All-optical switch utilizing intersubband transition in GaN quantum wells

Author

Iizuka, Norio ; Kaneko, Kei ; Suzuki, Nobuo

Author_Institution

Corporate Res. & Dev. Center, Toshiba Corp., Kawasaki

Volume

42

Issue

8

fYear

2006

Firstpage

765

Lastpage

771

Abstract

Intersubband transition (ISBT) in GaN quantum wells (QWs) was investigated from the viewpoint of application to ultrafast all-optical switches. The effect of crystalline quality on the absorption saturation characteristics was examined and reduction of edge dislocations was found to be a crucial factor in decreasing operation energy. Then, the switching performance was investigated for devices with improved crystalline quality. Modulation of signal pulses with a pulse interval of less than 1 ps was confirmed. Another device displayed gate-switch operation with an extinction ratio of greater than 10 dB. Comparison of the absorption recovery process in both devices suggested that the process is strongly affected by the QW structure

Keywords

III-V semiconductors; edge dislocations; gallium compounds; high-speed optical techniques; optical saturable absorption; optical switches; semiconductor quantum wells; wide band gap semiconductors; GaN; GaN quantum wells; absorption recovery; absorption saturation; all-optical switch; displayed gate-switch; edge dislocation; extinction ratio; intersubband transition; signal pulse modulation; Absorption; Communication switching; Crystallization; Extinction ratio; Gallium nitride; Optical fiber communication; Optical polarization; Optical switches; Optical waveguides; Pulse modulation; Gallium nitride; intersubband transition; optical switches; quantum wells;

fLanguage

English

Journal_Title

Quantum Electronics, IEEE Journal of

Publisher

ieee

ISSN

0018-9197

Type

jour

DOI

10.1109/JQE.2006.878189

Filename

1658127