Optical and electrical properties of quantum wells with electrically tunable two-dimensional electron density by selective contacts |
| |
| Affiliation: | 1. Information Materials and Device Applications Key Laboratory of Sichuan Provincial Universitssies, Chengdu University of Information Technology, Chengdu 610225, China;2. State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, No. 58, Renmin Avenue, Haikou, Hainan Province 570228, China;3. Key Laboratory of Optoelectronics Information Technology (Tianjin University), Ministry of Education, Institute of Laser & Opto-Electronics, School of Precision Instruments and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China;1. Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, United States;2. Department of Electrical Engineering, Stanford University, United States;1. Institute for Advanced Study, Chengdu University, Chengdu, 610106, PR China;2. Science and Technology on Plasma Dynamics Laboratory, Air Force Engineering University, Xi''an, Shaanxi, 710038, PR China;3. School of Equipment Management and Support, Engineering University of PAP, Xi''an, 710078, PR China;4. Science and Technology on Thermostructural Composite Materials Laboratory, Northwestern Polytechnical University, Xi''an, 710072, PR China;5. School of Aeronautics, Northwestern Polytechnical University, Xi''an, 710072, PR China;1. Department of Electrical and Computer Engineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA;2. Nick Holonyak, Jr. Micro and Nanotechnology Laboratory, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA;3. Department of Materials Science and Engineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA |
| |
| Abstract: | We report on photoluminescence and absorption measurements in type-I hetero n-i-p-i structures. The electron density in the pseudomorphic InGaAs/GaAs quantum wells is tunable between zero and more then 5 · 1012 cm-2. This electrical tuning of the subband filling is achieved by a variable voltage applied between selective n-and p-contacts fabricated by epitaxial shadow mask MBE. One of the advantages of having selective contacts to the n- and p-layers is to get reliable information about the electron density, independent of measured absorption and luminescence spectra. This allows a more rigorous analysis of the data on bandgap renormalization, bandfilling and k∥-conservation. Moreover, the experiments can be performed at low optical power and low carrier temperatures. In the present investigation a bandgap renormalization of -20 meV and a bandfilling induced shift of the absorption edge as large as +50 meV was observed for a sheet electron density of 5 · 1012 cm-2. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
