Lasers: Structures and Properties Prepared based on Semiconductor optoelectronic devices, by P. Bhattacharya
Junction Laser Operation Principles Semiconductor optoelectronic devices, by P. Bhattacharya
Semiconductor optoelectronic devices, by P. Bhattacharya
Semiconductor optoelectronic devices, by P. Bhattacharya
Threshold current density * For linear gain/current relationship, the dependence of Jth on Lc is, p.279 Semiconductor optoelectronic devices, by P. Bhattacharya
Semiconductor optoelectronic devices, by P. Bhattacharya
Laser Properties Minimization of the threshold current Reducing active layer thickness, d Increasing internal quantum efficiency, Increasing the differential gain Reducing the cavity and mirror losses d Semiconductor Optoelectronic Devices pp. 273-274 참조
Laser Properties Characteristic temperature, T0 constant Characteristic temperature, T0 레이저 다이오드의 열 특성 평가를 위하여 최대구동 온도를 측정 온도가 증가함에 따라 Itho는 증가하고, 어느 온도 이상에서는 광 전류의 특성 곡선이 직선 형태에서 곡선 형태로 변화하는 모습을 띤다. 70 ℃를 경계로 하여 기울기의 변화 25 ~ 70 ℃ 영역 : 156 K 70 ~ 100 ℃ 영역 : 73 K 온도 영역에 따라 To 가 다른 값을 가지고 온도가 상승할수록 작은 To 값을 가진다. 광구속 영역과 P 클래드 영역의 작은 전도대 에너지 차이 때문에 누설 전류가 고온에서는 빠르게 증가하기 때문. Ref) 김동환, 장준호, 유태경, 전자공학회, 1998
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Laser Properties External quantum efficiency *The optical power output into the modal volume due to a current J (Jth) , A : Junction area *The power coupled out through the cleaved facets as useful laser output and overcome losses *Differential quantum efficiency is defined as the increase in light output due to an increase in drive current Semiconductor optoelectronic devices, by P. Bhattacharya
Figure 7.8 Light-current characteristics of an etched mesa buried hetero- structure laser at different temperatures (from G. P. Agrawal and N. K. Dutta , Long wavelength Semiconductor Lasers, Ban Nostrand Reinhold , New York, @ 1996. Reprinted by permission of AT&T Bell Laboratories Semiconductor optoelectronic devices, by P. Bhattacharya
7.3 Heterojunction Lasers Semiconductor optoelectronic devices, by P. Bhattacharya
Semiconductor optoelectronic devices, by P. Bhattacharya
Transverse dimension improvement & kink Semiconductor optoelectronic devices, by P. Bhattacharya