서지주요정보
수직공진 표면광 레이저의 자발방출 특성과 미세공진기 효과에 관한 연구 = Spontaneous emission characteristics and microcavity effects of vertical-cavity surface-emitting lasers
서명 / 저자 수직공진 표면광 레이저의 자발방출 특성과 미세공진기 효과에 관한 연구 = Spontaneous emission characteristics and microcavity effects of vertical-cavity surface-emitting lasers / 신재헌.
저자명 신재헌 ; Shin, Jae-Heon
발행사항 [대전 : 한국과학기술원, 1997].
Online Access 원문보기 원문인쇄

소장정보

등록번호

8008112

소장위치/청구기호

학술문화관(문화관) 보존서고

DPH 97027

SMS전송

도서상태

이용가능

대출가능

반납예정일

초록정보

The lateral spontaneous emission intensities of 850-nm proton-implanted and 780-nm oxidized vertical-cavity surface-emitting lasers(VCSEL) were measured and characterized. The spontaneous emission intensity was not proportional to the injected current in the low current range below threshold showing the effect of nonradiative recombinations. A simple phenomenological relation between the spontaneous emission and the current was modeled and used to fit the measured data. The extracted nonradiative recombination coefficients ($A_{nr}'s$) through the fitting process are $2.5 \times 10^8$, $1.7 \times 10^8$, $1.3 \times 10^{8} s^{-1}$ for the 10, 15, and 20-㎛ proton- implanted VCSELs, respectively. The larger value of $A_{nr}$ for the smaller device is related to the induced damages from the proton implantation. Very small 780-nm VCSELs ranging 2 to 10 ㎛ were fabricated by selective oxidation. The below-threshold spontaneous emission intensities were measured in lateral direction. The spontaneous emission intensity was not proportional to the injected current in the low current range showing the effect of carrier diffusion as well as nonradiative recombination. A simplified below-threshold diffusion equation with $A_{nr}$ as a parameter was modeled and used to fit the measured data. It turns out that the ambipolar diffusion coefficient of 5.4㎠/s gives almost same values of $A_{nr}$ regardless of device sizes. Therefore, in the assumption of size-independent $A_{nr}$, the diffusion coefficient of 5.4㎠/s and the nonradiative recombination coefficient of $0.79 \times 10^8s^{-1}$ were obtained experimentally. Further analysis through the diffusion equation shows that there exists a certain optical loss increasing the threshold current significantly for the sizes less than 4 ㎛. It might be the optical scattering at the edge of oxidized layer. The spontaneous emission factors (β's) were measured for the very small 780-nm oxidized VCSELs. To extract β, a new experimental method was proposed and demonstrated. The proposed method uses the below-threshold power and linewidth of the fundamental mode. The experimentally determined β's were $1.33 \times 10^{-3}$, $1.00 \times 10^{-3}$, $6.32 \times 10^{-4}$ for the 2, 3, 4-㎛ oxidized VCSELs, respectively. The somewhat small value of 2-㎛ VCSEL is due to the carrier diffusion. The measured β's agree well with theoretical values within ±30% if the effect of carrier diffusion is considered. It is pointed that the effect of carrier diffusion would reduce the β significantly for sub-㎛ oxidized VCSELs.

서지기타정보

서지기타정보
청구기호 {DPH 97027
형태사항 v, 104 p. : 삽도 ; 25 cm
언어 한국어
일반주기 저자명의 영문표기 : Jae-Heon Shin
지도교수의 한글표기 : 이용희
지도교수의 영문표기 : Yong-Hee Lee
수록잡지명 : "Spontaneous emission factor of oxidized vertical-cavity surface-emitting lasers from the measured below-threshold cavity loss". Applied Physics Letters. American Institute of Physics, vol. 70, no. 18, pp. 2344-2346 (1997)
수록잡지명 : "Effect of carrier diffusion in oxidized vertical-cavity surface-emitting lasers determined from lateral spontaneous emission". Applied Physics Letters. American Institute of Physics, vol. 70, no. 20, pp. 2652-2654 (1997)
학위논문 학위논문(박사) - 한국과학기술원 : 물리학과,
서지주기 참고문헌 : p. 90-104
주제 수직공진 표면광 레이저
비발광결합
운반자확산
자발방출인수
VCSEL
Nonradiative recombination
Carrier diffusion
Spontaneous emission factor
QR CODE qr code