Terahertz wave generation via difference frequency mixing under nearly resonant exciton excitation with 1.5 μm band laser light in GaSb/AlGaSb multiple quantum wells

Abstract Direct conversion of 1.5 μm band light to terahertz wave is significant for ultrafast telecommunication and safer spectroscopy. This study reports generating terahertz waves via difference frequency mixing by exciting strained semiconductor quantum wells with a 1.5 μm band laser emitting two wavelengths. The excitation power dependence demonstrates a clear square dependence of the intensity, and the well-width dependence suggests the possibility creating nonlinear polarization by localized excitons.