Strain induced exciton fine-structure splitting and shift in bent ZnO microwires.
Lattice strain is a useful and economic way to tune the device performance and is commonly present in nanostructures. Here, we investigated for the first time the exciton spectra evolution in bent ZnO microwires along the radial direction via high spatial/energy resolution cathodeluminescence spectroscopy at 5.5 K. Our experiments show that the exciton peak splits into multi fine peaks towards the compressive part while retains one peak in the tensile part and the emission peak displays a continuous blue-shift from tensile to compressive edges. In combination with first-principles calculations, we show that the observed NBE emission splitting is due to the valence band splitting and the absence of peak splitting in the tensile part maybe due to the highly localized holes in the A band and the carrier density distribution across the microwire. Our studies may pave the way to design nanophotonic and electronic devices using bent ZnO nanowires.
State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871, P.R. China.
Zhi-Min
ZM
Liao
Han-Chun
HC
Wu
Qiang
Q
Fu
Xuewen
X
Fu
Xinli
X
Zhu
Jun
J
Xu
Igor V
IV
Shvets
Zhuhua
Z
Zhang
Wanlin
W
Guo
Yamin
Y
Leprince-Wang
Qing
Q
Zhao
Xiaosong
X
Wu
Da-Peng
DP
Yu
D003198:Computer Simulation; D005456:Fluorescent Dyes / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D053770:Nanowires / Q000737:chemistry* / Q000648:ultrastructure; D009930:Organic Chemicals / Q000737:chemistry; D010316:Particle Size; D013050:Spectrometry, Fluorescence; D013314:Stress, Mechanical; D013696:Temperature; D013816:Thermodynamics; D015034:Zinc Oxide / Q000737:chemistry*
D005456:Fluorescent Dyes; D009930:Organic Chemicals; C057718:6-(Dimethylamino)-2-((1E,3E)-4-(4-(dimethylamino)phenyl)-1,3-butadien-1-yl)-1-ethylquinolinium perchlorate; D015034:Zinc Oxide