Enhanced modulation bandwidth (20 GHz) of In/sub 0.4/Ga/sub 0.6/As-GaAs self-organized quantum-dot lasers at cryogenic temperatures: role of carrier relaxation and differential gain

Author

Klotzkin, David ; Kamath, Kishore ; Vineberg, Karen ; Bhattacharya, Pallab ; Murty, Ramana ; Laskar, Joy

Author_Institution

Dept. of Electr. Eng. & Comput. Sci., Michigan Univ., Ann Arbor, MI, USA

Volume

10

Issue

7

fYear

1998

fDate

7/1/1998 12:00:00 AM

Firstpage

932

Lastpage

934

Abstract

Measurements of the threshold current, slope efficiency and optical modulation characteristics of self-assembled InGaAs-GaAs quantum-dot lasers have been made in the temperature range of 20-200 K in order to understand the carrier dynamics in these devices. The dc characteristics of these devices showed a region of almost temperature independent threshold current up to 85 K (T/sub 0/=670 K) with a maximum slope efficiency at 150 K. The maximum measured bandwidth increased from 5 GHz at room temperature to 20 GHz at 80 K. This is consistent with the bandwidth being limited by carrier relaxation time through electron-hole scattering.

Keywords

III-V semiconductors; carrier relaxation time; cryogenics; electro-optical modulation; gallium arsenide; indium compounds; quantum well lasers; self-adjusting systems; semiconductor quantum dots; 20 GHz; 20 to 200 K; 5 to 20 GHz; 80 K; 85 K; In/sub 0.4/Ga/sub 0.6/As-GaAs; In/sub 0.4/Ga/sub 0.6/As-GaAs self-organized quantum-dot lasers; carrier dynamics; carrier relaxation; carrier relaxation time; cryogenic temperatures; dc characteristics; differential gain; electron-hole scattering; enhanced modulation bandwidth; maximum measured bandwidth; maximum slope efficiency; optical modulation characteristics; room temperature; self-assembled InGaAs-GaAs quantum-dot lasers; slope efficiency; temperature independent threshold current; temperature range; threshold current measurement; Atomic measurements; Bandwidth; Cryogenics; Current measurement; Gain measurement; Optical modulation; Quantum dot lasers; Quantum dots; Temperature distribution; Threshold current;

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/68.681274

Filename

681274