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.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1151-1157 |
| Number of pages | 7 |
| Journal | Physical Chemistry Chemical Physics |
| Volume | 19 |
| Issue number | 2 |
| DOIs | |
| State | Published - 2017 |
Funding
L. F. acknowledges NSF DGE-0801685 and the Institute for Sustainability and Energy at Northwestern. Use of the Center for Nanoscale Materials was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. Crystal growth was supported by NSF DMR-1307698 and in part by Argonne National Laboratory under U.S. Department of Energy contract DE-AC36-08GO28308. We acknowledge the X-ray and OMM Facilities at the MRC of Northwestern, which are supported by NSF MRSEC program DMR-1121262.
ASJC Scopus subject areas
- General Physics and Astronomy
- Physical and Theoretical Chemistry
