Figure 4.

Tunability of the emission wavelength of wurtzite nanowires. (a) Photoluminescence spectra of WZ Al_xGa_1–xP and GaAs_yP_1–y ternary compound wires, showing the tunability of the emission wavelength. Substitution of Ga by Al induces a blueshift, and substitution of P by As a redshift of the emission. (b) Energy at the emission maxima as a function of the nanowire composition. (c) Radiative lifetimes as a function of the different wurtzite Al_xGa_1–xP and GaAs_yP_1–y compositions (blue data points). The ZB GaP substrate lifetime is at 254 ns (red point). The dotted line at 57% As indicates the direct/indirect transition for zinc blende GaAsP material. All the measurements are performed at 4 K.