Picosecond CO2laser-induced self-defocusing in InSb

Author

Sheik-Bahae, Mansoor ; Kwok, Hoi-Sing

Author_Institution

Center for research in electro-optics and lasers, University of Central Florida, Orlando, Fl., USA

Volume

23

Issue

11

fYear

1987

fDate

11/1/1987 12:00:00 AM

Firstpage

1974

Lastpage

1980

Abstract

Self-defocusing of 45 ps CO2laser pulses was observed in InSb at intensities as low as 1 MW/cm². This self-defocusing was caused by the two-photon absorption generated free carriers and the resulting self-phase modulation. In addition to demonstrating spatial beam modulation in this material at 10.6 μm, the present experiment also confirms directly that such a process occurs on a picosecond time scale. This information is important in order to increase the switching speed of infrared optical bistable devices to the picosecond regime. Furthermore, the present self-defocusing experiment also provided an accurate determination of the two-photon absorption coefficient in InSb. The value of 2.5 cm/MW obtained agrees exactly with a previous study. Other applications to continuum and ultrashort pulse generation will also be discussed.

Keywords

Carbon dioxide lasers; Indium materials/devices; Laser-beam focusing; Optical propagation in nonlinear media; Optical propagation, semiconducting media; Optical transient propagation; Free electron lasers; Laser beams; Nonlinear optics; Optical bistability; Optical devices; Optical pulse generation; Optical pulses; Optical refraction; Optical variables control; Ultrafast optics;

fLanguage

English

Journal_Title

Quantum Electronics, IEEE Journal of

Publisher

ieee

ISSN

0018-9197

Type

jour

DOI

10.1109/JQE.1987.1073249

Filename

1073249