Direct measure of strain and electronic structure in GaAs/GaP core-shell nanowires.
Highly strained GaAs/GaP nanowires of excellent optical quality were grown with 50 nm diameter GaAs cores and 25 nm GaP shells. Photoluminescence from these nanowires is observed at energies dramatically shifted from the unstrained GaAs free exciton emission energy by 260 meV. Using Raman scattering, we show that it is possible to separately measure the degree of compressive and shear strain of the GaAs core and show that the Raman response of the GaP shell is consistent with tensile strain. The Raman and photoluminescence measurement are both on good agreement with 8 band k.p calculations. This result opens up new possibilities for engineering the electronic properties of the nanowires for optimal design of one-dimensional nanodevices by controlling the strain of the core and shell by varying the nanowire geometry.
Department of Physics, University of Cincinnati, Cincinnati, Ohio 45221-0011, USA.
Mohammad
M
Montazeri
Melodie
M
Fickenscher
Leigh M
LM
Smith
Howard E
HE
Jackson
Jan
J
Yarrison-Rice
Jung Hyun
JH
Kang
Qiang
Q
Gao
H Hoe
HH
Tan
Chennupati
C
Jagadish
Yanan
Y
Guo
Jin
J
Zou
Mats-Erik
ME
Pistol
Craig E
CE
Pryor
D001152:Arsenicals / Q000737:chemistry*; D055119:Elastic Modulus; D004583:Electrons; D005708:Gallium / Q000737:chemistry*; D008422:Materials Testing / Q000379:methods*; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D010720:Phosphines / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013314:Stress, Mechanical; D013718:Tensile Strength
D001152:Arsenicals; D010720:Phosphines; C043055:gallium arsenide; C485338:gallium phosphide; D005708:Gallium