Related Experiment Video
Updated: Mar 10, 2026
Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
Seeing the invisible plasma with transient phonons in cuprous oxide
Laszlo Frazer1, Richard D Schaller2, Kelvin B Chang3
1School of Chemistry, UNSW Sydney, NSW 2052, Australia and Department of Chemistry, Temple University, 1901 N. 13th Street, Philadelphia, PA 19122, USA. pccp@laszlofrazer.com.
Abstract:
The emission of phonons from electron-hole plasma is the primary limit on the efficiency of photovoltaic devices operating above the bandgap. In cuprous oxide (Cu2O) there is no luminescence from electron-hole plasma. Therefore, we searched for optical phonons emitted by energetic charge carriers using phonon-to-exciton upconversion transitions. We found 14 meV phonons with a lifetime of 0.916 ± 0.008 ps and 79 meV phonons that are longer lived and overrepresented. It is surprising that the higher energy phonon has a longer lifetime.
