Fig. 5
Effect of strain on the bandgap energy of the core in GaAs/InxAl1−xAs core/shell nanowires with shell thickness LS = 80 nm. a Photoluminescence (PL) spectra as measured on ensembles of nanowires with different x at 12 and 300 K. The spectra have been shifted vertically for the sake of clarity. Fit curves (Voigt) are shown in green (contributing peaks) and red (cumulative curves). Primary (E1) and secondary (E2) emissions are indicated with blue and black arrows, respectively. b E1 peak energy at 12 K (blue data points) as a function of the hydrostatic strain in the core (bottom x-axis) and the corresponding In-content x in the shell (top x-axis). The energy error bars correspond to the full-width at half-maximum of the PL fit curves, whereas the strain error bars originate from the error bars in Raman scattering measurements. The blue dashed line is a linear fit of the PL data. The black lines correspond to the bandgap energy of bulk GaAs as a function of strain, calculated with deformation potential theory (DP; dashed line) or from first-principles (GW; dash-dotted line). c Integrated intensity of the E1 peak in polarisation-resolved PL at 300 K. The polarisation of the excitation light was parallel to the nanowire axis (0° and 180°)
