Source: NANOTECHNOLOGY Volume: 24 Issue: 33 Article Number: 335501 DOI: 10.1088/0957-4484/24/33/335501 Published: AUG 23 2013
Times Cited in Web of Science: 0
Total Times Cited: 0
Abstract: Ag nanoparticles (NPs) coated with silica nanolayers were decorated onto a large-scale and uniform silicon nanowire array (SiNWA) by simple chemical etching and metal reduction processes. The three-dimensional Ag/SiNWAs thus formed are employed as a substrate for surface-enhanced Raman scattering (SERS), and a detection limit for rhodamine 6G as low as 10(-16) M and a Raman enhancement factor as large as 10(14) were obtained. Simulation results show that two kinds of inter-Ag-NP nanogaps in three-dimensional geometry create a huge number of SERS 'hot spots' where electromagnetic fields are substantially amplified, contributing to the higher SERS sensitivity and lower detection limit. The excellent SERS stability of Ag/SiNWAs is attributed to the presence of the SiO2 nanolayer around Ag NPs that prevented the Ag NP surface from being oxidized. The calibration of the Raman peak intensities of rhodamine 6G and thiram allowed their quantitative detection. Our finding is a significant advance in developing SERS substrates for the fast and quantitative detection of trace organic molecules.
Addresses: [Zhang, Chang Xing; Su, Lei; Chan, Yu Fei; Xu, Hai Jun; Sun, Xiao Ming] Beijing Univ Chem Technol, State Key Lab Chem Resource Engn, Beijing 100029, Peoples R China.
[Zhang, Chang Xing; Su, Lei; Chan, Yu Fei; Xu, Hai Jun; Sun, Xiao Ming] Beijing Univ Chem Technol, Sch Sci, Beijing 100029, Peoples R China.
[Wu, Zheng Long] Beijing Normal Univ, Analyt & Testing Ctr, Beijing 100875, Peoples R China.
[Zhao, Yong Mei] Chinese Acad Sci, Inst Semicond, Engn Res Ctr Semicond Integrated Technol, Beijing 100083, Peoples R China.
Reprint Address: Zhang, CX (reprint author), Beijing Univ Chem Technol, State Key Lab Chem Resource Engn, Beijing 100029, Peoples R China.
E-mail Addresses: hjxu@mail.buct.edu.cn
ISSN: 0957-4484
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Record 138 of 495
Title: Design of a silicon Mach-Zehnder modulator with a U-type PN junction
Author(s): Cao, TT (Cao, Tongtong); Fei, YH (Fei, Yonghao); Zhang, LB (Zhang, Libin); Cao, YM (Cao, Yanmei); Chen, SW (Chen, Shaowu)
Source: APPLIED OPTICS Volume: 52 Issue: 24 Pages: 5941-5948 DOI: 10.1364/AO.52.005941 Published: AUG 20 2013
Times Cited in Web of Science: 0
Total Times Cited: 0
Abstract: We have developed a silicon depletion-mode modulator featuring a novel U-type PN junction that enables a substantial improvement in electro-optical modulation efficiency. Through electrical, optical, and manufacturing process simulations, an ultralow V pi L of 0.63 V . cm is exhibited with 3 V reverse bias. The high modulation efficiency enables a high extinction ratio (ER) of >17 dB with only a 1 mm phase shifter when the excess loss at the "on" state is 2 dB. The ER can maintain >12 dB at similar to 28 GHz operation with a 3 V peak-to-peak voltage due to the small voltage attenuation of the short phase shifter. (C) 2013 Optical Society of America
Addresses: [Cao, Tongtong; Fei, Yonghao; Zhang, Libin; Cao, Yanmei; Chen, Shaowu] Chinese Acad Sci, Inst Semicond, State Key Lab Optoelect, Beijing 100083, Peoples R China.
Reprint Address: Chen, SW (reprint author), Chinese Acad Sci, Inst Semicond, State Key Lab Optoelect, Beijing 100083, Peoples R China.
E-mail Addresses: swchen@semi.ac.cn
ISSN: 1559-128X
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Record 139 of 495
Title: Ge/Si quantum dots thin film solar cells
Author(s): Liu, Z (Liu, Zhi); Zhou, TW (Zhou, Tianwei); Li, LL (Li, Leliang); Zuo, YH (Zuo, Yuhua); He, C (He, Chao); Li, CB (Li, Chuanbo); Xue, CL (Xue, Chunlai); Cheng, BW (Cheng, Buwen); Wang, QM (Wang, Qiming)
Source: APPLIED PHYSICS LETTERS Volume: 103 Issue: 8 Article Number: 082101 DOI: 10.1063/1.4818999 Published: AUG 19 2013
Times Cited in Web of Science: 0
Total Times Cited: 0
Abstract: Thin film p-i-n solar cells (SCs) with 30 bilayers undoped or p-type self-assembled Ge/Si quantum dots (QDs) were fabricated on n(+)-Si(001) substrates by ultrahigh vacuum chemical vapor deposition. Compared with the SCs without Ge QDs, the external quantum efficiency in infrared region and the short-circuit current densities of the SCs with Ge QDs increased. However, their open-circuit voltages and efficiencies decreased. The open circuit voltages of p-type Ge/Si QDs SCs recovered significantly at low temperature, which was due to the suppression of recombination centers and longer carrier lifetime. (C) 2013 AIP Publishing LLC.
Addresses: [Liu, Zhi; Zhou, Tianwei; Li, Leliang; Zuo, Yuhua; He, Chao; Li, Chuanbo; Xue, Chunlai; Cheng, Buwen; Wang, Qiming] Chinese Acad Sci, Inst Semicond, State Key Lab Integrated Optoelect, Beijing 100083, Peoples R China.
Reprint Address: Cheng, BW (reprint author), Chinese Acad Sci, Inst Semicond, State Key Lab Integrated Optoelect, Beijing 100083, Peoples R China.
E-mail Addresses: cbw@semi.ac.cn
ISSN: 0003-6951
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Record 140 of 495
Title: Conjugated molecule doped polyaniline films as buffer layers in organic solar cells
Author(s): Tan, FR (Tan, Furui); Qu, SC (Qu, Shengchun); Zhang, WF (Zhang, Weifeng); Zhang, XW (Zhang, Xingwang); Wang, ZG (Wang, Zhanguo)
Source: SYNTHETIC METALS Volume: 178 Pages: 18-21 DOI: 10.1016/j.synthmet.2013.06.006 Published: AUG 15 2013
Times Cited in Web of Science: 0
Total Times Cited: 0
Abstract: Doping of polyaniline (PANI) is of great importance to tune its properties. In this work, we have prepared doped PANI films with electrochemistry method. A conjugated molecule with short chain length, 9-anthracene methyl acid (AMA), was used as the dopant considering its electrically active conjugated structure. Films morphology of doped and undoped PANI samples was researched. The corresponding changes in optical and electrical properties after AMA doping were also discussed. The organic hybrid solar cells with AMA doped PANI films as the anode buffers demonstrated enhanced photovoltaic performance compared to that without buffer layer and that with undoped PANI films. The application of synthesized PANI films in organic solar cells indicates a promising advantage in the flexible photovoltaic devices. (c) 2013 Elsevier B.V. All rights reserved.
Addresses: [Tan, Furui; Zhang, Weifeng] Henan Univ, Dept Phys & Elect, Key Lab Photovolta Mat, Henan 475004, Peoples R China.
[Tan, Furui; Qu, Shengchun; Zhang, Xingwang; Wang, Zhanguo] Chinese Acad Sci, Inst Semicond, Key Lab Semicond Mat Sci, Beijing 100083, Peoples R China.
Reprint Address: Qu, SC (reprint author), Chinese Acad Sci, Inst Semicond, Key Lab Semicond Mat Sci, POB 912, Beijing 100083, Peoples R China.
E-mail Addresses: 82305052qsc@semi.ac.cn
ISSN: 0379-6779
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Record 141 of 495
Title: Widely tunable dual-mode distributed feedback laser fabricated by selective area growth technology integrated with Ti heaters
Author(s): Zhang, C (Zhang, Can); Liang, S (Liang, Song); Zhu, HL (Zhu, Hongliang); Wang, W (Wang, Wei)
Source: OPTICS LETTERS Volume: 38 Issue: 16 Pages: 3050-3053 DOI: 10.1364/OL.38.003050 Published: AUG 15 2013
Times Cited in Web of Science: 0
Total Times Cited: 0
Abstract: A widely tunable dual-mode distributed feedback (DFB) laser fabricated by selective area growth (SAG) technology integrated with Ti heaters was demonstrated. In the device, an original mode spacing of 4 nm was obtained by the simple SAG technology. Ti thin-film heaters were integrated with a novel procedure, which simplifies the fabrication of such heaters greatly. A large electrical resistance of the heaters is obtained at the same time, resulting in a high wavelength tuning efficiency. An accurate mode spacing as small as 0.34 nm and as large as 8.06 nm is achieved, which corresponds to a wide beat frequency range from 42.2 GHz to 1 THz. The simple fabrication process indicates that it is promising for reducing the cost of dual-mode DFB laser in fabricating self-pulsation lasers and THz generators. (C) 2013 Optical Society of America
Addresses: [Zhang, Can; Liang, Song; Zhu, Hongliang; Wang, Wei] Chinese Acad Sci, Inst Semicond, Key Lab Semicond Mat Sci, Beijing 100083, Peoples R China.
Reprint Address: Zhang, C (reprint author), Chinese Acad Sci, Inst Semicond, Key Lab Semicond Mat Sci, POB 912, Beijing 100083, Peoples R China.
E-mail Addresses: zhangcan537@semi.ac.cn
ISSN: 0146-9592
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Record 142 of 495
Title: All-fiber optical filter with an ultranarrow and rectangular spectral response
Author(s): Zou, XH (Zou, Xihua); Li, M (Li, Ming); Pan, W (Pan, Wei); Yan, LS (Yan, Lianshan); Azana, J (Azana, Jose); Yao, JP (Yao, Jianping)
Source: OPTICS LETTERS Volume: 38 Issue: 16 Pages: 3096-3098 DOI: 10.1364/OL.38.003096 Published: AUG 15 2013
Times Cited in Web of Science: 1
Total Times Cited: 1
Abstract: Optical filters with an ultranarrow and rectangular spectral response are highly desired for high-resolution optical/electrical signal processing. An all-fiber optical filter based on a fiber Bragg grating with a large number of phase shifts is designed and fabricated. The measured spectral response shows a 3 dB bandwidth of 650 MHz and a rectangular shape factor of 0.513 at the 25 dB bandwidth. This is the narrowest rectangular bandpass response ever reported for an all-fiber filter, to the best of our knowledge. The filter has also the intrinsic advantages of an all- fiber implementation. (C) 2013 Optical Society of America
Addresses: [Zou, Xihua; Pan, Wei; Yan, Lianshan] Southwest Jiaotong Univ, Ctr Informat Photon & Commun, Chengdu 610031, Peoples R China.
[Zou, Xihua; Li, Ming; Azana, Jose] INRS EMT, Quebec City, PQ, Canada.
[Zou, Xihua] Sci & Technol Elect Informat Control Lab, Chengdu 610036, Peoples R China.
[Zou, Xihua; Yao, Jianping] Univ Ottawa, Microwave Photon Res Lab, Ottawa, ON K1N 6N5, Canada.
[Li, Ming] Chinese Acad Sci, State Key Lab Integrated Optoelect, Inst Semicond, Beijing, Peoples R China.
Reprint Address: Zou, XH (reprint author), Southwest Jiaotong Univ, Ctr Informat Photon & Commun, Chengdu 610031, Peoples R China.
E-mail Addresses: zouxihua@swjtu.edu.cn
ISSN: 0146-9592
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Record 143 of 495
Title: Functionalization of monolayer MoS2 by substitutional doping: A first-principles study
Author(s): Yue, Q (Yue, Qu); Chang, SL (Chang, Shengli); Qin, SQ (Qin, Shiqiao); Li, JB (Li, Jingbo)
Source: PHYSICS LETTERS A Volume: 377 Issue: 19-20 Pages: 1362-1367 DOI: 10.1016/j.physleta.2013.03.034 Published: AUG 15 2013
Times Cited in Web of Science: 1
Total Times Cited: 1
Abstract: Electron-beam mediated substitutional doping of monolayer MoS2 was recently demonstrated, opening a new way to modify its properties. Using first-principles calculations, the structural, electronic and magnetic properties of monolayer MoS2 doped with nonmetal and transition-metal atoms are investigated. All dopants are strongly bound to the structures, inducing interesting magnetic behaviors. While all H, B, N and F-doped monolayers have magnetic moment of 1.0 mu(B), V, Cr, Mn, Fe and Co-doped ones attain 1.0, 4.0, 3.0, 3.0 and 1.0 mu(B), respectively. Additionally, MoS2 undergoes transition from semiconductor to half-metal in the presence of H, B or Cr doping. (C) 2013 Elsevier B.V. All rights reserved.
Addresses: [Yue, Qu; Chang, Shengli; Qin, Shiqiao] Natl Univ Def Technol, Coll Sci, Changsha 410073, Hunan, Peoples R China.
[Li, Jingbo] Chinese Acad Sci, Inst Semicond, State Key Lab Superlattice & Microstruct, Beijing 100083, Peoples R China.
Reprint Address: Li, JB (reprint author), Chinese Acad Sci, Inst Semicond, State Key Lab Superlattice & Microstruct, Beijing 100083, Peoples R China.
E-mail Addresses: jbli@semi.ac.cn
ISSN: 0375-9601
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Record 144 of 495
Title: Two-band finite difference method for the bandstructure calculation with nonparabolicity effects in quantum cascade lasers
Author(s): Ma, XP (Ma, Xunpeng); Li, KW (Li, Kangwen); Zhang, ZY (Zhang, Zuyin); Hu, HF (Hu, Haifeng); Wang, Q (Wang, Qing); Wei, X (Wei, Xin); Song, GF (Song, Guofeng)
Source: JOURNAL OF APPLIED PHYSICS Volume: 114 Issue: 6 Article Number: 063101 DOI: 10.1063/1.4817795 Published: AUG 14 2013
Times Cited in Web of Science: 0
Total Times Cited: 0
Abstract: We present a two-band finite difference method for the bandstructure calculation of quantum cascade lasers (QCLs) based on the equivalent two-band model of the nonparabolic Schrodinger equation. Particular backward and forward difference forms are employed in the discretization procedure instead of the common central difference form. In comparison with the linearization approach of the nonparabolic Schrodinger equation, the method is as accurate and reliable as the linearization approach, while the velocity of the method is faster and the matrix elements are more concise, therefore making the method more practical for QCLs simulations. (C) 2013 AIP Publishing LLC.
Addresses: [Ma, Xunpeng; Li, Kangwen; Zhang, Zuyin; Hu, Haifeng; Wang, Qing; Wei, Xin; Song, Guofeng] Chinese Acad Sci, Inst Semicond, Beijing 100083, Peoples R China.
Reprint Address: Ma, XP (reprint author), Chinese Acad Sci, Inst Semicond, Beijing 100083, Peoples R China.
E-mail Addresses: sgf@semi.ac.cn
ISSN: 0021-8979
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Record 145 of 495
Title: Spin-based effects and transport properties of a spin-orbit-coupled hexagonal optical lattice
Author(s): Zhu, GB (Zhu, G. -B.); Sun, Q (Sun, Q.); Zhang, YY (Zhang, Y. -Y.); Chan, KS (Chan, K. S.); Liu, WM (Liu, W. -M.); Ji, AC (Ji, A. -C.)
Source: PHYSICAL REVIEW A Volume: 88 Issue: 2 Article Number: 023608 DOI: 10.1103/PhysRevA.88.023608 Published: AUG 13 2013
Times Cited in Web of Science: 1
Total Times Cited: 1
Abstract: We investigate an ultracold Fermi gas in a hexagonal lattice subjected to a strong Rashba spin-orbit coupling (SOC). We focus on the marginal Abelian limit with the strength of SOC kappa = pi/2, where the derived Dirac fermions are spin-1/2 spinors in contrast to the pure hexagonal lattice. We find a double-degeneracy at the center of the Brillouin zone, which is a spin-3/2 Dirac-Weyl fermion that can be represented as two spin-1/2 fermions. While at the corner of the Brillouin zone, there occur another two spin-1/2 fermions. These Dirac spinors display a verity of spin textures beyond the usual topological properties. Furthermore, we investigate the energy spectrum of one- dimensional (1D) zigzag and armchair ribbons, and show that the appearance of a new cone at the center of the Brillouin zone can induce two flat bands in a 1D zigzag ribbon. These unique properties allow us to transport a single spin-1/2 Dirac spinor through the 1D zigzag ribbon with two quasi-two-dimensional leads, where only the spin-up or spin-down freedom of the Dirac spinors can transit through the ribbon.
Addresses: [Zhu, G. -B.; Sun, Q.; Ji, A. -C.] Capital Normal Univ, Dept Phys, Beijing 100048, Peoples R China.
[Zhu, G. -B.; Chan, K. S.] City Univ Hong Kong, Dept Phys & Mat Sci, Kowloon, Hong Kong, Peoples R China.
[Sun, Q.; Liu, W. -M.] Chinese Acad Sci, Inst Phys, Beijing 100190, Peoples R China.
[Zhang, Y. -Y.] Chinese Acad Sci, Inst Semicond, SKLSM, Beijing 100083, Peoples R China.
[Zhang, Y. -Y.] Peking Univ, ICQM, Beijing 100871, Peoples R China.
Reprint Address: Ji, AC (reprint author), Capital Normal Univ, Dept Phys, Beijing 100048, Peoples R China.
E-mail Addresses: andrewjee@sina.com
ISSN: 1050-2947
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Record 146 of 495
Title: Multiple scattering theory for massive Dirac fermions on the topological insulator surface with a strong warping effect
Author(s): Fu, ZG (Fu, Zhen-Guo); Zhang, P (Zhang, Ping); Lin, HQ (Lin, Hai-Qing); Li, SS (Li, Shu-Shen)
Source: PHYSICAL REVIEW B Volume: 88 Issue: 8 Article Number: 085304 DOI: 10.1103/PhysRevB.88.085304 Published: AUG 5 2013
Times Cited in Web of Science: 0
Total Times Cited: 0
Abstract: We theoretically develop a partial-wave method to study multiple scattering of massive Dirac fermions on the surface of topological insulators (TI) with strong warping effect. The cross sections (CS), local density of states (LDOS), and charge current density (CCD) for single-, two-, and three-centered magnetic scattering cases are discussed. We demonstrate that the s-wave approximation is not advisable and convergent for magnetic impurity scattering. Similar to the case of nonmagnetic impurity scattering, a sharp resonance peak at the band edge of the gapped TI is found in the total CS for the magnetic impurity scattering. Furthermore, we show that with increasing the Fermi energy, the power-law decay of LDOS is modified due to the warping effect of the Fermi surface. The CCD patterns are also modified remarkably by the strong warping.
Addresses: [Fu, Zhen-Guo; Zhang, Ping; Lin, Hai-Qing] Beijing Computat Sci Res Ctr, Beijing 100084, Peoples R China.
[Zhang, Ping] Inst Appl Phys & Computat Math, LCP, Beijing 100088, Peoples R China.
[Li, Shu-Shen] Chinese Acad Sci, Inst Semicond, SKLSM, Beijing 100083, Peoples R China.
Reprint Address: Zhang, P (reprint author), Beijing Computat Sci Res Ctr, Beijing 100084, Peoples R China.
E-mail Addresses: zhang_ping@iapcm.ac.cn
ISSN: 1098-0121
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Record 147 of 495
Title: Surface saturation control on the formation of wurtzite polytypes in zinc blende SiC nanofilms grown on Si-(100) substrates
Author(s): Liu, XF (Liu Xing-Fang); Sun, GS (Sun Guo-Sheng); Liu, B (Liu Bin); Yan, GG (Yan Guo-Guo); Guan, M (Guan Min); Zhang, Y (Zhang Yang); Zhang, F (Zhang Feng); Dong, L (Dong Lin); Zheng, L (Zheng Liu); Liu, SB (Liu Sheng-Bei); Tian, LX (Tian Li-Xin); Wang, L (Wang Lei); Zhao, WS (Zhao Wan-Shun); Zeng, YP (Zeng Yi-Ping)
Source: CHINESE PHYSICS B Volume: 22 Issue: 8 Article Number: 086802 DOI: 10.1088/1674-1056/22/8/086802 Published: AUG 2013
Times Cited in Web of Science: 0
Total Times Cited: 0
Abstract: We investigate the formations of wurtzite (WZ) SiC nano polytypes in zinc blende (ZB) SiC nanofilms hetero-grown on Si-(100) substrates via low pressure chemical vapor deposition (LPCVD) by adjusting the Si/C ratio of the introduced precursors. Through SEM, TEM, and Raman characterizations, we find that the nanofilms consist of discrete WZ SiC nano polytypes and ZB SiC polytypes composed of WZ polytypes (WZ + ZB) and disordered ZB SiC polytypes, respectively, according to Si/C ratios of 0.5, 1.5, and 3. We attribute the WZ polytype formation to being due to a kinetic mechanism based on the Si/C surface saturation control.
Addresses: [Liu Xing-Fang; Sun Guo-Sheng; Liu Bin; Yan Guo-Guo; Guan Min; Zhang Yang; Zhang Feng; Dong Lin; Zheng Liu; Liu Sheng-Bei; Tian Li-Xin; Wang Lei; Zhao Wan-Shun; Zeng Yi-Ping] Chinese Acad Sci, Inst Semicond, Key Lab Semicond Mat Sci, Beijing 100083, Peoples R China.
Reprint Address: Liu, XF (reprint author), Chinese Acad Sci, Inst Semicond, Key Lab Semicond Mat Sci, Beijing 100083, Peoples R China.
E-mail Addresses: liuxf@mail.semi.ac.cn
ISSN: 1674-1056
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Record 148 of 495
Title: Photonic Generation of Binary Phase-Coded Microwave Signals With Large Frequency Tunability Using a Dual-Parallel Mach-Zehnder Modulator
Author(s): Li, W (Li, Wei); Wang, LX (Wang, Li Xian); Li, M (Li, Ming); Wang, H (Wang, Hui); Zhu, NH (Zhu, Ning Hua)
Source: IEEE PHOTONICS JOURNAL Volume: 5 Issue: 4 Article Number: 5501507 DOI: 10.1109/JPHOT.2013.2274771 Published: AUG 2013
Times Cited in Web of Science: 1
Total Times Cited: 1
Abstract: We present a photonic approach to generating binary phase-coded microwave signals with large frequency tunability using a dual-parallel Mach-Zehnder modulator (DPMZM). The DPMZM consists of a pair of sub-MZMs embedded in the two arms of a parent MZM. In our scheme, one of the sub-MZMs is fed by a sinusoidal microwave signal to be phase-coded, and the other sub-MZM is driven by a rectangular coding signal. The optical signals from the two sub-MZMs are destructively interfered by adjusting the dc bias of the parent MZM. As a result, the optical carrier is binary phase coded. A binary phase-coded microwave signal is generated by beating between the optical carrier and the sidebands. The carrier frequency of the phase-coded microwave signal is widely tunable. Phase-coded microwave signals with two different frequencies at 10 and 20 GHz are experimentally generated, respectively.
Addresses: [Li, Wei; Wang, Li Xian; Li, Ming; Wang, Hui; Zhu, Ning Hua] Chinese Acad Sci, Inst Semicond, State Key Lab Integrated Optoelect, Beijing 100083, Peoples R China.
Reprint Address: Zhu, NH (reprint author), Chinese Acad Sci, Inst Semicond, State Key Lab Integrated Optoelect, Beijing 100083, Peoples R China.
E-mail Addresses: nhzhu@semi.ac.cn
ISSN: 1943-0655
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Record 149 of 495
Title: All-Optical Microwave Photonic Single-Passband Filter Based on Polarization Control Through Stimulated Brillouin Scattering
Author(s): Li, W (Li, Wei); Wang, LX (Wang, Li Xian); Zhu, NH (Zhu, Ning Hua)
Source: IEEE PHOTONICS JOURNAL Volume: 5 Issue: 4 Article Number: 5501411 DOI: 10.1109/JPHOT.2013.2271716 Published: AUG 2013
Times Cited in Web of Science: 0
Total Times Cited: 0
Abstract: We present a novel microwave photonic single-passband filter based on polarization control through simulated Brillouin scattering (SBS). The principle of the filter is based on a vector SBS process, which is different from the previously reported scalar SBS technique. For a radio-frequency (RF) modulated signal launched to the proposed processor, the state of polarization (SOP) of the optical carrier is rotated by 90 degrees through a two-step SBS process. As a result, the RF signals cannot be recovered in the photodetector (PD). To recover the desirable RF signal, the SOP of the RF modulated sideband is rotated by another pump wave. Since the orthogonal polarization condition between the optical carrier and the sideband is destroyed, the desirable RF signal can be recovered. By adjusting the wavelength of the pump wave, the frequency response of the filter is tunable in a frequency range from similar to 2 to 20 GHz with out-of-band rejection of similar to 30 dB and similar to 3 dB bandwidth of similar to 20 MHz. In addition, for any modulation format, it is converted to the single-sideband (SSB) modulation by the proposed filter. Therefore, the system is expected to be immune to the fiber dispersion-induced power fading. Moreover, it is independent of the modulation formats of the incoming signal wave. The filter structure can be inserted anywhere in conventional fiber-optic links without the need for modifying the link configuration and the transmitter. |