Share Email Print
cover

Proceedings Paper

Optically pumped stimulated emission in ZnO/ZnMgO multiple quantum wells prepared by combinatorial techniques
Author(s): Handong Sun; Takayuki Makino; Tien Tuan Nguyen; Yusaburo Segawa; ZiKang Tang; George K.L. Wong; Masashi Kawasaki; Akira Ohtomo; Kentaro Tamura; Hideomi Koinuma
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

High quality ZnO/Zn1MgO multi-quantum wells (MQWs) have been prepared on lattice-matched ScAIMgO4 substrates by laser-MBE method. Nine pixels of MQWs having different well widths were integrated in the same substrate by means of combinatorial masking techniques, which provided excellent specimens to systematically study the dependence of physical properties of MQWs on well widths. Optically pumped stimulated emission spectra were measured in these ZnO/Zn1MgO multi-quantum wells by using a tunable pulsed dye laser as excitation source. We investigated the pump-intensity dependence of the stimulated emission spectra from 5 to 300 K. At low temperatures, only one peak in the stimulated emission was observed, which could be assigned to the emission induced by exciton-exciton inelastic scattering (P-band). When the temperature increases above 160 K, there appears an additional peak at the lower energy side of the P-band, which was assigned to electronhole plasma emission. However, the emission due to the exciton-exciton scattering still remains up to room temperature. The gain spectrum for a multi-quantum well sample has been obtained by variable stripe method at room temperature. At an excitation intensity of about 2 MW/cm2, the peak gains for the P-band and electron-hole plasma emission are 239 cm1 and 380 cm1, respectively. The exciton binding energy was deduced from the energy difference between the P-band and free exciton band. The exciton binding energies of these samples having different well widths were found to increase with decreasing the well widths due to the quantum confinement effect. This enhancement of exciton binding energy should be favorable for the stability of exciton states at higher temperatures.

Paper Details

Date Published: 23 April 2001
PDF: 9 pages
Proc. SPIE 4281, Combinatorial and Composition Spread Techniques in Materials and Device Development II, (23 April 2001); doi: 10.1117/12.424747
Show Author Affiliations
Handong Sun, RIKEN-The Institute of Physical and Chemical Research (Japan)
Takayuki Makino, RIKEN-The Institute of Physical and Chemical Research (Japan)
Tien Tuan Nguyen, RIKEN-The Institute of Physical and Chemical Research (Japan)
Yusaburo Segawa, RIKEN-The Institute of Physical and Chemical Research (Japan)
ZiKang Tang, Hong Kong Univ. of Science and Technology (Hong Kong)
George K.L. Wong, Hong Kong Univ. of Science and Technology (Hong Kong)
Masashi Kawasaki, Tokyo Institute of Technology and National Institute for Research in Inorganic Materials (Japan)
Akira Ohtomo, Tokyo Institute of Technology and National Institute for Research in Inorganic Materials (Japan)
Kentaro Tamura, Tokyo Institute of Technology and National Institute for Research in Inorganic Materials (Japan)
Hideomi Koinuma, Japan Science and Technology Corp. and National Institute for Research in Inorganic Materi (Japan)


Published in SPIE Proceedings Vol. 4281:
Combinatorial and Composition Spread Techniques in Materials and Device Development II
Ghassan E. Jabbour; Hideomi Koinuma, Editor(s)

© SPIE. Terms of Use
Back to Top