Perpendicular transport of photoexcited carriers influenced by heterointerface disorder in GaAs/AlAs superlattices

Author

Yamada, M. ; Yamamoto, Y. ; Ikemoto, T. ; Nogami, T. ; Fujiwara, K.

Author_Institution

Kyushu Inst. of Technol., Kitakyushu, Japan

fYear

2000

fDate

2000

Firstpage

248

Lastpage

251

Abstract

Perpendicular tunneling transport of photoexcited carriers sinking into an intentionally enlarged GaAs single quantum well (SQW) in GaAs/AlAs short-period superlattices (SPS) is investigated as a function of lattice temperature (T) by steady-state and time-resolved photoluminescence (TR-PL) experiments. By measuring PL signals from SPS as well as from SQW to monitor the transport efficiency, it is found that, while a weak ambipolar tunneling-assisted hopping conduction prevails at lower T via localized states formed due to heterointerface disorder within the SPS layer, the Bloch-type transport is observed due to thermal activation of photoexcited carriers to the extended miniband states at T>30 K. This temperature evolution of the perpendicular transport is directly evidence by TR-PL measurements and rigorously explained by a rate equation analysis

Keywords

III-V semiconductors; aluminium compounds; gallium arsenide; hopping conduction; interface states; photoconductivity; photoluminescence; semiconductor quantum wells; semiconductor superlattices; time resolved spectra; tunnelling; 30 K; Bloch-type transport; GaAs-AlAs; GaAs/AlAs short-period superlattices; GaAs/AlAs superlattices; PL signals; enlarged GaAs single quantum well; extended miniband states; heterointerface disorder; lattice temperature; localized states; perpendicular transport; photoexcited carriers; rate equation analysis; steady-state photoluminescence; temperature evolution; thermal activation; time-resolved photoluminescence; tunneling transport; weak ambipolar tunneling-assisted hopping conduction; Equations; Gallium arsenide; Lattices; Monitoring; Photoluminescence; Steady-state; Superlattices; Temperature; Thermal conductivity; Tunneling;

fLanguage

English

Publisher

ieee

Conference_Titel

Semiconducting and Insulating Materials Conference, 2000. SIMC-XI. International

Conference_Location

Canberra, ACT

Print_ISBN

0-7803-5814-7

Type

conf

DOI

10.1109/SIM.2000.939237

Filename

939237