Phonon and polariton dynamics and the existence of long-lived acoustic phonons

Walter E. Bron; Tibor Juhasz

doi:10.1117/12.175885

6 May 1994 Phonon and polariton dynamics and the existence of long-lived acoustic phonons

Walter E. Bron, Tibor Juhasz

Proceedings Volume 2142, Ultrafast Phenomena in Semiconductors; (1994) https://doi.org/10.1117/12.175885
Event: OE/LASE '94, 1994, Los Angeles, CA, United States

Abstract

Coherent states of optical phonons and polaritons are created through coherent Raman excitation (CRE) and their dephasing is determined through pico- and femtosecond time resolved coherent anti-Stokes Raman spectroscopy (TRCARS). The temperature dependence of the dephasing is used to identify the acoustic phonons generated from the decay of coherent optical states. The general decay channel involves the decay of the optical phonons and polaritons into two acoustic phonons each with one half the optical phonon energy and with compensating wave vectors. In some cases the decay channel is more complicated. In order to conserve momentum one of the phonons is near the positive X-point and the other near the negative X-point of the Brillouin zone. The TA phonon is on the lowest dispersion branch and, therefore, cannot further decay into lower energy phonons and still obey energy and momentum conservation. Thus to third order in the decay kinetics the TA phonons should have infinite lifetime. Our observations lead to a TA phonon lifetime of 66.5 +/- 5 ns.

Citation Download Citation

Walter E. Bron and Tibor Juhasz "Phonon and polariton dynamics and the existence of long-lived acoustic phonons", Proc. SPIE 2142, Ultrafast Phenomena in Semiconductors, (6 May 1994); https://doi.org/10.1117/12.175885

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available