Intracavity sum-frequency generation in GaAs quantum cascade lasers

Abstract

Emission of coherent light at 5.75 μm wavelength has been obtained by intracavity frequency doubling of a GaAs-based quantum cascade laser. This nonlinearity originates from the second-order susceptibility of the bulk material hosting the heterostructure and can be exploited by growing the quantum cascade laser on a 〈111〉 substrate.