Dynamics of strongly degenerate electron-hole plasmas and excitons in single InP nanowires.
Low-temperature time-resolved photoluminescence spectroscopy is used to probe the dynamics of photoexcited carriers in single InP nanowires. At early times after pulsed excitation, the photoluminescence line shape displays a characteristic broadening, consistent with emission from a degenerate, high-density electron-hole plasma. As the electron-hole plasma cools and the carrier density decreases, the emission rapidly converges toward a relatively narrow band consistent with free exciton emission from the InP nanowire. The free excitons in these single InP nanowires exhibit recombination lifetimes closely approaching that measured in a high-quality epilayer, suggesting that in these InP nanowires, electrons and holes are relatively insensitive to surface states. This results in higher quantum efficiencies than other single-nanowire systems as well as significant state-filling and band gap renormalization, which is observed at high electron-hole carrier densities.
Titova
Lyubov V
LV
Department of Physics, University of Cincinnati, Cincinnati, Ohio 45221-0011, USA.
Hoang
Thang Ba
TB
Yarrison-Rice
Jan M
JM
Jackson
Howard E
HE
Kim
Yong
Y
Joyce
Hannah J
HJ
Gao
Qiang
Q
Tan
H Hoe
HH
Jagadish
Chennupati
C
Zhang
Xin
X
Zou
Jin
J
Smith
Leigh M
LM
D004583:Electrons; D007204:Indium / Q000737:chemistry*; D008027:Light; D053768:Metal Nanoparticles / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D036103:Nanotechnology / Q000379:methods*; D010720:Phosphines / Q000737:chemistry*; D012666:Semiconductors; D012825:Silicon / Q000737:chemistry*; D013997:Time Factors
D010720:Phosphines; D007204:Indium; C090882:indium phosphide; D012825:Silicon