Time-Resolved Photoluminescence Spectroscopy Of The Carrier Dynamics In GaAs/AlxGa1_xAs Quantum Wells

Hans J. Polland; Jurgen Kuhl; Ernst O. Gobel

doi:10.1117/12.947219

22 August 1988 Time-Resolved Photoluminescence Spectroscopy Of The Carrier Dynamics In GaAs/Al_xGa_1-xAs Quantum Wells

Hans J. Polland, Jurgen Kuhl, Ernst O. Gobel

Proceedings Volume 0942, Ultrafast Laser Probe Phenomena in Bulk and Microstructure Semiconductors II; (1988) https://doi.org/10.1117/12.947219
Event: Advances in Semiconductors and Superconductors: Physics and Device Applications, 1988, Newport Beach, CA, United States

Abstract

Picosecond photoluminescence experiments at low temperature (6K) have been employed to study the trapping dynamics of photoexcited carriers in GaAs/AlGaAs single quantum wells for different shapes of the AlxGai_xAs confinement layers. We have obtained the following results by analyzing the spectral and temporal distribution of the photoluminescence after picosecond pulse excitation: Trapping efficiency is ==, 40% for a standard ungraded cladding layer (A10.3G1.7As with constant band gap and 5nm thick wells) but increases to ,-, 60% and 100% for samp es with a spatially parabolic or linear band gap profile of the confinement layers, respectively. Trapping times are appreciably shorter than the luminescence risetime which is between 60ps to 100ps. Thus carrier trapping does not impose severe limitations on the modulation speed of single quantum well devices up to frequencies in the order of 10GHz. Similar results are obtained for a well with a width of 1.2nm. Inhomogeneities in the carrier trapping mechanism due to well width fluctuations are not observed in our samples. In the second part we describe the photoluminescence properties of GaAs/A1,Gai_x As quantum wells (x=0.3) under the influence of electric fields perpendicular to the layers. We observe a drastic red shift and a concomitant strong increase of the electron-hole recombination lifetime for well widths > lOnm due to the quantum-confined Stark effect. At high fields (50-100kV/cm) field ionization due to tunneling leads to a decrease of both the photoluminescence yield and decay time, in accordance with a simple WKB theory

Citation Download Citation

Hans J. Polland, Jurgen Kuhl, and Ernst O. Gobel "Time-Resolved Photoluminescence Spectroscopy Of The Carrier Dynamics In GaAs/Al_xGa_1-xAs Quantum Wells", Proc. SPIE 0942, Ultrafast Laser Probe Phenomena in Bulk and Microstructure Semiconductors II, (22 August 1988); https://doi.org/10.1117/12.947219

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
8 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Quantum wells

Luminescence

Oscillators

Absorption

Picosecond phenomena

Solids

Laser beam diagnostics

Show All Keywords

Keywords/Phrases

Search In:

Publication Years