Freeze-out of difference-phonon modes in ZnTe and its application in detection of THz pulses

Citation
M. Schall et Pu. Jepsen, Freeze-out of difference-phonon modes in ZnTe and its application in detection of THz pulses, APPL PHYS L, 77(18), 2000, pp. 2801-2803
Citations number
11
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
APPLIED PHYSICS LETTERS
ISSN journal
0003-6951 → ACNP
Volume
77
Issue
18
Year of publication
2000
Pages
2801 - 2803
Database
ISI
SICI code
0003-6951(20001030)77:18<2801:FODMIZ>2.0.ZU;2-I
Abstract
Generation by optical rectification and detection by electro-optic sampling of freely propagating subpicosecond electromagnetic pulses (terahertz puls es) in ZnTe is limited by two broad difference-phonon absorption bands in t he spectral region below the transverse optical resonance at 5.32 THz. In t his letter, we show that, at temperatures below 80 K, these difference mode s are frozen out and consequently ZnTe becomes completely transparent withi n our detection bandwidth. We utilize this effect to obtain a three-fold in crease in detection efficiency at frequencies above 3 THz in a thin ZnTe de tector operated at 80 K, compared to the performance at room temperature. ( C) 2000 American Institute of Physics. [S0003-6951(00)02944-2].