Tailoring the effect of electric field in type II W-design InAs/GaInSb quantum well structures for emission up to 12 μm

• Electronic structure calculations of GaSb-based type II active region of long wavelength interband cascade lasers.
• Study of electric field effect on the optical transitions in long wavelength W-design quantum wells.
• Optimization of the emission wavelength and type II transition intensity for structures emitting in the range up to 12 μm.

In this paper, we present theoretical investigation of the band structure properties of the type-II W-design AlSb/InAs/GaInSb/InAs/AlSb quantum wells predicted for the active region of interband cascade lasers emitting in a broad range of mid infrared. We utilize the multiband k·p theory in order to calculate the dependence of the energy and oscillator strength of the fundamental optical transition on the thickness of particular layers confining electrons and holes, including the external bias to simulate the conditions occurring in an operational device. It is shown that for a given electric field the properly chosen thicknesses of the wells allow optimizing simultaneously the emission wavelength and type II transition intensity for any wavelength up to about 12 μm at least.