The uniaxial stress tunable optical gain of InAs nanowires

We calculate the electronic structures and optical gain of InAs nanowires via the eight-band effective-mass $\mathbf{k}?\mathbf{p}$ theory. It is found that there is one peak in TM gain spectra, and the peak value of TM gain spectra is much larger than that of TE gain spectra when the radius R of the nanowires is 3 nm. Meanwhile, as the radius increases, the peak value of TE gain spectra approaches that of TM gain spectra, and more peaks appear in both TM and TE gain spectra. We therefore predict that InAs nanowires with R smaller than 3 nm can be used to emit TM linearly polarized light. We find, however, with R being 6 nm or 10 nm, a tensile or compressive uniaxial stress along the c axis can be used to tune the optical gain of InAs nanowires, and we can obtain TE or TM linearly polarized light. Our calculation points out the possibility for the application of InAs nanowires in the field of infrared linearly polarized lasers.