Carrier lifetime and mobility enhancement in nearly defect-free core-shell nanowires measured using time-resolved terahertz spectroscopy.
We have used transient terahertz photoconductivity measurements to assess the efficacy of two-temperature growth and core-shell encapsulation techniques on the electronic properties of GaAs nanowires. We demonstrate that two-temperature growth of the GaAs core leads to an almost doubling in charge-carrier mobility and a tripling of carrier lifetime. In addition, overcoating the GaAs core with a larger-bandgap material is shown to reduce the density of surface traps by 82%, thereby enhancing the charge conductivity.
Parkinson
Patrick
P
Clarendon Laboratory, Department of Physics, University of Oxford, Oxford OX1 3PU, United Kingdom.
Joyce
Hannah J
HJ
Gao
Qiang
Q
Tan
Hark Hoe
HH
Zhang
Xin
X
Zou
Jin
J
Jagadish
Chennupati
C
Herz
Laura M
LM
Johnston
Michael B
MB
D001152:Arsenicals / Q000737:chemistry*; D004553:Electric Conductivity; D005708:Gallium / Q000737:chemistry*; D008422:Materials Testing; D036103:Nanotechnology / Q000379:methods*; D053770:Nanowires / Q000737:chemistry*; D010316:Particle Size; D010777:Photochemistry; D013499:Surface Properties; D013696:Temperature; D055068:Terahertz Spectroscopy / Q000379:methods*; D013997:Time Factors
D001152:Arsenicals; C043055:gallium arsenide; D005708:Gallium