Quantum dot mode-locked laser optical frequency comb generation device

Abstract

The utility model discloses a kind of quantum dot mode-locked laser light frequency comb generation device, including quantum dot mode-locked laser, drive unit and control module.Laser inside integrated with miniature semiconductor refrigerator TEC and thermistor;Drive unit is equipped with TEC drive interface and electric pump source drive interface;Control module includes external TEC control unit and external laser control unit.TEC control unit is connected with the TEC and thermistor in the inside of laser through TEC drive interface, constitutes closed loop temperature control;Laser control unit provides independent adjustable voltage and current for laser through electric pump source drive interface, drives and tunes light frequency comb output.The utility model uses quantum dot gain medium and integrated temperature control design with low power consumption, high stability and wide temperature operating characteristics.Light frequency comb parameters can be flexibly adjusted by external electric control;Standardized interface makes compact structure, easy to assemble, significantly reduce cost and complexity.

Description

Technical Field

[0001] This utility model belongs to the field of optoelectronic device technology, and in particular relates to a quantum dot mode-locked laser optical frequency comb generating device. Background Technology

[0002] An optical frequency comb (OFC) is a light source composed of a series of equally spaced, coherent, discrete laser spectral lines. Since its discovery, this technology has brought revolutionary progress to many cutting-edge fields such as precision metrology, spectral analysis, optical atomic clocks, and high-speed optical communication. Its core value lies in its ability to achieve extremely high-precision measurement and manipulation of frequency and time, much like a highly precise "optical ruler." In the field of optical communication, especially in dense wavelength division multiplexing (DWDM) systems, the optical frequency comb can serve as an ideal alternative to multi-wavelength laser arrays. It can generate optical carriers for multiple channels simultaneously, thereby significantly simplifying the transmitter architecture, reducing system power consumption and cost, and naturally maintaining the phase coherence between channels, laying the foundation for the development of next-generation high-speed coherent optical access networks.

[0003] Achieving on-chip integration of optical frequency combs is a key path to promoting their large-scale commercial application. Among various technical solutions, semiconductor mode-locked lasers (MLLs) have attracted widespread attention due to their advantages such as compact size, support for electric pump drive, low cost, and ease of large-scale integration. Short-cavity MLLs, in particular, can directly generate optical frequency combs with repetition rates up to tens of GHz and high optical signal-to-noise ratios (OSNR). Their wide spectral spacing closely matches the standard channel spacing of DWDM systems (e.g., 25 GHz), demonstrating good system compatibility. However, these devices still face significant challenges in practical deployment, namely maintaining stable optical frequency comb output within an industrial-grade temperature range (e.g., -20°C to 85°C) without additional temperature control measures to meet the environmental adaptability requirements of practical applications.

[0004] On the other hand, current solutions based on multi-wavelength laser micro-assembly technology have significant limitations in practical applications due to issues such as high power consumption, high cost, and limited scalability. Specifically, such solutions typically require integrating multiple discrete laser chips through packaging to achieve multi-wavelength emission functionality. Constrained by single-chip yield and wavelength consistency requirements, a large number of laser units must be screened and matched during actual manufacturing, leading to high process complexity and a significant increase in overall cost, thus hindering its large-scale application in high-speed optical communication systems. Utility Model Content

[0005] To address the above technical problems, this utility model provides a quantum dot mode-locked laser optical frequency comb generating device.

[0006] The technical solution adopted by this utility model to solve its technical problem is:

[0007] A quantum dot mode-locked laser optical frequency comb generating device includes: a quantum dot mode-locked laser, a driving unit, and a control module;

[0008] The quantum dot mode-locked laser integrates a miniature semiconductor cooler (TEC) and a thermistor.

[0009] The drive unit includes a TEC drive interface and an electric pump source drive interface;

[0010] The control module includes an external TEC control unit and an external laser control unit. The external TEC control unit is connected to a miniature semiconductor cooler and a thermistor via a TEC drive interface to receive temperature feedback signals and output temperature control current. The external laser control unit is connected to a quantum dot mode-locked laser via an electric pump source drive interface to provide adjustable operating voltage and current to drive the laser to emit light and adjust the output optical frequency comb.

[0011] Preferably, the gain medium of the quantum dot mode-locked laser is InAs / InGaAs quantum dot material.

[0012] Preferably, the control current output from the external TEC control unit to the micro semiconductor cooler ranges from -1.2A to +1.2A, the voltage ranges from -4V to +4V, the temperature control resolution reaches 0.001℃, and the temperature stability is controlled below 0.005℃.

[0013] Preferably, the external laser control unit includes a voltage source and a current source. The adjustable output voltage window of the voltage source is 0 to -6V, and the voltage setting resolution is no greater than 0.01V. The adjustable output current window of the current source is 0 to 500mA, and the current resolution is no greater than 0.01mA.

[0014] Preferably, the quantum dot mode-locked laser has multiple external electrical connection pins, wherein the first pin is defined as TEC+, which is connected to the positive terminal of the micro-semiconductor cooler; the fourteenth pin is defined as TEC-, which is connected to the negative terminal of the micro-semiconductor cooler; the second and fifth pins are defined as thermistor interfaces, which are connected to the two terminals of the thermistor; the sixth pin is defined as the positive voltage input terminal V+; the ninth pin is defined as the common ground terminal GND; and the tenth pin is defined as the positive current input terminal I+.

[0015] Preferably, the first pin and the fourteenth pin are connected to the current output terminal of an external TEC control unit through the TEC drive interface of the drive unit;

[0016] The second and fifth pins are connected to the feedback signal input of an external TEC control unit via a drive unit;

[0017] Pin 6 and pin 10 are connected to the voltage source and current source of the external laser control unit, respectively, through the electric pump source drive interface of the drive unit;

[0018] Pin 9 is grounded via the driver unit.

[0019] Preferably, the quantum dot mode-locked laser achieves passive mode-locking based on an internally integrated nonlinear saturable absorber, directly generating an optical frequency comb with a repetition frequency greater than or equal to 50 GHz.

[0020] Preferably, the device can operate stably in an ambient temperature range of -20°C to 85°C under the regulation of an external TEC control unit.

[0021] Preferably, the number of channels, single-channel power, and wavelength range of the optical frequency comb output by the quantum dot mode-locked laser are adjusted by regulating the operating voltage and operating current output by the external laser control unit.

[0022] Preferably, the quantum dot mode-locked laser, the driving unit, and the control module are mounted on the same circuit board.

[0023] The aforementioned quantum dot mode-locked laser optical frequency comb generation device achieves low power consumption and high temperature stability through an integrated design that combines a quantum dot gain medium with an internally integrated micro TEC and thermistor, ensuring reliable operation within a wide industrial temperature range of -20℃ to 85℃. With the aid of an external independent laser control unit, the injection voltage and current can be precisely adjusted, thereby flexibly controlling the number of channels, single-channel power, and wavelength range of the output optical frequency comb, significantly enhancing adaptability. A single chip generates multiple wavelength frequency combs, and the standardized pin interface design makes the system compact and easy to assemble, greatly improving integration and reducing overall cost. Simultaneously, high-precision TEC control and electric pump source adjustment provide a solid foundation for the long-term stable operation and precise tuning of the optical frequency comb. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of a quantum dot mode-locked laser optical frequency comb generating device in one embodiment of the present invention;

[0025] Figure 2 This is a schematic diagram of a quantum dot mode-locked laser optical frequency comb generating device according to one embodiment of the present invention;

[0026] Figure 3 This is a diagram showing the pin definition of a quantum dot mode-locked laser in one embodiment of the present invention;

[0027] Figure 4 This is a frequency comb spectrum of the quantum dot mode-locked laser output in one embodiment of the present invention. Detailed Implementation

[0028] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings.

[0029] See Figure 1 and Figure 2 This embodiment provides a quantum dot mode-locked laser optical frequency comb generating device. The device adopts a modular design and includes: a quantum dot mode-locked laser 1, a driving unit, and a control module. All modules are mounted on the same circuit board 4, forming a compact and highly integrated optical frequency comb light source system.

[0030] The quantum dot mode-locked laser 1 is the core light source of the device. It not only contains an InAs / InGaAs quantum dot material gain medium and a Fabry-Perot resonant cavity, but also integrates a miniature thermoelectric cooler (TEC) and a thermistor. This laser utilizes an integrated nonlinear saturable absorber within the cavity to achieve self-starting passive mode-locking, directly generating an optical frequency comb with a repetition rate ≥50 GHz without any external modulation devices.

[0031] The drive unit, as the physical carrier of electrical connections, primarily provides two interfaces: the TEC drive interface and the electric pump source drive interface. These interfaces enable a reliable and standardized connection between the core laser and the external control circuitry.

[0032] The control module is responsible for providing precise drive and regulation for the laser, including the external TEC control unit 2 which is responsible for temperature control and the external laser control unit 3 which is responsible for electric pump source and spectral tuning.

[0033] Furthermore, the miniature TEC and thermistor integrated within the quantum dot mode-locked laser constitute a complete temperature control actuator and sensing component. Externally, it is connected via a set of standardized PIN pins (definitions see...). Figure 3 The system is connected, and the key pin definitions are as follows:

[0034] Pin 1 (TEC+) and Pin 14 (TEC-): Connect to the positive and negative terminals of the internal miniature TEC, respectively; Pin 2 and Pin 5: Connect to the two terminals of the internal thermistor (neither positive nor negative), used for temperature signal feedback; Pin 6 (V+): Positive voltage input terminal; Pin 9 (GND): Common ground terminal; Pin 10 (I+): Positive current input terminal.

[0035] The external TEC control unit 2 connects to pins 1, 14, 2, and 5 of the laser via the TEC drive interface of the drive unit, forming a closed-loop temperature control circuit. It reads the temperature signal fed back from the thermistor (pins 2 and 5) in real time and dynamically adjusts the control current of the miniature TEC (pins 1 and 14) to achieve high-precision temperature control. Its performance parameters include: control current range -1.2A to +1.2A, voltage range -4V to +4V, temperature resolution up to 0.001℃, and temperature stability better than 0.005℃. Therefore, the device can operate stably within an industrial-grade wide temperature range of -20℃ to 85℃. The entire temperature control circuit is specifically as follows: laser pins 1 and 14 → TEC drive interface → current output terminal of external TEC control unit 2; laser pins 2 and 5 → TEC drive interface → feedback input terminal of external TEC control unit 2.

[0036] The external laser control unit 3 integrates an electric pump source composed of a high-precision voltage source and a current source. It connects to pins 6 (V+), 10 (I+), and 9 (GND) of the laser via the electric pump source drive interface of the drive unit, providing the bias voltage and injection current required for laser operation. By programming and adjusting the voltage of this unit (voltage range 0 to -6V, minimum resolution 0.01V), and the current range 0 to 500mA, minimum resolution 0.01mA, the laser's operating state can be precisely controlled, thereby enabling flexible tuning of parameters such as the number of channels, single-channel power, and wavelength range of the output optical frequency comb. The entire electric pump source circuit is as follows: laser pin 6 → electric pump source drive interface → positive terminal of the voltage source of the external laser control unit 3; laser pin 10 → electric pump source drive interface → positive terminal of the current source of the external laser control unit 3; laser pin 9 → electric pump source drive interface → common ground.

[0037] Based on the above system, the steps for controlling the output of the quantum dot optical frequency comb laser are as follows:

[0038] Assembly: Assemble the quantum dot mode-locked laser at the corresponding position on the circuit board.

[0039] Connect the temperature control circuit: Connect pin 1 of the laser to the positive drive port of the external TEC control unit, and pin 14 to its negative drive port.

[0040] Connect the electric pump source lines: Connect pin 6 of the laser to the positive terminal of the voltage source of the external laser control unit, pin 10 to the positive terminal of its current source, and pin 9 to the system ground.

[0041] Startup and Control: After power-on, activate the external TEC control unit to stabilize the laser chip temperature at the set value. Simultaneously, set the required operating voltage and current for the laser via the external laser control unit. This will allow you to obtain the optical frequency comb output with the desired characteristics from the fiber optic port at the laser's tail. See the example spectrum below. Figure 4 .

[0042] This invention achieves the following significant advantages through a comprehensive design incorporating quantum dot materials, an integrated TEC (Technology, Energy, and Technology) system, and a standardized pin interface:

[0043] High performance and high stability: Based on quantum dot gain medium and internally integrated high-precision TEC temperature control, it achieves low power consumption and high temperature stability, ensuring reliable operation in industrial temperature environments (-20℃~85℃).

[0044] Highly tunable: The laser's operating voltage and current can be independently adjusted via an external laser control unit, allowing for flexible and precise control of multiple parameters of the output optical frequency comb, making it highly adaptable.

[0045] High integration and low cost: A single chip can output multi-wavelength frequency combs, and the laser integrates temperature control components. It connects to the outside through standardized pins, making the whole device compact, small in size, and easy to assemble, which greatly reduces system complexity and cost.

[0046] Precise control: Both the TEC temperature control and the electric pump source drive have high resolution and wide adjustment range, providing a solid foundation for the stable output and fine tuning of the optical frequency comb.

[0047] The above provides a detailed description of the quantum dot mode-locked laser optical frequency comb generating device provided by this utility model. Specific examples have been used to illustrate the principle and implementation of this utility model. The descriptions of the embodiments above are only for the purpose of helping to understand the core idea of ​​this utility model. It should be noted that those skilled in the art can make several improvements and modifications to this utility model without departing from the principle of this utility model, and these improvements and modifications also fall within the protection scope of the claims of this utility model.

Claims

1. A quantum dot mode-locked laser optical frequency comb generating device, characterized in that, include: Quantum dot mode-locked laser, driving unit, and control module; The quantum dot mode-locked laser integrates a miniature semiconductor cooler (TEC) and a thermistor. The drive unit includes a TEC drive interface and an electric pump source drive interface; The control module includes an external TEC control unit and an external laser control unit. The external TEC control unit is connected to a miniature semiconductor cooler and a thermistor via a TEC drive interface to receive temperature feedback signals and output temperature control current. The external laser control unit is connected to a quantum dot mode-locked laser via an electric pump source drive interface to provide adjustable operating voltage and current to drive the laser to emit light and adjust the output optical frequency comb.

2. The quantum dot mode-locked laser optical frequency comb generating device according to claim 1, characterized in that, The gain medium of the quantum dot mode-locked laser is InAs / InGaAs quantum dot material.

3. The quantum dot mode-locked laser optical frequency comb generating device according to claim 2, characterized in that, The external TEC control unit outputs a control current range of -1.2A to +1.2A and a voltage range of -4V to +4V to the micro-semiconductor cooler. The temperature control resolution reaches 0.001℃ and the temperature stability is controlled below 0.005℃.

4. The quantum dot mode-locked laser optical frequency comb generating device according to claim 3, characterized in that, The external laser control unit includes a voltage source and a current source. The adjustable output voltage window of the voltage source is 0 to -6V, and the voltage setting resolution is no greater than 0.01V. The adjustable output current window of the current source is 0 to 500mA, and the current resolution is no greater than 0.01mA.

5. The quantum dot mode-locked laser optical frequency comb generating device according to claim 4, characterized in that, The quantum dot mode-locked laser has multiple external electrical connection pins. The first pin is defined as TEC+, which is connected to the positive terminal of the micro-thermal cooler; the fourteenth pin is defined as TEC-, which is connected to the negative terminal of the micro-thermal cooler; the second and fifth pins are defined as thermistor interfaces, which are connected to the two terminals of the thermistor; the sixth pin is defined as the positive voltage input terminal V+; the ninth pin is defined as the common ground terminal GND; and the tenth pin is defined as the positive current input terminal I+.

6. The quantum dot mode-locked laser optical frequency comb generating device according to claim 5, characterized in that, Pin 1 and pin 14 are connected to the current output terminal of an external TEC control unit via the TEC drive interface of the drive unit; The second and fifth pins are connected to the feedback signal input of an external TEC control unit via a drive unit; Pin 6 and pin 10 are connected to the voltage source and current source of the external laser control unit, respectively, through the electric pump source drive interface of the drive unit; Pin 9 is grounded via the driver unit.

7. The quantum dot mode-locked laser optical frequency comb generating device according to claim 6, characterized in that, Quantum dot mode-locked lasers achieve passive mode-locking based on an internally integrated nonlinear saturable absorber, directly generating an optical frequency comb with a repetition frequency greater than or equal to 50 GHz.

8. The quantum dot mode-locked laser optical frequency comb generating device according to claim 7, characterized in that, With the adjustment of an external TEC control unit, the device can operate stably in an ambient temperature range of -20℃ to 85℃.

9. The quantum dot mode-locked laser optical frequency comb generating device according to claim 8, characterized in that, By adjusting the operating voltage and current output by the external laser control unit, the number of channels, single-channel power, and wavelength range of the optical frequency comb output by the quantum dot mode-locked laser can be adjusted.

10. The quantum dot mode-locked laser optical frequency comb generating device according to claim 9, characterized in that, The quantum dot mode-locked laser, the driving unit, and the control module are mounted on the same circuit board.

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