Direct evidence of interlevel exciton transitions mediated by single phonons in a semiconductor quantum dot using resonance fluorescence spectroscopy.
Using resonance fluorescence, we investigate how acoustic phonons mediate couplings between multiple electronic levels in a semiconductor quantum dot. We show the first direct evidence of population up-conversion in a single quantum dot, which we attribute to absorption of single acoustic phonons. Moreover, through a rate equation analysis, we find that below 20 K such single-phonon mediated couplings between the exciton ground state and the first excited state are primarily responsible for decoherence of the exciton quantum state.
Flagg
Edward B
EB
Physics Department, University of Texas at Austin, 1 University Station C1600, Austin, Texas 78712, USA. edward.flagg@nist.gov
Robertson
John W
JW
Founta
Sébastien
S
Ma
Wenquan
W
Xiao
Min
M
Salamo
Gregory J
GJ
Shih
Chih-Kang
CK