Stochastic Resonance in Quantum-Well Semiconductor Lasers
WANG Jun1, MA Xiao-Yu1, BAI Yi-Ming2, CAO Li3, WU Da-Jin3
1National Engineering Research Center for Opto-Electronic Devices, Institute of Semiconductors, Chinese Academy of Sciences, PO Box 912, Beijing 100083
2Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, PO Box 912, Beijing 100083
13Department of Physics, Huazhong University of Science and Technology, Wuhan 430074
Stochastic Resonance in Quantum-Well Semiconductor Lasers
WANG Jun1;MA Xiao-Yu1;BAI Yi-Ming2;CAO Li3;WU Da-Jin3
1National Engineering Research Center for Opto-Electronic Devices, Institute of Semiconductors, Chinese Academy of Sciences, PO Box 912, Beijing 100083
2Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, PO Box 912, Beijing 100083
13Department of Physics, Huazhong University of Science and Technology, Wuhan 430074
Abstract： The quantum well (QW) semiconductor lasers have become main optical sources for optical fibre communication systems because of their higher modulation speed, broader modulation bandwidth and better temperature characteristics. In order to improve the quality of direct-modulation by means of the stochastic resonance (SR) mechanism in QW semiconductor lasers, we investigate the behaviour of the SR in direct-modulated QW semiconductor laser systems. Considering the cross-correlated carrier noise and photon noise, we calculate the power spectrum of the photon density and the signal-to-noise ratio (SNR) of the direct-modulated laser system by using the linear approximation method. The results indicate that the SR always appears in the dependence of the SNR on the bias current density, and is strongly affected by the cross-correlation coefficient of the carrier and photon noises, the frequency of modulation signal, and the photon lifetime in the laser cavity.
2006, Vol. 23 
