楊四剛 副研究員

中國北京市海淀區(qū)清華大學(xué)電子工程系 100084

電話： 86-10-62784784

辦公室位置：羅姆樓3-101

電子郵箱：ysg@tsinghua.edu.cn

個人簡介: 楊四剛，湖北仙桃人。2008年于清華大學(xué)電子工程系畢業(yè)獲工學(xué)博士學(xué)位。其間研究工作兩次被光電子領(lǐng)域介紹研究進(jìn)展的雜志Photonics Spectra予以專題報道。2008年8月至2010年7月在香港大學(xué)電機電子工程系從事博士后研究，從事光纖參量放大以及光纖參量振蕩器的研究�，F(xiàn)在清華大學(xué)電子工程系工作，任副研究員。過去及現(xiàn)在的主要研究方向有：光纖方向計算電磁學(xué)，光子晶體光纖，光纖非線性，光纖參量放大、參量振蕩，硅基頻率梳以及太赫茲波等。曾獲2004年亞太光通信會議“ Best Student Paper Award”；清華大學(xué)2008年“優(yōu)秀博士學(xué)位論文二等獎”等獎項。他是美國光學(xué)學(xué)會（OSA）的刊物Optics Letters, Optics Express, Journal of the Optical Society of America B, Applied Optics以及IEEE相關(guān)刊物的審稿人。

教育背景1996.9～2000.7    東北大學(xué)                     學(xué)士
2000.9～2003.7    華中科技大學(xué)              碩士
2003.9～2008.2    清華大學(xué)                     博士

工作履歷2008.8～2010.7     香港大學(xué)電機與電子工程學(xué)系   博士后
2010.8至今            清華大學(xué)電子工程系                  助理研究員、副研究員

學(xué)術(shù)兼職國際電子電氣工程師協(xié)會（IEEE）會員
美國光學(xué)學(xué)會（OSA）會員
知名期刊審稿人：OSA OL/OE/JOSAB/AO/COL ；IEEE PTL/JLT

研究領(lǐng)域光子晶體光纖：是繼基于傳統(tǒng)摻雜工藝的單模光纖和高非線性光纖之后出現(xiàn)的一種新型光纖。其包層由折射率周期性分布的透光材料形成，纖芯由周期性被破壞的缺陷形成。按導(dǎo)光機理的不同，主要分為折射率引導(dǎo)型光子晶體光纖和光子帶隙型光子晶體光纖。由于其獨特的結(jié)構(gòu)，其雙折射、有效模式面積、色散、非線性等參數(shù)具有高度可調(diào)節(jié)性。使之在光譜學(xué)、生物醫(yī)學(xué)、光纖傳感、光纖激光器、非線性光學(xué)、光通信等領(lǐng)域具有廣泛的應(yīng)用前景。

光纖參量放大器和光纖參量振蕩器：激光的出現(xiàn)，對人類的生活產(chǎn)生了革命性的影響。在一些新的應(yīng)用領(lǐng)域，如生物、醫(yī)療、海洋開發(fā)以及大氣探測等領(lǐng)域，需要在傳統(tǒng)激光器不能覆蓋的新波段工作的光源。光纖參量放大器具有帶寬大、增益高、噪聲低等特點。其突出的一個優(yōu)點是其增益帶寬由泵浦波長和增益介質(zhì)共同決定。通過選擇合適的泵浦波長和增益介質(zhì)，幾乎在可任意波段輻射。光子晶體光纖具有非常靈活的色散特性�；�于光子晶體光纖的參量振蕩器，可在傳統(tǒng)激光器不能工作的波段提供可調(diào)諧的光輻射，是一種非常具有應(yīng)用前景的新波長光源。

波長變換：全光波長變換，是通過非線性媒質(zhì)，將已有波長變換到新的波長。 變換后的波長可以覆蓋從紫外到中紅外的大跨度波段。因此波長變換提供了一種產(chǎn)生特殊波長輻射的有效手段。光子晶體光纖由于其折射率調(diào)制大，具有高非線性，色散特性非常靈活，是進(jìn)行波長變換的理想介質(zhì)。因此，基于光子晶體光纖的波長變換，是目前研究的熱點問題。

太赫茲波：太赫茲波是頻率介于微波和紅外之間的一種電磁輻射。作為連接傳統(tǒng)電磁波和光波的橋梁, 太赫茲波兼具光波和微波的優(yōu)點，被看作是電磁頻譜研究中最后一個前沿領(lǐng)域。太赫茲波因在諸多領(lǐng)域具有重要的應(yīng)用前景日益受到學(xué)術(shù)界和工業(yè)界的重視，是當(dāng)前研究的難點和熱點課題。主要研究太赫茲波的產(chǎn)生、傳播以及應(yīng)用等。

研究概況主要從事光纖及波導(dǎo)非線性研究。過去及現(xiàn)在的主要研究工作包括光纖方向計算電磁學(xué)、光子晶體光纖理論仿真、光纖非線性、光纖參量放大和參量振蕩、太赫茲波、硅基頻率梳等。實際指導(dǎo)的博士生2014年入選第19屆清華大學(xué)“學(xué)術(shù)新秀”，并被評為2014年清華大學(xué)優(yōu)秀博士畢業(yè)生。實際指導(dǎo)的博士論文“基于光子晶體光纖非線性效應(yīng)的超寬帶可調(diào)諧光源”入選”Springer Theses” (the best of best)以英文版出版。負(fù)責(zé)指導(dǎo)的碩士生一人被評為2014年北京市優(yōu)秀畢業(yè)生。所發(fā)表論文中一篇被期刊Journal of Optics評為”Highlights of 2014”；一篇被期刊Electronics Letters予以專題報道；先后兩次被Photonics Spectra予以專題報道。

學(xué)術(shù)成果Journal Papers

[1] Sigang Yang, Xiaojian Wang, Zhaohui Wu, Chen Jin, Minghua Chen, Shizhong Xie, Narrow linewidth terahertz generation engined by all-fiber parametric optical source, IEEE Photonics Journal, 7(6), 1300407, 2015.
[2] Lei Zhang&, Sigang Yang*,Xiaojian Wang, Doudou Gou, Hongwei Chen, Minghua Chen, and Shizhong Xie, Demonstration of optical parametric gain generation at 1 μm regime based on a photonic crystal fiber pumped by picosecond mode-locked ytterbium- doped fiber laser, Journal of Optics, 16(1), 015202, 2014.
[3] Lei Zhang&, Sigang Yang*, Xiaojian Wang, Doudou Gou,Wei Chen, Wenyong Luo, Hongwei Chen, Minghua Chen, and Shizhong Xie, Photonic Crystal Fiber Based Wavelength- Tunable Optical Parametric Amplifier and Picosecond Pulse Generation，IEEE Photonics Journal, 6(5),1501908, 2014.
[4] Lei Zhang&, Sigang Yang*, Xiaojian Wang, Doudou Gou, Hongwei Chen, Minghua Chen, and Shizhong Xie, High-efficiency all-fiber optical parametric oscillator based on photonic crystal fibers pumped by ytterbium-doped fiber laser, Electronics Letters, 50(8), 624-626,2014.
[5] Lei Zhang&, Sigang Yang*, Xiaojian Wang, Doudou Gou, Hongwei Chen, Minghua Chen, and Shizhong Xie, Picosecond photonic crystal fiber-based doubly resonant optical parametric oscillator, IEEE Photonics Technology Letters, 26(7), 682-685, 2014.
[6] Gou Dou-Dou&, Yang Si-Gang*, Zhang Lei,Wang Xiao-Jian, Chen Hong-Wei, Chen Ming-Hua,Xie Shi-Zhong, Chen Wei, and Luo Wen-Yong, Fiber optical parametric oscillator based on photonic crystal fiber pumped with all-normal-dispersion mode-locked Yb:fiber laser, Chinese Physics B, 23(11), 114204,2014.
[7] Lei Zhang, Sigang Yang, Ying Han, Hongwei Chen, Minghua Chen, and Shizhong Xie, Optical parametric generation with two pairs of gain bands based on a photonic crystal fiber, Optics Communications, 300, 22-26, 2013.
[8] Lei Zhang&, Sigang Yang*, Xiaojian Wang, Doudou Gou, Xiangliang Li, Hongwei Chen, Minghua Chen, and Shizhong Xie, Widely tunable all-fiber optical parametric oscillator based on a photonic crystal fiber pumped by a picosecond ytterbium-doped fiber laser, Optics Letters, 38(22), 4534-4537, 2013.
[9] Lei Zhang&, Sigang Yang*, Pengxiao Li, Xiaojian Wang, Doudou Gou, Wei Chen, Wenyong Luo, Hongwei Chen, Minghua Chen, and Shizhong Xie, An all-fiber continuously time-dispersion- tuned picosecond optical parametric oscillator at 1 μm region, Optics Express, 21(21), 25167-25173,2013.
[10] Lei Zhang&, Sigang Yang*, Ying Han, Hongwei Chen, Minghua Chen, and Shizhong Xie, Simultaneous generation of tunable giant dispersive waves in the visible and mid-infrared regions based on photonic crystal fibers, Journal of Optics, 15(7), 075201,2013.
[11] Sigang Yang, Kenneth K. Y. Wong, Minghua Chen, Shizhong Xie，F(xiàn)iber Optical Parametric Oscillator Based on Highly Nonlinear Dispersion-Shifted Fiber，F(xiàn)rontiers of Optoelectronics，6(1):25-29, 2013. Invited.
[12] Feifei Yin, Sigang Yang, Hongwei Chen, Minghua Chen, and Shizhong Xie, Tunable single-longitudinal-mode Ytterbium all fiber laser with saturable-absorber-based auto-tracking filter. Optics Communications. 285:2702-2706, 2012.
[13] Feifei Yin, Sigang Yang, Hongwei Chen, Minghua Chen, and Shizhong Xie, 60-nm-wide Tunable Single-longitudinal-mode Ytterbium Fiber Laser with Passive Multiple Ring Cavity, IEEE Photonics Technology Letters. 23(22):1658-1660, 2011.
[14] Sigang Yang, Chi Zhang, Yue Zhou, and Kenneth Kin-Yip Wong, “Two-Wavelength Square-Waveform Generation Based on Fiber Optical Parametric Oscillator,” IEEE Transactions on Microwave Theory and Techniques, 58(11): 3381-3386,2010.
[15] Sigang Yang, Kim K. Y. Cheung, Yue Zhou, and Kenneth K. Y. Wong, “Tunable Single-Longitudinal-Mode Fiber Optical Parametric Oscillator,” Optics Letters, 35(4):481-483, 2010.
[16] Sigang Yang, Kim K. Y. Cheung, Yue Zhou, and Kenneth K. Y. Wong, “Dispersion-Tuned Harmonically Mode-Locked Fiber-Optical Parametric Oscillator,” IEEE  Photonics Technology Letters,22(8):580-582,2010.
[17] Sigang Yang, Yue Zhou, Jia Li, and Kenneth K.-Y. Wong, “Actively Mode-Locked Fiber Optical Parametric Oscillator,” IEEE Journal of Selected Topics in Quantum Electronics, 15(2):393-398, 2009.
[18] Sigang Yang, Xing Xu, Yue Zhou, Kim K. Y. Cheung, and Kenneth K. Y. Wong, “Continuous-Wave Single-Longitudinal-Mode Fiber Optical Parametric Oscillator with Reduced Pump Threshold,” IEEE Photonics Technology Letters,21(24):1870-1872, 2009.
[19]Sigang Yang, Hongwei Chen, Ciyuan Qiu,Ming Chen,Minghua Chen,Shizhong Xie,Jinyan Li and Wei Chen. “Slow-light delay enhancement in small-core pure silica photonic crystal fiber based on Brillouin scattering,” Optics Letters, 33(2),95-97,2008.
[20]  Sigang Yang, Yejin Zhang, Jinyan Li, Wei Chen, Lina He, and Shizhong Xie. “Experimental Study of Mode Field Evolution of Dual-Core Photonic Crystal Fiber,” IEEE Photonics Technology Letters, 19(19):1523- 1525,2007.
[21] Sigang Yang, Yejin Zhang, Lina He, and Shizhong Xie. “Broadband dispersion-compensating photonic crystal fiber,” Optics Letters, 31(19):2830-2832,2006.
[22] Sigang Yang, Yejin Zhang, Xiaozhou Peng, Yang Lu, Shizhong Xie. “Theoretical study and experimental fabrication of high negative dispersion photonic crystal fiber with large area mode field,” Optics Express, 14(7):3015-3023, 2006.

Conference Papers

[1] Sigang Yang, Xiaojian Wang, Chen Jin, Donghui Jin, Hongwei Chen, Minghua Chen, Shizhong Xie，Optical generation of Terahertz based on all fiber highly coherent optical parametric light source， 40th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz 2015), H3A3.
[2] Zhaohui Wu,Sigang Yang, Xiaojian Wang, Minghua Chen,Hongwei Chen, Shizhong Xie, Widely Tunable Narrowband Terahertz Source Based on Difference Frequency Generation from Parameter Light Source, Asia Communications and Photonics Conference (ACP) 2015, ASu3C.2.
[3] Chen Jin,Sigang Yang, Xiaojian Wang, Minghua Chen,Hongwei Chen, Shizhong Xie, Stable Nanosecond Chirp-free Pulse Generation with Ultra-narrow Bandwidth from a Passively CW Mode-locked Fiber Laser, Asia Communications and Photonics Conference (ACP) 2015, AM3B.5.
[4] Lei Zhang&, Sigang Yang*, Hongwei Chen, Minghua Chen, and Shizhong Xie, Broadly time-dispersion-tuned narrow linewidth all-fiber-integrated optical parametric oscillator, Optical Fiber Communication Conference, OFC: 2014, W4E.2.
[5] Lei Zhang&, Sigang Yang*, Hongwei Chen, Minghua Chen, and Shizhong Xie, Ultraviolet-shift supercontinuum generation by cross-phase modulation in photonic crystal fiber，2013 Conference on Lasers and Electro-Optics: Laser Science to Photonic Applications, CLEO: 2013, JW2A.13.
[6] Lei Zhang&, Sigang Yang*, Hongwei Chen, Minghua Chen, and Shizhong Xie, Wavelength-tunable red-shift Cherenkov radiation in photonic crystal fibers for mid-infrared wavelength generation, 18th Opto-Electronics and Communications Conference, OECC: 2013, WS4-4.
[7] Doudou Gou&, Sigang Yang*, Lei Zhang, Xiaojian Wang, Hongwei Chen, Shizhong Xie, Theoretical design and experimental demonstration of photonic crystal fibers operating for parametric generation near 1.06 um, Asia Communications and Photonics Conference. ACP, 2013.
[8] Doudou Gou&, Sigang Yang*,Feifei Yin, Lei Zhang, Xiaojian Wang, Hongwei Chen, Shizhong Xie, SESAM-based ring-cavity all-normal-dispersion tunable ytterbium mode-locked fiber laser, 18th Opto-Electronics and Communications Conference, OECC: 2013.
[9] Xiaojian Wang&, Sigang Yang*, Lei Zhang, Hongwei Chen, Minghua Chen, Shizhong Xie, Theoretical modeling and experimental verification of optical parametric amplifier based on photonic crystal fiber at 1 um band, Asia Communications and Photonics Conference. ACP, 2013.
[10] Sigang Yang, Qin Li, K.S. Lui, and Kenneth K. Y. Wong, FM Mode-Locked Fiber Optical Parametric Oscillator, 37th European Conference on Optical Communication (ECOC). 2011. We.10.P1.04.
[11]Sigang Yang, Chi Zhang, Yue Zhou, and Kenneth K. Y. Wong, “Photonic Generation of Square Waveform Based on Fiber Optical Parametric Oscillator,”  paper JTuD82, 2010 Conference on Lasers and Electro Optics/ Quantum Electronics and Laser Science Conference (CLEO/QELC), San Jose, California, USA (May 2010).
[12] Sigang Yang, Kim K. Y. Cheung, Xing Xu, Yue Zhou, and Kenneth K. Y. Wong, “Tunable Single-Longitudinal-Mode Fiber Optical Parametric Oscillator with Saturable-Absorber-Based Auto-Tracking Filter,” paper JWA16, 2010 Optical Fiber Communication Conference (OFC), San Diego, California, USA (March 2010).
[13] Sigang Yang; Jia Li; Yue Zhou; Wong, K.K.Y, “Actively mode-locked fiber optical parametric oscillator,” paper JWA12, 2009 Optical Fiber Communication Conference (OFC), San Diego, California, USA (March 2009).
[14]Sigang Yang, Yu Liang, Xing Xu, Kenneth K. Y. Wong, “Single-Longitudinal-Mode Continuous-Wave Fiber Optical Parametric Oscillator,” paper 7.1.3, 35nd European Conf. on Optical Communications (ECOC), Vienna, Austria(Sept. 2009).
[15]Sigang Yang, Xing Xu, and Kenneth K. Y. Wong, “Low threshold, dual-cavity continuous-wave fiber optical parametric oscillator,” paper TuA7, 14th OptoElectronics and Communications Conference (OECC), Hong Kong, China (2009).
[16] Sigang Yang, Yejin Zhang, Lina He, Shizhong Xie. “Experimental demonstration of very high negative chromatic dispersion dual-core photonic crystal fiber,” paper OThA6, 2007 Optical Fiber Communication Conference (OFC), Anaheim, California, USA (March 2007).
[17] Sigang Yang, Yejin Zhang, Shizhong Xie. “Transformation of a single mode photonic crystal fiber into a tunable dispersion compensator,” paper We3.P.1, 32nd European Conference on Optical Communication(ECOC), Cannes, France (Sept.2006).
[18] Sigang Yang, Yejin Zhang, Shizhong Xie. “Tunable Optical Filter Employing a Novel Quartz Cavity Etalon by Precise Angle Tuning,” 2006 Asia-Pacific Optical Communication Conference (APOC), Gwangju, South Jeolla, South Korea (2006).
[19] Sigang Yang,Yejin Zhang,Xiaozhou Peng,Xiangfei Chen,Shizhong Xie. “Analysis and evaluation of the effect of fabrication-related structure fluctuations on the loss of photonic crystal fibers,” 2004 Asia-Pacific Optical Communication Conference (APOC), Beijing, China (Nov. 2004).