Analytical solution of the rate equation in direct modulation of semiconductor laser

Faculty of Physics, College of Science, Vietnam National University, 334 Nguyen Trai, Thanh Xuan, Hanoi,Viet Nam Abstract: We studied the rate equations of a semiconductor laser operating in a direct modulation mode forthe purpose of obtaining the direct dependence of output photon density on modulating current. We showthat the system of differential equations may be reduced to a special case when the spontaneous carrierdecay rate is equal to the photon decay rate. The unique solution is obtained for this case. We also show thata laser operating in direct modulation exhibits an inertia in switching between the optical and electricalfields which introduces a corresponding loss in the modulating current. The output photon density and theinput carrier density depend directly on this loss. For the systems with a minimal and maximal loss, theoutput photon density can be obtained analytically. ?? 2008 IEEE. Index Keywords: Decay (organic); Electric conductivity; Heterojunctions; Lasers; Modulation; Photons;Semiconductor materials; Analytical solutions; Carrier decays; Carrier densities; Direct modulations;Electrical fields; Photon decays; Photon densities; Rate equations; System of differential equations;Semiconductor lasers Year: 2008 Source title: Proceedings - 2008 International Conference on Advanced Technologies for Communications,ATC 2008, Held in Conjunction with REV Meeting Art. No.: 4760600 Page : 371-375 Link: Scorpus Link Correspondence Address: Nhat, H. N.; Faculty of Physics, College of Science, Vietnam National University,334 Nguyen Trai, Thanh Xuan, Hanoi, Viet Nam; email: namnhat@gmail.com Conference name: 2008 International Conference on Advanced Technologies for Communications, ATC2008 Conference date: 6 October 2008 through 9 October 2008 Conference location: Hanoi Conference code: 75765 ISBN: 9.78E+12 DOI: 10.1109/ATC.2008.4760600 Language of Original Document: English Abbreviated Source Title: Proceedings - 2008 International Conference on Advanced Technologies forCommunications, ATC 2008, Held in Conjunction with REV Meeting Document Type: Conference Paper Source: Scopus