1 research outputs found
Strain Mapping and Raman Spectroscopy of Bent GaP and GaAs Nanowires
Strain engineering
of nanowires (NWs) has been recognized as a
powerful strategy for tuning the optical and electronic properties
of nanoscale semiconductors. Therefore, the characterization of the
strains with nanometer-scale spatial resolution is of great importance
for various promising applications. In the present work, we synthesized
single-crystalline zinc blende phase GaP and GaAs NWs using the chemical
vapor transport method and visualized their bending strains (up to
3%) with high precision using the nanobeam electron diffraction technique.
The strain mapping at all crystallographic axes revealed that (i)
maximum strain exists along the growth direction ([111]) with the
tensile and compressive strains at the outer and inner parts, respectively;
(ii) the opposite strains appeared along the perpendicular direction
([2Ì…11]); and (iii) the tensile strain was larger than the coexisting
compressive strain at all axes. The Raman spectrum collected for individual
bent NWs showed the peak broadening and red shift of the transverse
optical modes that were well-correlated with the strain maps. These
results are consistent with the larger mechanical modulus of GaP than
that of GaAs. Our work provides new insight into the bending strain
of III–V semiconductors, which is of paramount importance in
the performance of flexible or bendable electronics