WO2016082541A1 - 一种大范围调谐激光器及其调谐方法 - Google Patents

一种大范围调谐激光器及其调谐方法 Download PDF

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WO2016082541A1
WO2016082541A1 PCT/CN2015/082342 CN2015082342W WO2016082541A1 WO 2016082541 A1 WO2016082541 A1 WO 2016082541A1 CN 2015082342 W CN2015082342 W CN 2015082342W WO 2016082541 A1 WO2016082541 A1 WO 2016082541A1
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phase
laser
arm
arms
region
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French (fr)
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国伟华
陈泉安
陆巧银
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华中科技大学
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/06—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium
    • H01S5/065—Mode locking; Mode suppression; Mode selection ; Self pulsating
    • H01S5/0651—Mode control
    • H01S5/0653—Mode suppression, e.g. specific multimode
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/02—Structural details or components not essential to laser action
    • H01S5/026—Monolithically integrated components, e.g. waveguides, monitoring photo-detectors, drivers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/06—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium
    • H01S5/062—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium by varying the potential of the electrodes
    • H01S5/0625—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium by varying the potential of the electrodes in multi-section lasers
    • H01S5/06255—Controlling the frequency of the radiation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/06—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium
    • H01S5/068—Stabilisation of laser output parameters
    • H01S5/06821—Stabilising other output parameters than intensity or frequency, e.g. phase, polarisation or far-fields
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/10—Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region
    • H01S5/1003—Waveguide having a modified shape along the axis, e.g. branched, curved, tapered, voids
    • H01S5/1007—Branched waveguides
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/10—Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region
    • H01S5/1028—Coupling to elements in the cavity, e.g. coupling to waveguides adjacent the active region, e.g. forward coupled [DFC] structures
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/06—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium
    • H01S5/065—Mode locking; Mode suppression; Mode selection ; Self pulsating
    • H01S5/0651—Mode control
    • H01S5/0653—Mode suppression, e.g. specific multimode
    • H01S5/0654—Single longitudinal mode emission

Definitions

  • the invention relates to the technical field of large-range wavelength tunable lasers, and relates to a wide-range wavelength tunable laser and a tuning method thereof.
  • DWDM Dense Wavelength Division Multiplexing
  • tuned lasers can replace multiple wavelength-fixed lasers, which not only greatly reduces the cost of the backup source, but also provides timely and efficient inventory management and fast channel setup.
  • tuned lasers also provide automatic wavelength configuration, wavelength conversion, and wavelength routing to increase network flexibility and bandwidth utilization. In recent decades, tuned lasers have received extensive attention and research at home and abroad.
  • the tuned laser can be composed of the most basic Fabry-Pérot (F-P) cavity laser, phase controller and mode selection filter.
  • the F-P cavity laser consists only of the gain medium and the resonant cavity (consisting of mirrors at both ends), and there are many wavelengths (longitudinal modes of the laser) that satisfy the operating conditions of the laser. Since the gain spectrum of the semiconductor gain medium is generally flat, as shown by the gain spectrum in Figure 1, the conventional F-P cavity laser does not have a mode selection mechanism, and is generally multimode lasing. In order to achieve single longitudinal mode lasing, a mode selection filter is required to select a single longitudinal mode.
  • the center wavelength of the filter is close to the mode to be selected, so that the extra loss caused by the filter is smaller than other modes, and thus dominates the laser lasing spectrum.
  • the ratio of the output power of this mode to the output power of other modes is usually called the Side Mode Suppression Ratio (SMSR).
  • SMSR Side Mode Suppression Ratio
  • Different longitudinal modes can be selected for lasing by adjusting the center wavelength of the filter. This adjustment is often referred to as the coarse adjustment of the tuned laser.
  • the phase controller of Figure 1 In order to enable the tuning range of the laser to cover the spacing between the longitudinal modes (often referred to as the fine tuning of the tuned laser), The phase controller of Figure 1 must also be utilized to adjust the position of the longitudinal mode.
  • phase adjusters and mode selection filters can be implemented in different forms, but monolithically integrated tuned lasers typically rely on thermo-optic or electro-optic effects to change the effective refractive index of the mode.
  • DBR Distributed Bragg Reflectot
  • the simplest DBR type tuned laser consists of three parts: the gain zone, the phase zone and the grating zone. Wavelength tuning is achieved by controlling the current in the grating and phase regions.
  • the basic tuning principle is shown in Figure 1.
  • the wavelength tuning range of a conventional DBR tuned laser can only reach 22 nm (Oberg M, Nilsson S, Klinga T, et al.
  • DBR Digital supermode distributed Bragg reflector
  • Ward AJ Robbins DJ
  • Busico G et al. Widely tunable DS-DBR laser with monolithically integrated SOA: Design and performance[J].Selected Topics in Quantum Electronics, IEEE Journal of,2005 11 (1): 149-156
  • Y and modulating the grating arm Modulated grating Y-branch, MGY
  • JO Sarlet G, Hammerfeldt S, et al. State-of-the-art performance of widely tunable modulated grating Y-branch lasers [C]//Optical Fiber Communication Conference.
  • Optical Society of America, 2004: TuE2. Both can achieve a wavelength tuning range of over 40 nm, a side mode rejection ratio of over 35 dB and an output power of over 10 dBm.
  • several other tuned lasers utilize the vernier caliper effect (shown in Figure 2) to achieve wavelength tuning. Two comb-shaped reflection spectra with different wavelength intervals are generated by using two differently structured reflection gratings, and then a wide range of wavelength tuning is achieved by injecting current into the two grating regions by using the vernier effect. The vernier effect allows for large wavelength variations to be obtained with only a small effective refractive index change.
  • the reflection peaks of the two grating alignments determine the lasing wavelength of the laser.
  • the above two types of monolithic integrated tuned lasers use gratings to provide feedback.
  • the precision of grating fabrication is relatively high.
  • electron beam exposure and other fabrication processes are required, and secondary epitaxy is required, thereby increasing the difficulty and cost of laser fabrication.
  • the technical problem to be solved by the present invention is to propose a new large-range tuned laser and its tuning method, which overcomes the defects of high precision and high cost in the prior art commercially available tuned lasers using gratings for mode selection.
  • the present invention proposes a new large-range tuned laser including an optical gain region, a multi-channel branch region, and a multi-channel reflection region; the optical gain region, the multi-channel branch region, and the multi-channel reflection region are Connected from left to right;
  • the optical gain region is configured to provide a gain required for laser lasing; a front end surface of the gain region is an output end surface of the laser;
  • the multi-channel branching area is configured to divide the input light field into a plurality of output light fields
  • the multi-channel reflective area for generating optical feedback and mode selection comprises a plurality of arms of different lengths; the arms are arranged in increasing order of length and the length difference between adjacent arms and arms is not equal; each arm The ends are respectively plated with an anti-reflection film; the plurality of arms of different lengths are respectively provided with independent arm phase regions for independently adjusting the phase of each arm; the number of the plurality of arms of different lengths More than or equal to 3.
  • the wide range tuned laser further includes a common phase region coupled between the optical gain region and the multi-channel branch region for adjusting the wavelength of the longitudinal mode of the laser.
  • the multi-channel branching region is selected by using a multimode interferometer, a Y branch, or a star coupler structure.
  • the wide range tuned laser produces a reflection spectrum having a narrow main reflection peak by interference enhancement of the plurality of different length arms, thereby achieving single mode lasing of the laser.
  • the wide range tuned laser sets a difference in length of adjacent arms of the plurality of different length arms, including the following steps:
  • the half width of the main reflection peak is smaller, which is advantageous for suppressing the longitudinal mode adjacent to the laser, but the suppression effect on other disordered reflection peaks is weak; the average value of ⁇ L i tends to change.
  • the suppression effect on other cluttering reflection peaks becomes stronger, but the half width of the main reflection peak increases, which is not conducive to the suppression of adjacent longitudinal modes;
  • Determining the lengths of the plurality of different length arms including the following steps:
  • the lengths of the arms of the multi-channel reflection zone are respectively set according to the adjacent arm length difference ⁇ L i .
  • a tuning method for the wide-range tuned laser includes the steps of: selecting one arm as a reference arm, adjusting a phase of an arm phase region on the other arm, and aligning phases of the other arms with a reference arm at a certain wavelength
  • the same or phase difference is an integer multiple of 2 ⁇ , thus adjusting the peak wavelength of the main reflection peak, achieving coarse tuning of the laser lasing wavelength.
  • a preferred fine tuning mode is to adjust the phase of the arm phase region of the reference arm and adjust the phase of the arm phase region on the other arms again, so that the phases and phases of the other arms are adjusted.
  • the phase of the reference arm is the same at a certain wavelength or the phase difference is an integral multiple of 2 ⁇ , so that the peak wavelength of the main reflection peak and the longitudinal mode wavelength of the laser are simultaneously adjusted to achieve fine tuning of the laser lasing wavelength.
  • Another preferred method of fine tuning is to further adjust the phase of the common phase region to adjust the longitudinal mode wavelength of the laser to achieve fine tuning of the laser lasing wavelength.
  • the adjustment of the phase of the arm phase region on each arm and the phase of the common phase region is achieved by adjusting the injection current of the corresponding phase region.
  • the present invention does not involve a grating structure, does not require gratings, and the phase on each arm is adjustable, so that it is insensitive to the initial phase on each arm, and is reduced.
  • the accuracy of the arm length is required, so only ordinary lithography is required, which reduces the manufacturing cost of the device.
  • each arm is independent of the loss introduced by the phase region injection current, and the injection current on each arm is not At the same time, it is the largest, so it can effectively reduce the influence of the loss caused by the injection current on the reflection spectrum.
  • the tunable laser of the present invention requires only a phase shift of ⁇ at most on each arm for wavelength tuning, while the length of the arm phase region on each arm can be long, thus reducing the arm phase on the arm.
  • the region has the requirement of phase shifting capability; in addition, the relatively long arm phase region can reduce the density of the injection current and reduce the thermal effect caused by the injection current, thereby facilitating the speed of wavelength tuning.
  • the reflective structure of the present invention is on the right side of the optical gain region, and the light is output from the left side of the optical gain region, so the output is not subject to the injection current.
  • the effect of the induced absorption allows the output optical power to be tuned with wavelength to be stable over a wide range of wavelength variations, thereby reducing the difficulty of control.
  • Figure 1 shows the basic structure and operation of a tuned laser.
  • Figure 2 is a schematic illustration of the vernier caliper effect.
  • FIG 3 is a schematic structural view of a tuned laser based on multi-channel interference.
  • Figure 4 is a reflection spectrum when the length differences of adjacent arms are equal.
  • Fig. 5 shows the case of eight arms when ⁇ L i is not equal, and the average value of ⁇ L i of (a) is larger than that of (b).
  • Figure 6 is a schematic diagram showing the structure of a tuned laser based on eight-channel interference.
  • Figure 7 is a longitudinal cross-sectional view of a tuned laser based on eight-channel interference.
  • Figure 8 is a reflection spectrum corresponding to different lasing wavelengths.
  • Figure 9(a) shows the lasing spectrum of the tuned laser based on eight-channel interference at different wavelengths, (b) the edge-sensing ratio of the different lasing wavelengths, and (c) the threshold current.
  • Fig. 10 is an L-I graph corresponding to a wavelength of 1550 nm, wherein the inset is an enlarged view near the threshold.
  • the multi-channel interference based tuning laser scheme of the present invention is shown in FIG. It comprises four parts: an optical gain zone 1, a common phase zone 2, a multi-channel branching zone 3, and a multi-channel reflection zone 4.
  • the common phase zone 2 is between the optical gain zone 1 and the multi-channel branch zone 3;
  • the multi-channel branch zone 3 is between the common phase zone 2 and the multi-channel reflection zone 4.
  • the optical gain zone 1 is used to provide the gain required for laser lasing;
  • the common phase zone 2 is used to adjust the wavelength of the laser longitudinal mode;
  • the multi-channel branch zone 3 can be multimode interferometer (MMI), Y-branch (Y- A branch, or a star coupler, is used to divide the input light field into multiple output light fields.
  • MMI multimode interferometer
  • Y-branch Y- A branch
  • star coupler is used to divide the input light field into multiple output light fields.
  • the multi-channel reflection zone 4 is composed of a plurality of arms of different lengths, each arm is designed with a separate arm phase zone 5, and the end of each arm is usually plated with an anti-reflection film 6; the arm phase zone 5 is used to adjust each The phase on the arm.
  • the front end face of the optical gain zone 1 is the output end face 7 of the laser.
  • the principle of the multi-channel interference tuned laser of the present invention is as follows:
  • the total complex reflection coefficient at the right end of the optical gain region is the total complex reflection coefficient at the right end of the optical gain region.
  • N is the number of channels
  • ⁇ is the wavelength
  • j is the imaginary unit
  • r 3 is the reflection coefficient at the end of each arm (the reflection coefficient at the end of each arm is the same)
  • L p is the length of the common phase region
  • L m is the propagation length of the multi-channel branch region
  • ⁇ is the intrinsic loss of the passive waveguide and ⁇ is the propagation constant of the waveguide mode.
  • ⁇ is the intrinsic loss of the passive waveguide and ⁇ is the propagation constant of the waveguide mode.
  • the multi-channel branching region divides the input light into N-parts of equal power, but in practice this is not necessary, for example, if a star coupler is used to achieve this In the channel branch area, the power of the output light will be distributed in a plurality of channels in accordance with a Gaussian function.
  • the back and forth phase from the right end of the optical gain region to the end of each arm should be the same at the wavelength ⁇ 0 , so that the reflection of each arm is The wavelength ⁇ 0 is interference enhanced.
  • the same phase on each arm means that the phase difference between the arms and the arms is an integer multiple of 2 ⁇ .
  • each phase arm of the wavelength [lambda] 0 can be enhanced to produce a strong reflection peak at 0 interferometric wavelength ⁇ , but the entire shape of the reflection spectrum, especially the inhibition of other relatively weak reflection peak is adjacent arms
  • the difference in length is determined. Assuming that the lengths of the arms are arranged in ascending order, ⁇ L i is the difference in length between the i-th arm and the i+1th arm, then:
  • a comb-like reflection spectrum having a plurality of reflection peaks is not required, but a reflection spectrum containing only one main reflection peak is required to ensure that the laser achieves single-mode lasing.
  • ⁇ L i is not equal, the periodicity of the reflection spectrum is destroyed, resulting in a reflection spectrum with many cluttered reflection peaks.
  • the phase is controlled by the arm phase region 5 on each arm such that the phase on each arm is in phase at the wavelength ⁇ 0 , then the interference enhancement at wavelength ⁇ 0 produces a primary reflection peak.
  • the arm lengths of all the arms are determined.
  • the difference between the lengths of the other N-1 arms and the first arm is
  • the multi-channel interference tuned laser of the present invention utilizes a plurality of different lengths.
  • the interference enhancement of the arms produces a reflection spectrum with a narrow main reflection peak, thereby achieving single mode lasing.
  • the peak wavelength of the main reflection peak can be adjusted by adjusting the phase of the arm phase region on the N-1 arms, thereby achieving coarse adjustment of the laser.
  • the fine adjustment after coarse adjustment is to achieve fine tuning of the lasing wavelength by changing the position of the longitudinal mode of the laser covered by the main reflection peak.
  • Fine tuning can be achieved in two ways.
  • the first is to fine-tune the position of the longitudinal mode by adjusting the phase of the common phase zone 2, which is the same as the conventional DBR-type tuned laser.
  • the second is by adjusting the phase on the first arm.
  • the length of the first arm is actually a part of the entire length of the cavity, and the phase of its adjustment has the same effect as the phase of the common phase zone 2.
  • the difference is that when the phase of the first arm is adjusted, the other N-1 arms are also adjusted to maintain the phase. It is foreseeable that this tuning method will make the control of the entire laser more complicated.
  • N+1 phase regions N arm phase regions 5 plus a common phase region 2
  • the present invention designs a specific implementation example of a tuned laser based on eight-channel interference and simulates it.
  • FIG. 6 A schematic diagram of the eight-channel interference tuned laser is shown in Fig. 6. It consists of four parts: optical gain area 1, common phase area 2, 1x8 branch area 3, and octal reflection area 4; 1x8 branch area 3 consists of 1x2 MMI8 Cascade composition, 1x2 MMI8 output waveguide and input waveguide are connected by S-shaped waveguide 9; eight-channel reflection zone 4 is composed of 8 arms of different lengths, ⁇ L i is different, and each arm is designed with an independent arm phase District 5.
  • a 2 um wide deep etched ridge waveguide structure is used.
  • the optical gain region 1 is 400 ⁇ m long and contains five layers of compressively strained InGaAsP quantum wells with a peak at 1550 nm.
  • the optical gain region 1 includes an electrode contact layer 10, a capping layer 11, an upper confinement layer 12, an active layer 13 and a lower confinement layer 14 from top to bottom; the common phase region 2 and the phase region 5 on each arm are 100 ⁇ m in length, From top to bottom, the electrode contact layer 10, the cap layer 11, the upper confinement layer 12, the optical waveguide layer 15 and the lower confinement layer 14; the Mx branch region of 1x8 is composed of a 1x2 MMI cascade, and the width of the 1x2 MMI is 8 ⁇ m, and the length is 69 ⁇ m, the 1x2 MMI between the stages is connected by S-waveguides, the radius of the S-waveguide is 100 ⁇ m; the spacing between the eight channel arms and the arms is 20 ⁇ m.
  • the length of each arm is
  • the unit is ⁇ m; the 1x8 branching zone 3 and the non-phase region on each arm include the capping layer 11, the upper confinement layer 12, the optical waveguide layer 15 and the lower limit layer 14 from top to bottom; the natural cleavage plane of the front end face of the laser 7 reflectance is 0.32, the reflectivity of the last eight metal plated antireflection film 6 is 0.81; the electrode 16 is formed on the optical gain zone 1, the common phase zone 2 and the phase zone 5 on the eight arms; the laser is from the front end face Output.
  • the tuning method uses the adjustment of the arm phase zone 5 on the eight arms simultaneously.
  • the lasing spectrum, side mode suppression ratio, threshold current and L-I curve of the laser are obtained by solving the multimode rate equation.
  • Figure 9(a) shows the lasing spectra corresponding to different lasing wavelengths.
  • the output power is greater than 13dBm. It can be seen from the results that the output power varies very little in the tuning range of 40 nm, in the range of 0.3 dB.
  • Figure 9(b) shows the side mode rejection ratio for different lasing wavelengths, with a side mode rejection ratio of up to 51.4 dB over a 40 nm tuning range.
  • Figure 9(c) shows the threshold currents for different lasing wavelengths. It can be seen that the threshold of the laser is around 10 mA.
  • the corresponding L-I curve of the lasing wavelength at 1550 nm is shown in FIG.
  • the threshold current is 9.2 mA and the slope efficiency is 0.24 mW/mA.
  • the present invention first proposed a large-range tuned laser based on multi-channel interference.
  • the laser is wavelength selective based on the interference of multiple arms of different lengths.
  • a very narrow main reflection peak can be obtained at the wavelength ⁇ 0 ;
  • the phase is such that it satisfies the phase condition of the wavelength ⁇ 1 interference enhancement, and the main reflection peak can be shifted from the wavelength ⁇ 0 to the wavelength ⁇ 1 .
  • the octave-based tuned laser has a tuning range of over 40 nm, a side mode rejection ratio of up to 51 dB, a threshold current as low as 10 mA, and an output power exceeding the tuning range. 13dBm, and has good uniformity, which proves that the wide-range tuned laser based on multi-channel interference proposed by the present invention is feasible, and good tuning performance can be obtained by reasonable design.
  • the 8-channel interference large-range tuned laser provided by the specific embodiment is merely an example, and does not constitute a specific limitation on whether the number of channels or the number of channels constitutes a parity number. .

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Abstract

一种大范围波长可调谐激光器及其调谐方法，涉及大范围波长可调谐激光器技术领域，调谐激光器包含光增益区（1），公共相位区（2），多通道分支区（3）以及多通道反射区（4）。多通道分支区（3）将输入通道分成多个输出通道。多通道反射区（4）包含若干个长度不同的臂，每个臂上有一个独立的臂相位控制区（5）；相邻臂的长度差不相等，以使得多通道反射区（4）干涉产生单个反射峰占主导的反射谱，反射谱保证了激光器的单模工作。通过结合调节公共相位区（2）的相位以及多通道反射区（4）每个臂上的相位，能够实现激光器的波长大范围精细调谐。可调谐激光器具有制作难度小，成本低，调谐范围广，调谐效果好，调谐控制方便的优点。

Description

一种大范围调谐激光器及其调谐方法 技术领域
本发明涉及大范围波长可调谐激光器技术领域，涉及的是一种大范围波长可调谐激光器及其调谐方法。
背景技术
随着长距离、大容量、超高速光纤通信技术的发展，半导体调谐激光器成长为光纤通信系统和下一代光网络的关键器件之一。在密集波分复用(DWDM)系统中，调谐激光器能够代替多个波长固定的激光器，这样不仅能够极大地降低备用光源的成本，还能够提供及时有效的库存管理和信道快速建立功能。在下一代可重构光网络中，调谐激光器还能够提供自动波长配置、波长转换以及波长路由功能，从而增加网络的灵活性和宽带利用率。近几十年，调谐激光器受到国内外的广泛关注和研究。
调谐激光器的基本结构和工作原理如图1所示。调谐激光器可以由最基本的Fabry-Pérot(F-P)腔激光器，相位控制器以及模式选择滤波器构成。F-P腔激光器仅由增益介质和谐振腔(由两端面反射镜构成)组成，满足激光器工作条件的波长(激光器的纵模)有很多个。由于半导体增益介质的增益谱通常都比较平坦，如图1中的增益谱所示，所以普通的F-P腔激光器不具有选模机制，一般是多模激射的。为了实现单纵模激射，需要模式选择滤波器将单个纵模选出来。通常滤波器的中心波长要靠近所要选择的模式，这样该模式由滤波器所引起的额外损耗要小于其他模式，从而在激光器的激射谱中占主导地位。该模式输出功率与其他模式输出功率的比通常称为边摸抑制比(Side Mode Suppression Ratio，SMSR)。通过调节滤波器的中心波长就可以选择不同的纵模来激射，这种调节通常称为调谐激光器的粗调。为了使得激光器的调谐范围能够覆盖纵模之间的间隔(通常称为调谐激光器的细调)， 图1中的相位控制器还必须被利用起来调节纵模的位置。实际设计中，相位调节器和模式选择滤波器可以通过不同的形式来实现，但单片集成的调谐激光器通常都依赖热光或电光效应来改变模式的有效折射率。
目前调谐激光器正向着大调谐范围、高边模抑制比、高输出功率、高波长切换速度、窄线宽，以及单片集成等方向发展。许多研究机构和商业公司提出了多种调谐激光器方案。目前商业可用的单片集成的大范围波长调谐激光器方案主要有两种：一种是通过温度调谐(热光效应)的分布反馈(Distributed Feedback，DFB)激光器阵列(Zah C E，Favire F J，Pathak B，et al.Monolithic integration of multiwavelength compressive-strained multiquantum-well distributed-feedback laser array with star coupler and optical amplifiers[J].Electronics Letters，1992，28(25)：2361-2362.)；另一种是利用注入电流产生的电光效应进行调谐的分布反射(Distributed Bragg Reflectot，DBR)型调谐激光器。DFB激光器阵列是在单个DFB激光器的基础上发展起来的。通过温度进行调谐，单个DFB激光器的调谐范围一般只有3到5nm。因此将多个具有不同中心波长的DFB激光器以并联的方式集成起来，就可以实现大范围的波长调谐。
最简单的DBR型调谐激光器由三部分组成：增益区，相位区和光栅区。通过控制光栅区和相位区的电流实现波长调谐，其基本调谐原理如图1所示。但是普通的DBR型调谐激光器的波长调谐范围最大只能达到22nm(Oberg M，Nilsson S，Klinga T，et al.A three-electrode distributed Bragg reflectot laser with 22nm wavelength tuning range[J].Photonics Technology Letters，IEEE，1991，3(4)：299-301.)，不足以覆盖整个C波段。为了增大DBR型可调激光器的波长调谐范围，近二十年提出了许多改进的波长调谐方案，如取样光栅分布反射(Sample grating distributed Bragg reflector，SGDBR)调谐激光器(Jayaraman V，Chuang Z M，Coldren L A.Theory，design，and performance of extended tuning range semiconductor  lasers with sampled gratings[J].Quantum Electronics，IEEE Journal of，1993，29(6)：1824-1834.)，超结构光栅分布反射(Super-structure grating distributed Bragg reflector，SSGDBR)调谐激光器(Ishii H，Tanobe H，Kano F，et al.Quasicontinuous wavelength tuning in super-structure-grating(SSG)DBR lasers[J].Quantum Electronics，IEEE Journal of，1996，32(3)：433-441.)，数字超模分布反射(Digitalsupermode distributed Bragg reflector，DSDBR)调谐激光器(Ward A J，Robbins D J，Busico G，et al.Widely tunable DS-DBR laser with monolithically integrated SOA：design and performance[J].Selected Topics in Quantum Electronics，IEEE Journal of，2005，11(1)：149-156.)，以及调制光栅Y臂(Modulated grating Y-branch，MGY)调谐激光器(
Figure PCTCN2015082342-appb-000001
J O，Sarlet G，Hammerfeldt S，et al.State-of-the-art performance of widely tunable modulated grating Y-branch lasers[C]//Optical Fiber Communication Conference.Optical Society of America，2004：TuE2.)，它们都能够实现超过40nm的波长调谐范围，超过35dB的边模抑制比以及超过10dBm的输出功率。除了DS-DBR激光器以外，其它几种调谐激光器都是利用的游标卡尺效应(如图2所示)来实现波长调谐的。通过使用两个不同结构的反射光栅产生两个具有不同波长间隔的梳状反射谱，然后利用游标效应，通过对两个光栅区注入电流的方式来实现大范围的波长调谐。游标效应使得只需要很小的有效折射率变化就可以获得很大的波长变化。如图2所示，两个光栅对准的反射峰决定了激光器的激射波长。以上两类单片集成调谐激光器都是利用光栅提供反馈，然而制作光栅的精度要求比较高，通常需要电子束曝光等制作工艺，同时需要二次外延，因此增加了激光器的制作难度和成本。
发明内容
本发明所要解决的技术问题是提出一种新的大范围调谐激光器及其调谐方法，克服现有常见的商业可用的调谐激光器利用光栅进行选模所存在的制作精度要求高和成本高的缺陷。
为解决上述技术问题，本发明提出了一种新的大范围调谐激光器，包括光增益区、多通道分支区以及多通道反射区；所述光增益区、多通道分支区以及多通道反射区从左到右顺序连接；
所述光增益区，用于提供激光器激射所需的增益；增益区前端面为激光器的输出端面；
所述多通道分支区，用于将输入光场分成若干个输出光场；
所述多通道反射区，用于产生光反馈和模式选择；它包括若干个不同长度的臂；将这些臂按长度递增顺序排列则相邻臂与臂之间的长度差不相等；每个臂的末端分别镀有增反膜；所述若干个不同长度的臂上分别设有独立的臂相位区，这些臂相位区用于独立调节每个臂的相位；所述若干个不同长度臂的数量大于等于3个。
所述大范围调谐激光器，还包括公共相位区，所述公共相位区连接在所述光增益区与所述多通道分支区之间，用于调节激光器纵模的波长。
所述多通道分支区选择采用多模干涉器，Y分支，或者星形耦合器结构实现。
所述大范围调谐激光器，通过所述若干个不同长度臂的干涉增强产生一个具有窄的主反射峰的反射谱，从而实现激光器的单模激射。
所述大范围调谐激光器设定所述若干个不同长度臂的相邻臂的长度差，包括以下步骤：
尝试调整各相邻臂之间的长度差ΔLi；
ΔLi的平均值趋于变大时，主反射峰半宽较小因而有利于抑制激光器相邻的纵模，但是对其它杂乱的反射峰抑制效果会变弱；ΔLi的平均值趋于变小时，对其它杂乱的反射峰抑制效果会变强，但是主反射峰半宽增大因而 不利于相邻纵模的抑制；
通过优化得到的理想的相邻臂的长度差ΔLi，采用该长度差ΔLi确定各臂的长度，对激光器相邻的纵模以及其他杂乱的反射峰同时具有合适的抑制。
确定所述若干个不同长度臂的长度，包括以下步骤：
先设定各个臂中某一臂的长度；
根据所述的相邻臂长度差ΔLi，分别设定所述多通道反射区的各个臂的长度。
一种所述大范围调谐激光器的调谐方法，包括以下步骤：选择某一臂为参考臂，调节其他臂上的臂相位区的相位，使其他各个臂的相位与参考臂在某一波长处相位相同或相位差为2π的整数倍，这样就调节了主反射峰的峰值波长，实现了所述激光器激射波长的粗调谐。
优选的，一种优选的精细调谐方式是，调节所述参考臂的臂相位区的相位，并再次调节其他臂上的臂相位区的相位，使其他各个臂的相位与相位调整后的所述参考臂的相位在某一波长处相同或相位差为2π的整数倍，这样同时调节主反射峰的峰值波长以及激光器的纵模波长，实现激光器激射波长的精细调谐。
另一种优选的精细调谐方式是，进一步调节公共相位区的相位以调节激光器的纵模波长，实现激光器激射波长的精细调谐。
所述调节每个臂上的臂相位区的相位以及公共相位区的相位，是通过调节相应相位区的注入电流实现的。
相较于其它商业可用的大范围调谐激光器，本发明提出的调谐激光器具有以下优点：
1、与DFB阵列激光器和DBR型调谐激光器相比，本发明不涉及光栅结构，不需要制作光栅，同时每个臂上的相位可调，因此对每个臂上的初始相位不敏感，降低了对臂长度的制作精度的要求，所以只需要普通光刻，降低了器件制作成本。
2、反射谱是由各臂的反射叠加而成的，而不是利用光栅实现，因此每个臂受到相位区注入电流引入的损耗的影响是相互独立的，另外每个臂上的注入电流并不是同时最大的，因此能够有效地降低由注入电流引起的损耗对反射谱的影响。
3、本发明的可调谐激光器在进行波长调谐时每个臂上最大只需要产生π的相移，同时每个臂上的臂相位区的长度可以很长，因此降低了对臂上的臂相位区产生相移能力的要求；另外使用相对较长的臂相位区能够降低注入电流的密度，减小注入电流引起的热效应，从而有利于提高波长调谐的速度。
4、与调制光栅Y分支分布式布拉格反射(MGY-DBR)激光器类似，本发明的反射结构都在光增益区的右侧，光从光增益区的左侧输出，因此输出不会受注入电流引起的吸收的影响，使得输出光功率随波长调谐能够在较大波长变化范围内保持稳定，从而降低了控制的难度。
附图说明
下面结合附图和具体实施方式对本发明的技术方案作进一步具体说明。
图1为调谐激光器的基本结构和工作原理。
图2为游标卡尺效应说明示意图。
图3为基于多通道干涉的调谐激光器的结构示意图。
图4为相邻臂的长度差相等时候的反射谱。
图5为ΔLi不相等时候8个臂的情况，(a)的ΔLi的平均值比(b)的大。
图6为基于八通道干涉的调谐激光器结构示意图。
图7为基于八通道干涉的调谐激光器的纵截面图。
图8为不同激射波长对应的反射谱。
图9(a)为模拟得到的基于八通道干涉的调谐激光器在不同波长的激射谱，(b)为不同激射波长对应的边摸抑制比曲线图，(c)为阈值电流 随波长变化的曲线图。
图10为1550nm波长对应的L-I曲线图，其中插图是阈值附近的放大图。
具体实施方式
本发明的基于多通道干涉的调谐激光器方案如图3所示。它包括4个部分：光增益区1、公共相位区2、多通道分支区3以及多通道反射区4。公共相位区2在光增益区1和多通道分支区3之间；多通道分支区3在公共相位区2和多通道反射区4之间。光增益区1用于提供激光激射所需的增益；公共相位区2用于调节激光器纵模的波长；多通道分支区3可由多模干涉器(Multimode Interferometer，MMI)，Y分支(Y-branch)，或者星形耦合器(Star Coupler)等结构组成，用于将输入光场分成多个输出光场。多通道反射区4由多个不同长度的臂组成，每个臂上设计有一个独立的臂相位区5，且每个臂的末端通常镀有增反膜6；臂相位区5用于调节每个臂上的相位。光增益区1前端面为激光器的输出端面7。
本发明的多通道干涉调谐激光器的原理如下：
光增益区右端总的复反射系数为
Figure PCTCN2015082342-appb-000002
其中，N为通道数目，λ为波长，j为虚数单位，r3是每个臂末端的反射系数(设每个臂末端的反射系数是相同的)，Lp是公共相位区的长度，Lm是多通道分支区的传播长度，Li(i＝1，2，3…N)是第i个臂的长度，
Figure PCTCN2015082342-appb-000003
是传播模式的复传播常数，
Figure PCTCN2015082342-appb-000004
其中α是无源波导的本征损耗，β是波导模式的传播常数。为简单分析起见，在(1)式中假设了多通道分支区将输入光分成了功率相等的N 份光场，但实际中这个并不是必须的，比如如果采用星形耦合器来实现这个多通道分支区的话，输出光的功率在多个通道中将是按照高斯函数来分布的。为了使反射谱在指定的波长λ0处干涉增强产生一个非常强的反射峰，那么从光增益区右端到每个臂末端的来回相位在波长λ0处应该相同，这样每个臂的反射在波长λ0处是干涉增强的。每个臂上同相位意味着臂与臂之间的相位差为2π的整数倍。
虽然使每个臂在波长λ0处同相位就能够在波长λ0处干涉增强产生一个强反射峰，但是整个反射谱的形状尤其是对其他相对较弱的反射峰的抑制是由相邻臂的长度差决定的。假设臂的长度按递增顺序排列，ΔLi为第i个臂和第i+1个臂的长度差，则有：
ΔLi＝Li+1-Li，i＝1，2，3...N-1   (3)
这样(1)式可由ΔLi表达出来：
Figure PCTCN2015082342-appb-000005
从(4)式可以看出，公共相位区、多通道分支区以及第一个臂的长度反应出来只是腔长的一部分，这个体现在因子
Figure PCTCN2015082342-appb-000006
中；相邻臂的长度差ΔLi决定了整个反射谱的形状，所以可以通过优化ΔLi来优化整个反射谱。最简单的，如果ΔLi相等，就会干涉叠加得到一个梳状反射谱，且梳状反射谱的反射峰的半宽以及自由频谱范围(Free Spectral Range，FSR)和ΔLi的大小相关。图4(a)和4(b)展示了8个具有等长度差的臂的反射谱，从图中可以看出ΔLi越大，梳状反射谱的反射峰就越窄，同时梳状反射谱的FSR越小。但是对于本激光器而言，不需要具有多个反射峰的梳状反射谱，而是需要只包含一个主反射峰的反射谱以保证激光器实现单模激射。如果ΔLi不相等，反射谱的周期性就会被破坏，从而得到一个具有许多杂乱反射峰的反射谱。如前面所述的，通过每个臂上的臂相位区5来控制相位，使每个臂上的相位在波长λ0处都同相位，那么就会在波长λ0处干涉 增强产生一个主反射峰。图5(a)和图5(b)展示了两组ΔLi不相等时八个臂的反射谱，从图中可以看出除了在λ0＝1530nm处产生了一个非常强的主反射峰，还有很多杂乱的反射峰。要使激光器具有良好的单模特性，反射谱的主反射峰的半宽应该比较小因而能够抑制相邻的纵模，同时其它杂乱的反射峰也能够被很好的抑制。在优化ΔLi时，发现如果ΔLi平均比较大，主反射峰半宽会比较小因而有利于抑制相邻的纵模，但是对其它杂乱的反射峰抑制效果会变弱，如图5(a)所示。相反，如果ΔLi平均比较小，对其它杂乱的反射峰抑制效果会变强，但是主反射峰半宽会增大因而不利于相邻纵模的抑制，如图5(b)所示。
通过优化确定了ΔLi的长度得到了理想的反射谱之后，那么所有臂的臂长就确定了。其它N-1个臂与第一个臂的长度差为
Li+1-L1＝ΔL1+ΔL2+…+ΔLi，i＝1，2，3...N-1   (5)
对应的初始往返相位差为
Figure PCTCN2015082342-appb-000007
由于制作精度的问题，激光器不大可能在初始状态下就满足Δφi(λ0)在波长λ0处等于2π的整数倍，实际中总会有初始相位误差，在式(6)中我们用
Figure PCTCN2015082342-appb-000008
表示。由于每个臂上都有一个独立的臂相位区5，通过向每个臂上独立的臂相位区5独立注入电流来改变相位，将第2到第N个臂上的初始相位
Figure PCTCN2015082342-appb-000009
都抵消掉，这样就可以使第2到第N个臂和第一个臂同相位，从而在波长λ0处干涉增强产生一个窄的主反射峰，实现波长λ0附近的纵模激射。如果我们要使波长λ1附近的纵模激射，就必须重新调整每个臂上的相位，使其在波长λ1处同相位，这样窄的主反射峰就会从波长λ0处移到波长λ1处，从而实现激射波长从λ0附近的纵模向λ1附近的纵模的调谐。因此对于本激光器而言，窄的主反射峰的产生和波长的粗调谐都是通过控制第2到N个臂上的相位来实现。
经过上述，可知本发明的多通道干涉调谐激光器是利用多个不同长度 臂的干涉增强产生一个具有窄的主反射峰的反射谱，从而实现单模激射。通过调节N-1个臂上的臂相位区的相位可以调节主反射峰的峰值波长，从而实现激光器的粗调。
粗调之后的细调，则是需要通过改变主反射峰所覆盖的激光器纵模的位置，从而实现激射波长的精细调谐。
细调有两种方法可以实现，第一种是通过调整公共相位区2的相位来调节纵模的位置实现细调，这和传统的DBR类调谐激光器相同。第二种是通过调节第一臂上的相位。如公式(4)所示，第一臂的长度实际是整个腔长的一部分，调整它的相位具有和调整公共相位区2的相位相同的效果。但有一点不同的是，当第一个臂的相位被调整以后，其他N-1个臂也要做相应的调整以保持相位一致。可以预见这种调谐方式将会使得整个激光器的控制变得更复杂一些。综上所述，虽然在图3中，我们一共设计了N+1个相位区(N个臂相位区5加一个公共相位区2)，但实际中只需要控制N个相位区就可以实现激光器激射波长的粗调和细调。
为进一步说明本发明的可行性，本发明设计了一个基于八通道干涉的调谐激光器的具体实施例子，并对其进行了模拟仿真。
该八通道干涉的调谐激光器的示意图如图6所示，它由四个部分组成：光增益区1，公共相位区2，1x8分支区3以及八通道反射区4；1x8分支区3由1x2 MMI8级联组成，1x2 MMI8输出波导和输入波导间由S型波导9连接；八通道反射区4由8个具有不同长度的臂组成，ΔLi不相同，每个臂上设计有一个独立的臂相位区5。在无源区域激光器采用的是2um宽的深刻蚀脊波导结构。光增益区1长400μm，包含5层峰值在1550nm的压应变InGaAsP量子阱。光增益区1从上而下包括电极接触层10、盖帽层11、上限制层12、有源层13和下限制层14；公共相位区2和每个臂上的相位区5长度为100μm，从上而下含电极接触层10、盖帽层11、上限制层12、光波导层15和下限制层14；1x8的MMI分支区由1x2 MMI级 联组成，1x2 MMI的宽为8μm，长为69μm，各级间的1x2 MMI由S波导连接，S波导的半径为100μm；8个通道臂与臂之间的间距是20μm。每个臂的长度分别为
L1 L2 L3 L4 L5 L6 L7 L8
100.00 109.94 253.91 299.13 318.08 350.99 376.56 512.71
单位为μm；1x8分支区3和每个臂上非相位区域从上而下包含盖帽层11、上限制层12、光波导层15和下限值层14；激光器的前端面的自然解理面7反射率为0.32，后八个镀了金属增反膜6的反射率为0.81；光增益区1、公共相位区2和八个臂上的相位区5上均制作有电极16；激光从前端面输出。
调谐方式采用的是同时调节八个臂上的臂相位区5。通过求解多模速率方程得到该激光器的激射谱、边模抑制比、阈值电流以及L-I曲线等结果。
表一、八通道干涉调谐激光器模拟所用参数
有源区体积V(μm3) 26
有源区长度La(μm) 400
波导宽度(μm) 2
MMI长度LMMI(μm) 69
MMI宽度dMMI(μm) 8
MMI分支区传播长度(μm) 474.59
S波导半径(μm) 100
S波导分离距离(μm) 80，40，20
相位控制区长度(μm) 100
前反射面发射率R1 0.32
后反射面反射率R2 0.81
光限制因子(％) 5
群折射率ng 3.6
有源区损耗(cm-1) 20
无源区损耗(cm-1) 5
线性复合系数A(108s-1) 1
辐射复合系数B(10-10cm3s-1) 1
俄歇复合系数C(10-29cm6s-1) 3.5
自发辐射因子(10-5) 2.5
注入电流I(mA) 150
真空中的光速(108m/s) 3
纵模间距(nm) 0.24
图9(a)显示了不同激射波长对应的激射谱。输出功率大于13dBm。从结果中可以看出输出功率在40nm的调谐范围变化非常小，在0.3dB范围内。图9(b)显示了不同激射波长对应的边模抑制比，在40nm的调谐范围内，边模抑制比高达51.4dB。图9(c)显示了不同激射波长对应的阈值电流，可以看出激光器的阈值在10mA左右。
激射波长在1550nm时对应的L-I曲线如图10所示。阈值电流在9.2mA，斜率效率是0.24mW/mA。
综上，本发明第一次提出了基于多通道干涉的大范围调谐激光器。激光器是基于多个具有不同长度的臂的干涉实现波长选择的。通过调节每个臂上的相位，使每个臂上的相位满足指定波长λ0干涉增强的相位条件，可以在波长λ0处得到一个非常窄的主反射峰；同样只需调节每个臂上的相位使其满足波长λ1干涉增强的相位条件，就可以将主反射峰从波长λ0处移到波长λ1。通过基于八通道的调谐激光器的模拟结果，该基于八通道干涉的调谐激光器具有超过40nm的调谐范围，高达51dB的边模抑制比，低至10mA左右的阈值电流，同时在调谐范围内输出功率超过13dBm，且具有很好的均匀性，证明了本发明提出的基于多通道干涉的大范围调谐激光器是可行的，并且通过合理的设计能够获得很好的调谐性能。
基于上述本发明的设计原理，本领域技术人员完全能够理解，本具体实施例所提供的8通道干涉的大范围调谐激光器仅仅只是举例，并非构成对通道数量或通道数是否构成奇偶数的具体限定。
最后所应说明的是，以上具体实施方式仅用以说明本发明的技术方案 而非限制，尽管参照较佳实施例对本发明进行了详细说明，本领域的普通技术人员应当理解，可以对本发明的技术方案进行修改或者等同替换，而不脱离本发明技术方案的精神和范围，其均应涵盖在本发明的权利要求范围当中。

Claims (10)

  1. 一种大范围调谐激光器，其特征在于，包括光增益区、多通道分支区以及多通道反射区；所述光增益区、多通道分支区以及多通道反射区从左到右顺序连接；
    所述光增益区，用于提供激光器激射所需的增益；增益区前端面为激光器的输出端面；
    所述多通道分支区，用于将输入光场分成若干个输出光场；
    所述多通道反射区，用于产生光反馈和模式选择；它包括若干个不同长度的臂；将这些臂按长度递增顺序排列则相邻臂与臂之间的长度差不相等；每个臂的末端分别镀有增反膜；所述若干个不同长度的臂上分别设有独立的臂相位区，这些臂相位区用于独立调节每个臂的相位；所述若干个不同长度臂的数量大于等于3个。
  2. 根据权利要求1所述的大范围调谐激光器，其特征在于，还包括公共相位区，所述公共相位区连接在所述光增益区与所述多通道分支区之间，用于调节激光器纵模的波长。
  3. 根据权利要求1所述的大范围调谐激光器，其特征在于，多通道分支区选择采用多模干涉器，Y分支，或者星形耦合器结构实现。
  4. 根据权利要求1至3之一所述的大范围调谐激光器，其特征在于，利用所述若干个不同长度臂的干涉增强产生一个具有窄的主反射峰的反射谱，从而实现激光器的单模激射。
  5. 根据权利要求4所述的大范围调谐激光器，其特征在于，设定所述若干个不同长度臂的相邻臂的长度差，包括以下步骤：
    尝试调整各相邻臂之间的长度差ΔLi；
    ΔLi的平均值趋于变大时，主反射峰半宽较小因而有利于抑制激光器相邻的纵模，但是对其它杂乱的反射峰抑制效果会变弱；ΔLi的平均值趋于变 小时，对其它杂乱的反射峰抑制效果会变强，但是主反射峰半宽增大因而不利于相邻纵模的抑制；
    通过优化得到的理想的相邻臂的长度差ΔLi，采用该长度差ΔLi确定各臂的长度，对激光器相邻的纵模以及其他杂乱的反射峰同时具有合适的抑制。
  6. 根据权利要求5给所述的大范围调谐激光器，其特征在于，确定所述若干个不同长度臂的长度，包括以下步骤：
    先设定各个臂中某一臂的长度；
    根据所述的相邻臂长度差ΔLi，分别设定所述多通道反射区的各个臂的长度。
  7. 一种权利要求6所述的大范围调谐激光器的调谐方法，其特征在于，包括以下步骤：选择某一臂为参考臂，调节其他臂上的臂相位区的相位，使其他各个臂的相位与参考臂在某一波长处相位相同或相位差为2π的整数倍，这样就调节了主反射峰的峰值波长，实现了所述激光器激射波长的粗调谐。
  8. 根据权利要求7所述的大范围调谐激光器的调谐方法，其特征在于，包括以下步骤：调节所述参考臂的臂相位区的相位，并再次调节其他臂上的臂相位区的相位，使其他各个臂的相位与相位调整后的所述参考臂的相位在某一波长处相同或相位差为2π的整数倍，这样同时调节主反射峰的峰值波长以及激光器的纵模波长，实现激光器激射波长的精细调谐。
  9. 根据权利要求7所述的大范围调谐激光器的调谐方法，其特征在于，还包括以下步骤：调节公共相位区的相位以调节激光器的纵模波长，实现激光器激射波长的精细调谐。
  10. 根据权利要求7、8、9之一所述的大范围调谐激光器的调谐方法，其特征在于，所述调节每个臂上的臂相位区的相位以及公共相位区的相位，是通过调节相应相位区的注入电流实现的。
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CN104393484B (zh) * 2014-11-27 2018-05-29 华中科技大学 一种大范围调谐激光器及其调谐方法
CN106785885B (zh) * 2016-11-21 2020-11-24 华中科技大学 一种多通道干涉激光器与半导体光放大器的集成器件
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CN114034468B (zh) * 2021-11-04 2023-10-17 宁波元芯光电子科技有限公司 一种多通道干涉激光器的波长标定方法
WO2023223450A1 (ja) * 2022-05-18 2023-11-23 日本電信電話株式会社 半導体光集積デバイス

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102282458A (zh) * 2009-03-12 2011-12-14 特拉维夫大学未来技术发展有限合伙公司 发光腔内干涉传感器
US20120057079A1 (en) * 2009-10-13 2012-03-08 Skorpios Technolgies, Inc. Method and system for hybrid integration of a tunable laser for a cable tv transmitter
CN102646927A (zh) * 2012-04-11 2012-08-22 四川马尔斯科技有限责任公司 基于波导反射光栅阵列的波长可调谐外腔激光器
CN103457155A (zh) * 2013-07-26 2013-12-18 李若林 混合集成复合腔波长可调谐激光发射器
CN104393484A (zh) * 2014-11-27 2015-03-04 华中科技大学 一种大范围调谐激光器及其调谐方法

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5457760A (en) * 1994-05-06 1995-10-10 At&T Ipm Corp. Wavelength division optical multiplexing elements
US6614951B2 (en) * 2001-08-06 2003-09-02 Lightcross, Inc. Optical component having a flat top output
US20060050747A1 (en) * 2004-09-08 2006-03-09 Trutna William R Jr Frequency-tunable light sources and methods of generating frequency-tunable light
US9318868B2 (en) * 2011-09-07 2016-04-19 Skorpios Technologies, Inc. Tunable hybrid laser with carrier-induced phase control
JP2011204895A (ja) * 2010-03-25 2011-10-13 Sumitomo Electric Ind Ltd 半導体レーザ装置
CN102646926B (zh) * 2012-04-11 2013-09-25 四川马尔斯科技有限责任公司 基于复合mzi及反射光栅的波长可调谐激光器

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102282458A (zh) * 2009-03-12 2011-12-14 特拉维夫大学未来技术发展有限合伙公司 发光腔内干涉传感器
US20120057079A1 (en) * 2009-10-13 2012-03-08 Skorpios Technolgies, Inc. Method and system for hybrid integration of a tunable laser for a cable tv transmitter
CN102646927A (zh) * 2012-04-11 2012-08-22 四川马尔斯科技有限责任公司 基于波导反射光栅阵列的波长可调谐外腔激光器
CN103457155A (zh) * 2013-07-26 2013-12-18 李若林 混合集成复合腔波长可调谐激光发射器
CN104393484A (zh) * 2014-11-27 2015-03-04 华中科技大学 一种大范围调谐激光器及其调谐方法

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