
- Photonics Research
- Vol. 10, Issue 5, 1271 (2022)
Abstract
1. INTRODUCTION
Embedding semiconductor lasers with Bragg gratings as wavelength-selective feedback mechanisms is a well-established approach to achieving high-quality single-frequency lasing. In conjunction with the distinctive properties of various compound semiconductor gain materials, distributed feedback (DFB) and distributed Bragg reflector (DBR) lasers are finding a wide range of applications in both classical and quantum domains, such as with InGaAs emitting in the near infrared for optical communication [1], with GaAs or GaAsP in the red spectral range [2] for atomic clocks [3], atom interferometry [4], and efficient optical pumping [5], with GaSb or InAs/AlSb in the middle to far infrared [6] for trace-gas sensing [7], and with nitride semiconductors in the green to ultraviolet for absorption spectroscopy [8] and high-density data storage [9].
For optical data interconnect applications, the 1310 nm band is of particular interest for low-cost wavelength division multiplexing (WDM) systems [10], 5G and 6G optical networks [11], as well as for LiDAR [12,13] and sensing [14,15]. Compared with conventional InGaAs/InGaAlAs quantum well (QW) materials emitting in the same wavelength range, self-assembled InAs/GaAs quantum dots (QDs) have achieved superior performance, including lower threshold currents [16] and higher-temperature stability [17] due to the zero-dimensional (0D) carrier confinement in QDs. A highly desirable feature of QD lasers is their ultralow relative intensity noise (RIN) [18–20] originating from their very low linewidth enhancement factor
For DFB lasers, the buried Bragg gratings, as first realized in InP-based 1550 nm lasers, are conventionally placed on top of the active layer and fabricated through a regrowth process after grating definition and etching. The proximity to the waveguide allows the grating to intercept the optical field with a high coupling coefficient
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However, the regrowth process represents poor productivity for many material systems. For GaAs-based laser devices, an InGaP upper cladding layer requires wafer transfer from MBE to MOCVD systems, while an AlGaAs upper cladding layer requires rigorous pretreatment before regrowth via an ultrahigh-vacuum MBE chamber. Harder still, the regrowth process for GaN(Sb)-based lasers suffers from lack of a contamination-free AlGaN(Sb) regrowth process or other latticed-matched cladding materials with sufficient bandgap and refractive index contrasts.
An alternative, regrowth-free approach uses Bragg gratings etched alongside a ridge waveguide to form a laterally coupled DFB (LC-DFB) laser. For InP-based laser structures, the gratings can be fabricated simultaneously during the waveguide etching process. Using an aluminum-containing stop-etch layer and a chemically selective recipe [35,36], the grating penetration depth can be precisely delimited to just above the active layer to achieve a precise
To circumvent this problem, in a previous work, the authors chose to etch the lateral grating deeply through the active region so that the grating etch depth no longer affects
In this paper, we demonstrate a novel dielectric grating structure placed alongside single transverse mode ridge waveguides that have a precisely controlled trapezoid cross-sectional profile etched to a depth just above the active layer. Fabricated in an amorphous silicon (
We implemented the novel structure on an InAs/GaAs QD gain material, producing LC-DFB laser arrays emitting across the 1300 nm band on a 0.8 THz local area network wavelength division multiplexing (LWDM) grid. The devices emit more than 26.6 mW of single-mode output power at room temperature and a typical SMSR greater than 52.7 dB. They also demonstrate ultralow RIN of
2. DESIGN AND FABRICATION OF THE LC-DFB QD LASER
The InAs/GaAs QD laser structure, in a typical p-i-n configuration [Fig. 1(a)], was grown on 3-inch (1 inch = 2.54 cm) semi-insulating GaAs (001) substrates in a solid-source MBE chamber. First, a 500 nm Si-doped GaAs buffer layer and a 1.8 μm
Figure 1.Material properties of InAs/GaAs QD lasers. (a) Cross-sectional scanning electron microscope (SEM) image of layer stack of the epi-wafer. The inset is the transmission electron microscope (TEM) image of the five QD layers. (b) Photoluminescence spectrum of the QD active layers on GaAs. The inset shows the atomic force microscope (AFM) image of an uncapped QD layer. (c) Light–current–voltage (
The as-grown wafers were then processed into LC-DFB laser arrays. As shown in Fig. 2(a), a waveguide width of 2.1 μm and a depth of 1.7 μm are used to support only the lowest-order transverse mode (TE00). The ridge waveguides were patterned using electron beam lithography (EBL) and etched using an optimized chlorine-based GaAs inductively coupled plasma reactive-ion etching (ICP-RIE) process, with a trapezoid cross section, sidewall slope of
Figure 2.(a) Schematic of the DFB laser structure, including the near-zero “footing” trapezoid waveguide and the
A 10 nm
The corrugations were subsequently covered with a 200 nm layer of
3. LASING CHARACTERISTICS OF THE FABRICATED LC-DFB QD LASER
At room temperature (25°C), a typical
Figure 3.(a) Typical
The experimental value of
Stable single-mode operation was observed at CW currents up to 150 mA in the temperature range of 20°C–50°C, with a linear wavelength–temperature tuning rate of 0.12 nm/°C and a quadratic wavelength–current tuning curve [Figs. 4(a) and 4(b)]. It is noteworthy that the laser maintains single-mode operation across the entire current range. This high single-mode quality is credited to the novel
Figure 4.(a) Wavelength shift with injection currents; (b) wavelength shift with heat-sink temperature; (c), (d) optical spectra and lasing frequencies of an LWDM DFB laser array measured at 100 mA.
Across each eight-device bar, channel spacing of
4. RELATIVE INTENSITY NOISE AND EXTERNAL FEEDBACK SENSITIVITY
The RIN across the frequency range of 2.5–20 GHz is assessed using a commercial system (SYCATUS A0010A), measuring
Figure 5.Measured RIN spectra at several bias currents at 25°C.
Finally, the performance of the QD LC-DFB lasers under coherent optical feedback was assessed using the optical measurement setups shown schematically in Fig. 6(a). The emission from the QD laser AR facet is coupled into the feedback test system by a lensed fiber with coupling efficiency of 20%–30%, and divided into feedback and detection paths by a 90/10 fiber coupler. On the feedback path (10% of the coupled power), a fibered optical circulator is used to feed the light back to the laser cavity. Since the external cavity resonance frequency (17.25 MHz in this stage) is much less than the laser RO frequency, the impact of the feedback phase is negligible. The feedback strength
Figure 6.(a) Experimental setup used for the long-delay feedback measurements. LF, lens fiber; PM, power meter; BOA, boost optical amplifier; OSA, optical spectrum analyzer; RIN, relative intensity noise; PC, polarization controller; ISO, optical isolator; BPF, bandpass filter. (b) Evolution of the SMSR with increasing feedback strength; the inset is the optical spectrum of the DFB laser as the feedback strength increases. (c) Change of RIN in the same DFB laser under
Figures 6(b) and 6(c) present the evolution of SMSR and RIN with the laser operating at
5. DISCUSSION
Given the rapid development of QD-DFB lasers at 1310 nm on both GaAs and silicon substrates, it is useful to compare the performance of our device with those reported in the literature. Table 1 lists the threshold current (current density), power, highest work temperature, SMSR, RIN, and optical feedback tolerance of reported DFB lasers together with our device. In general, compared with commercial QW lasers, QD lasers exhibit excellent performance in terms of high operating temperature, low RIN, and high optical feedback tolerance owing to their stronger carrier confinement, larger damping factor, and smaller
Comparison of the Performance of Our Device with Reference QD DFB Laser at 1310 nm
Year | Substrate | Grating | Threshold Current | Threshold | Power (mW) | SMSR (dB) | RIN | Anti- | Ref. | ||
2003 | GaAs | GaAs sidewall | – | 3 | – | 9.3 | 50 | – | – | –14 | [ |
2005 | GaAs | Metal sidawall | – | 5 | – | 12 | – | – | – | [ | |
2011 | GaAs | InGa/GaAs buried | 4 | 6.8 | – | 10 | 45 | 80 | – | – | [ |
2011 | GaAs | Cr sidewall | – | 18 | 1500 | 53 | 85 | – | –12 | [ | |
2014 | GaAs | InGa/GaAs buried | 2.5 | 43.8 | 1830 | 34 | 58 | 60 | – | – | [ |
2018 | GaAs | GaAs sidewall | – | 30 | 1710 | 23 | 51 | – | – | – | [ |
2018 | GaAs | InGa/GaAs buried | 4 | 6.2 | 1107 | 20 | 70 | –150 | –8 | [ | |
2018 | Heterogenous integrated GaAs/Si | Si | 7.7 | 9.5 | 205 | 2.5 | 47 | 100 | – | – | [ |
2018 | Monolithic integrated GaAS/Si | GaAs sidewall | 4.2 | 12 | 550 | 1.5 | 50 | – | – | – | [ |
2020 | Monolithic integrated GaAs/Si | AIGaAs/GaAs buried | 4.5 | 20 | 440 | 4.4 | 50 | 70 | – | – | [ |
2021 | Monolithic integrated GaAs/Si | Si | 5 | 4 | 250 | 2.8 | 60 | 75 | – | – | [ |
2021 | Heterogeneous GaAs/oxide/Si | Si | 15 | 6.7 | 134 | 7 | 61 | 70 | –125 | – | [ |
2021 | GaAs | InGaP/GaAs buried | 1.6 | 9.3 | – | 15 | 50 | 55 | –150 | –6 | [ |
2021 | GaAs | Amorphous Si sidewall | 2.0 | 18 | 571 | 26.6 | 52.7 | 55 | –165 | –12.3 | This work |
To conclude, by implementing a novel first-order
The novel grating structure affords accurate and deterministic grating coupling coefficient
APPENDIX A: CALCULATED AND EXPERIMENTAL VALUE OF κ
According to coupled mode theory, coupling coefficient
The
Material Refractive Index Used in the Simulation at Wavelength of 1310 nm
Material | Refractive Index |
---|---|
GaAs | 3.41 |
3.25 | |
1.75 | |
Si | 3.49 |
1.45 | |
BCB | 1.56 |
The material B-staged bisbenzocyclobutene (BCB, type: CYCLOTENE 4022-35) is used to planarize the laser ridge waveguide. Therefore, in our simulation, the background refractive index is set as 1.56.
Figure 7.Coupling coefficient
Experimental grating coupling coefficient
References
[1] D. Botez, G. J. Herskowitz. Components for optical communications systems: a review. Proc. IEEE, 68, 689-731(1980).
[2] O. Brox, F. Bugge, A. Mogilatenko, E. Luvsandamdin, A. Wicht, H. Wenzel, G. Erbert. Distributed feedback lasers in the 760 to 810 nm range and epitaxial grating design. Semicond. Sci. Technol., 29, 095018(2014).
[3] E. Di Gaetano, S. Watson, E. McBrearty, M. Sorel, D. J. Paul. Sub-megahertz linewidth 780.24 nm distributed feedback laser for 87Rb applications. Opt. Lett., 45, 3529-3532(2020).
[4] V. Schkolnik, O. Hellmig, A. Wenzlawski, J. Grosse, A. Kohfeldt, K. Döringshoff, A. Wicht, P. Windpassinger, K. Sengstock, C. Braxmaier, M. Krutzik, A. Peters. A compact and robust diode laser system for atom interferometry on a sounding rocket. Appl. Phys. B, 122, 217(2016).
[5] Y. He, H. An, J. Cai, C. Galstad, S. Macomber, M. Kanskar. 808 nm broad area DFB laser for solid-state laser pumping application. Electron. Lett., 45, 163-164(2009).
[6] S. Stephan, D. Frederic, A. Markus-Christian. Novel InP- and GaSb-based light sources for the near to far infrared. Semicond. Sci. Technol., 31, 113005(2016).
[7] M. Hoppe, C. Aßmann, S. Schmidtmann, T. Milde, M. Honsberg, T. Schanze, J. Sacher. GaSb-based digital distributed feedback filter laser diodes for gas sensing applications in the mid-infrared region. J. Opt. Soc. Am. B, 38, B1-B8(2021).
[8] S. Najda, P. Perlin, M. Leszczyński, T. Slight, W. Meredith, M. Schemmann, H. Moseley, J. Woods, R. Valentine, S. Kalra, P. Mossey, E. Theaker, M. Macluskey, G. Mimnagh, W. Mimnagh. A multi-wavelength (u.v. to visible) laser system for early detection of oral cancer. Proc. SPIE, 9328, 932809(2015).
[9] T. Miyajima, T. Tojyo, T. Asano, K. Yanashima, S. Kijima, T. Hino, M. Takeya, S. Uchida, S. Tomiya, K. Funato, T. Asatsuma, T. Kobayashi, M. Ikeda. GaN-based blue laser diodes. J. Phys.: Condens. Matter, 13, 7099(2001).
[10] J. C. Palais. Fiber Optic Communications(1988).
[11] T. Sudo, Y. Matsui, G. Carey, A. Verma, D. Wang, V. Lowalekar, M. Kwakernaak, F. Khan, N. Dalida, R. Patel, A. Nickel, B. Young, J. Zeng, Y. L. Ha, C. Roxlo. Challenges and opportunities of directly modulated lasers in future data center and 5G networks. Optical Fiber Communications Conference and Exhibition (OFC), 1-3(2021).
[12] C. P. Hsu, B. Li, B. Solano-Rivas, A. R. Gohil, P. H. Chan, A. D. Moore, V. Donzella. A review and perspective on optical phased array for automotive LiDAR. IEEE J. Sel. Top. Quantum Electron., 27, 8300416(2021).
[13] D. N. Hutchison, J. Sun, J. K. Doylend, R. Kumar, J. Heck, W. Kim, C. T. Phare, A. Feshali, H. Rong. High-resolution aliasing-free optical beam steering. Optica, 3, 887-890(2016).
[14] M.-C. Amann, M. Ortsiefer. Long-wavelength (
[15] A. Liu, P. Wolf, J. A. Lott, D. Bimberg. Vertical-cavity surface-emitting lasers for data communication and sensing. Photon. Res., 7, 121-136(2019).
[16] H. Y. Liu, S. L. Liew, T. Badcock, D. J. Mowbray, M. S. Skolnick, S. K. Ray, T. L. Choi, K. M. Groom, B. Stevens, F. Hasbullah, C. Y. Jin, M. Hopkinson, R. A. Hogg. p-doped 1.3 μm InAs/GaAs quantum-dot laser with a low threshold current density and high differential efficiency. Appl. Phys. Lett., 89, 073113(2006).
[17] T. Kageyama, K. Nishi, M. Yamaguchi, R. Mochida, Y. Maeda, K. Takemasa, Y. Tanaka, T. Yamamoto, M. Sugawara, Y. Arakawa. Extremely high temperature (220°C) continuous-wave operation of 1300-nm-range quantum-dot lasers. The European Conference on Lasers and Electro-Optics, PDA_1(2011).
[18] Y.-G. Zhou, C. Zhou, C.-F. Cao, J.-B. Du, Q. Gong, C. Wang. Relative intensity noise of InAs quantum dot lasers epitaxially grown on Ge. Opt. Express, 25, 28817-28824(2017).
[19] M. Liao, S. Chen, Z. Liu, Y. Wang, L. Ponnampalam, Z. Zhou, J. Wu, M. Tang, S. Shutts, Z. Liu, P. M. Smowton, S. Yu, A. Seeds, H. Liu. Low-noise 1.3 μm InAs/GaAs quantum dot laser monolithically grown on silicon. Photon. Res., 6, 1062-1066(2018).
[20] A. Capua, L. Rozenfeld, V. Mikhelashvili, G. Eisenstein, M. Kuntz, M. Laemmlin, D. Bimberg. Direct correlation between a highly damped modulation response and ultra low relative intensity noise in an InAs/GaAs quantum dot laser. Opt. Express, 15, 5388-5393(2007).
[21] D. A. I. Marpaung. High dynamic range analog photonic links(2009).
[22] B. Dong, J.-D. Chen, F.-Y. Lin, J. C. Norman, J. E. Bowers, F. Grillot. Dynamic and nonlinear properties of epitaxial quantum-dot lasers on silicon operating under long- and short-cavity feedback conditions for photonic integrated circuits. Phys. Rev. A, 103, 033509(2021).
[23] H. Huang, J. Duan, B. Dong, J. Norman, D. Jung, J. E. Bowers, F. Grillot. Epitaxial quantum dot lasers on silicon with high thermal stability and strong resistance to optical feedback. APL Photon., 5, 016103(2020).
[24] B. Dong, J. Duan, H. Huang, J. C. Norman, K. Nishi, K. Takemasa, M. Sugawara, J. E. Bowers, F. Grillot. Dynamic performance and reflection sensitivity of quantum dot distributed feedback lasers with large optical mismatch. Photon. Res., 9, 1550-1558(2021).
[25] J. C. Norman, D. Jung, Y. Wan, J. E. Bowers. Perspective: the future of quantum dot photonic integrated circuits. APL Photon., 3, 030901(2018).
[26] C. Hantschmann, Z. Liu, M. Tang, S. Chen, A. J. Seeds, H. Liu, I. H. White, R. V. Penty. Theoretical study on the effects of dislocations in monolithic III-V lasers on silicon. J. Lightwave Technol., 38, 4801-4807(2020).
[27] J. C. Norman, D. Jung, Z. Zhang, Y. Wan, S. Liu, C. Shang, R. W. Herrick, W. W. Chow, A. C. Gossard, J. E. Bowers. A review of high-performance quantum dot lasers on silicon. IEEE J. Quantum Electron., 55, 2000511(2019).
[28] S. Chen, W. Li, J. Wu, Q. Jiang, M. Tang, S. Shutts, S. N. Elliott, A. Sobiesierski, A. J. Seeds, I. Ross, P. M. Smowton, H. Liu. Electrically pumped continuous-wave III–V quantum dot lasers on silicon. Nat. Photonics, 10, 307-311(2016).
[29] J. C. Norman, R. P. Mirin, J. E. Bowers. Quantum dot lasers—history and future prospects. J. Vac. Sci. Technol. A, 39, 020802(2021).
[30] D. Jung, R. Herrick, J. Norman, K. Turnlund, C. Jan, K. Feng, A. C. Gossard, J. E. Bowers. Impact of threading dislocation density on the lifetime of InAs quantum dot lasers on Si. Appl. Phys. Lett., 112, 153507(2018).
[31] T. Septon, A. Becker, S. Gosh, G. Shtendel, V. Sichkovskyi, F. Schnabel, A. Sengül, M. Bjelica, B. Witzigmann, J. P. Reithmaier, G. Eisenstein. Large linewidth reduction in semiconductor lasers based on atom-like gain material. Optica, 6, 1071-1077(2019).
[32] Z. Lu, K. Zeb, J. Liu, E. Liu, L. Mao, P. Poole, M. Rahim, G. Pakulski, P. Barrios, W. Jiang, D. Poitras. Quantum dot semiconductor lasers for 5G and beyond wireless networks. Proc. SPIE, 11690, 116900N(2021).
[33] K. Takada, Y. Tanaka, T. Matsumoto, M. Ekawa, H. Z. Song, Y. Nakata, M. Yamaguchi, K. Nishi, T. Yamamoto, M. Sugawara, Y. Arakawa. Wide-temperature-range 10.3 Gbit/s operations of 1.3 μm high-density quantum-dot DFB lasers. Electron. Lett., 47, 206-208(2011).
[34] Y. Wan, J. C. Norman, Y. Tong, M. J. Kennedy, W. He, J. Selvidge, C. Shang, M. Dumont, A. Malik, H. K. Tsang, A. C. Gossard, J. E. Bowers. 1.3 μm quantum dot-distributed feedback lasers directly grown on (001) Si. Laser Photon. Rev., 14, 2000037(2020).
[35] C. B. Cooper, S. Salimian, H. F. Macmillan. Reactive ion etch characteristics of thin InGaAs and AlGaAs stop-etch layers. J. Electron. Mater., 18, 619-622(1989).
[36] G. C. Desalvo, W. F. Tseng, J. Comas. ChemInform abstract: etch rates and selectivities of citric acid/hydrogen peroxide on GaAs, Al0.3Ga0.7As, In0.2Ga0.8As, In0.53Ga0.47As, In0.52Al0.48As, and InP. ChemInform, 23, 309(1992).
[37] Q. Li, X. Wang, Z. Zhang, H. Chen, Y. Huang, C. Hou, J. Wang, R. Zhang, J. Ning, J. Min, C. Zheng. Development of modulation p-doped 1310 nm InAs/GaAs quantum dot laser materials and ultrashort cavity Fabry–Perot and distributed-feedback laser diodes. ACS Photon., 5, 1084-1093(2018).
[38] S. Forouhar, R. M. Briggs, C. Frez, K. J. Franz, A. Ksendzov. High-power laterally coupled distributed-feedback GaSb-based diode lasers at 2 μm wavelength. Appl. Phys. Lett., 100, 031107(2012).
[39] S. Masui, K. Tsukayama, T. Yanamoto, T. Kozaki, S.-I. Nagahama, T. Mukai. CW operation of the first-order AlInGaN 405 nm distributed feedback laser diodes. Jpn. J. Appl. Phys., 45, L1223-L1225(2006).
[40] Y. Wang, S. Chen, Y. Yu, L. Zhou, L. Liu, C. Yang, M. Liao, M. Tang, Z. Liu, J. Wu, W. Li, I. Ross, A. J. Seeds, H. Liu, S. Yu. Monolithic quantum-dot distributed feedback laser array on silicon. Optica, 5, 528-533(2018).
[41] C. A. Yang, S. W. Xie, Y. Zhang, J. M. Shang, S. S. Huang, Y. Yuan, F. H. Shao, Y. Zhang, Y. Q. Xu, Z. C. Niu. High-power, high-spectral-purity GaSb-based laterally coupled distributed feedback lasers with metal gratings emitting at 2 μm. Appl. Phys. Lett., 114, 021102(2019).
[42] A. Laakso, J. Karinen, M. Dumitrescu. Modeling and design particularities for distributed feedback lasers with laterally-coupled ridge-waveguide surface gratings. Proc. SPIE, 7933, 79332K(2011).
[43] W. Streifer, D. Scifres, R. Burnham. Coupling coefficients for distributed feedback single- and double-heterostructure diode lasers. IEEE J. Quantum Electron., 11, 867-873(1975).
[44] W.-Y. Choi, J. C. Chen, C. G. Fonstad. Evaluation of coupling coefficients for laterally-coupled distributed feedback lasers. Jpn. J. Appl. Phys., 35, 4654-4659(1996).
[45] J. Duan, H. Huang, B. Dong, J. C. Norman, Z. Zhang, J. E. Bowers, F. Grillot. Dynamic and nonlinear properties of epitaxial quantum dot lasers on silicon for isolator-free integration. Photon. Res., 7, 1222-1228(2019).
[46] F. Grillot, B. Thedrez, D. Guang-Hua. Feedback sensitivity and coherence collapse threshold of semiconductor DFB lasers with complex structures. IEEE J. Quantum Electron., 40, 231-240(2004).
[47] Q. Zou, K. Merghem, S. Azouigui, A. Martinez, A. Accard, N. Chimot, F. Lelarge, A. Ramdane. Feedback-resistant p-type doped InAs/InP quantum-dash distributed feedback lasers for isolator-free 10 Gb/s transmission at 1.55 μm. Appl. Phys. Lett., 97, 231115(2010).
[48] H. Su, L. Zhang, A. L. Gray, R. Wang, T. C. Newell, K. J. Malloy, L. F. Lester. High external feedback resistance of laterally loss-coupled distributed feedback quantum dot semiconductor lasers. IEEE Photon. Technol. Lett., 15, 1504-1506(2003).
[49] H. Su, L. F. Lester. Dynamic properties of quantum dot distributed feedback lasers: high speed, linewidth and chirp. J. Phys. D, 38, 2112-2118(2005).
[50] S. Azouigui, D.-Y. Cong, A. Martinez, K. Merghem, Q. Zou, J.-G. Provost, B. Dagens, M. Fischer, F. Gerschütz, J. Koeth, I. Krestnikov, A. Kovsh, A. Ramdane. Temperature dependence of dynamic properties and tolerance to optical feedback of high-speed 1.3 μm DFB quantum-dot lasers. IEEE Photon. Technol. Lett., 23, 582-584(2011).
[51] M. Stubenrauch, G. Stracke, D. Arsenijević, A. Strittmatter, D. Bimberg. 15 Gb/s index-coupled distributed-feedback lasers based on 1.3 μm InGaAs quantum dots. Appl. Phys. Lett., 105, 011103(2014).
[52] M. Matsuda, N. Yasuoka, K. Nishi, K. Takemasa, T. Yamamoto, M. Sugawara, Y. Arakawa. Low-noise characteristics on 1.3-μm-wavelength quantum-dot DFB lasers under external optical feedback. IEEE International Semiconductor Laser Conference (ISLC), 1-2(2018).
[53] S. Uvin, S. Kumari, A. De Groote, S. Verstuyft, G. Lepage, P. Verheyen, J. Van Campenhout, G. Morthier, D. Van Thourhout, G. Roelkens. 1.3 μm InAs/GaAs quantum dot DFB laser integrated on a Si waveguide circuit by means of adhesive die-to-wafer bonding. Opt. Express, 26, 18302-18309(2018).
[54] Y. Wan, C. Xiang, J. Guo, R. Koscica, M. J. Kennedy, J. Selvidge, Z. Zhang, L. Chang, W. Xie, D. Huang, A. C. Gossard, J. E. Bowers. High speed evanescent quantum-dot lasers on Si. Laser Photon. Rev., 15, 210057(2021).
[55] D. Liang, S. Srinivasan, A. Descos, C. Zhang, G. Kurczveil, Z. Huang, R. Beausoleil. High-performance quantum-dot distributed feedback laser on silicon for high-speed modulations. Optica, 8, 591-593(2021).
[56] G. Liu, G. Zhao, J. Sun, D. Gao, Q. Lu, W. Guo. Experimental demonstration of DFB lasers with active distributed reflector. Opt. Express, 26, 29784-29795(2018).

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