Terahertz electron-hole recollisions in GaAs/AlGaAs quantum wells: robustness to scattering by optical phonons and thermal fluctuations.
Electron-hole recollisions are induced by resonantly injecting excitons with a near-IR laser at frequency fNIR into quantum wells driven by a 10  kV/cm field oscillating at fTHz=0.57  THz. At T=12  K, up to 18 sidebands are observed at frequencies fsideband=fNIR+2nfTHz, with -8≤2n≤28. Electrons and holes recollide with total kinetic energies up to 57 meV, well above the ELO=36  meV threshold for longitudinal optical (LO) phonon emission. Sidebands with order up to 2n=22 persist up to room temperature. A simple model shows that LO phonon scattering suppresses but does not eliminate sidebands associated with kinetic energies above ELO.
Physics Department, University of California, Santa Barbara, California 93106, USA and Institute for Terahertz Science and Technology, University of California, Santa Barbara, California 93106, USA.
Hunter
H
Banks
Physics Department, University of California, Santa Barbara, California 93106, USA and Institute for Terahertz Science and Technology, University of California, Santa Barbara, California 93106, USA.
Ben
B
Zaks
Department of Physics, The Chinese University of Hong Kong, Hong Kong, China.
Fan
F
Yang
Materials Department, University of California, Santa Barbara, California 93106, USA.
Shawn
S
Mack
Materials Department, University of California, Santa Barbara, California 93106, USA.
Arthur C
AC
Gossard
Department of Physics, The Chinese University of Hong Kong, Hong Kong, China.
Renbao
R
Liu
Physics Department, University of California, Santa Barbara, California 93106, USA and Institute for Terahertz Science and Technology, University of California, Santa Barbara, California 93106, USA.
Mark S
MS
Sherwin