narrow the linewidth of the seed laser amplified by the laser amplification chip 5. The output of the linewidth narrowing module is ultimately connected to an optical fiber or waveguide to couple the narrowed laser to an off-chip output. Temperature control module 8 is used to control and adjust the temperature of the laser chip 1 region and the linewidth narrowing region; The electronic control module is electrically connected to the laser chip 1, the linewidth narrowing module, the laser amplification chip 5, and the temperature control module 8 to precisely control the applied current of each module.

[0029] In operation, the only difference between this and Example 1 is the exchange of the order of linewidth narrowing and laser power amplification.

[0030] Example 3 Figure 3 The illustration shows an embodiment requiring lower laser power for quantum applications. An on-chip narrow-linewidth laser for quantum technology includes a laser chip 1, a linewidth narrowing module, a temperature control module 8, and an electronic control module integrated on a laser substrate 6. Laser chip 1 is used to generate seed laser; linewidth narrowing module is used to narrow the linewidth of seed laser; The output of the linewidth narrowing module is finally connected to an optical fiber or waveguide to couple the narrowed laser to an off-chip output; the linewidth narrowing module includes a frequency control component 3 for tuning the center wavelength of the final output of the linewidth narrowing structure and an on-chip micro-resonator mechanism 4; the laser chip 1 and the on-chip micro-resonator mechanism 4 are interconnected through an on-chip waveguide 2; the frequency control component 3 is provided on both the on-chip waveguide 2 and the on-chip micro-resonator mechanism 4.

[0031] Temperature control module 8 is used to control and adjust the temperature of the laser chip 1 region and the linewidth narrowing region; the electronic control module is electrically connected to the laser chip 1, the linewidth narrowing module, and the temperature control module 8 respectively to precisely control the applied current of each module.

[0032] Laser chip 1 generates a seed laser, which is then transmitted to on-chip micro-resonator 4 via on-chip waveguide 2 for linewidth narrowing. The linewidth narrowed laser is then coupled and output through waveguide or optical fiber. Frequency control component 3 is a heating component that adjusts the cavity length and refractive index by changing the temperature environment of the waveguide and micro-ring, ultimately achieving the tuning of the wavelength that can be transmitted via wave switching.

[0033] The above are merely embodiments of the present invention and are 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 principle of the present invention should be included within the scope of the claims of this application.

Claims

1. An on-chip narrow linewidth laser for quantum technology, characterized in that, This includes laser chips, linewidth narrowing modules, temperature control modules, and electronic control modules integrated on the laser substrate; The laser chip is used to generate seed laser; The linewidth narrowing module is used to narrow the linewidth of the seed laser; The output of the linewidth narrowing module is ultimately connected to an optical fiber or waveguide to couple the narrowed laser to an off-chip output. The temperature control module is used to control and adjust the temperature of the laser chip area and the linewidth narrowing area; The electronic control module is electrically connected to the laser chip, the linewidth narrowing module, and the temperature control module to precisely control the applied current of each module.

2. The on-chip narrow linewidth laser for quantum technology according to claim 1, characterized in that, The linewidth narrowing module includes a frequency control component for tuning the center wavelength of the final output of the linewidth narrowing structure and an on-chip micro-resonator mechanism; the laser chip and the on-chip micro-resonator mechanism are interconnected through an on-chip waveguide; the frequency control component is provided on both the on-chip waveguide and the on-chip micro-resonator mechanism.

3. The on-chip narrow linewidth laser for quantum technology according to claim 2, characterized in that, It also includes a laser amplification chip disposed before the linewidth narrowing module. The laser amplification chip is used to amplify the power of the seed laser coupled into it after linewidth narrowing. The temperature control module adjusts the temperature of the laser amplification chip area. The electronic control module is electrically connected to the laser amplification chip to precisely control the applied current thereon.

4. An on-chip narrow linewidth laser for quantum technology according to claim 2, characterized in that, It also includes a laser amplification chip disposed after the linewidth narrowing module. The laser amplification chip is used to amplify the power of the seed laser coupled into it after the linewidth narrowing. The temperature control module adjusts the temperature of the laser amplification chip area. The electronic control module is electrically connected to the laser amplification chip to precisely control the applied current thereon. The laser amplification chip is connected to the optical fiber or the waveguide to couple the amplified laser to an off-chip output.

5. An on-chip narrow linewidth laser for quantum technology according to claim 4, characterized in that, The laser chip, the on-chip microresonator, and the laser amplifier chip are interconnected via the on-chip waveguide.

6. An on-chip narrow linewidth laser for quantum technology according to claim 2, characterized in that, The on-chip micro-resonant mechanism is a micro-ring, a micro-FP cavity, or a low-loss fiber optic loop.

7. An on-chip narrow linewidth laser for quantum technology according to claim 6, characterized in that, The frequency control component is a precision heating module used for resonant microrings and optical waveguides.

8. An on-chip narrow linewidth laser for quantum technology according to claim 1, characterized in that, The active regions of the laser chip and the laser amplifier chip are shared.

9. An on-chip narrow linewidth laser for quantum technology according to claim 8, characterized in that, The active regions of the laser chip and the laser amplification chip are made of GaN, GaAs, InP, or quantum dots.

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