Two-dimensional Fourier Transform Studies of Excitons in Layered Indium Selenide

Indium selenide (InSe) is a layered semiconducting material whose electronic properties are strongly influenced by many-body interactions. Having potential applications including optoelectronic and photovoltaic uses, it is necessary to understand the nature of these interactions in order to understand the material properties of interest. Three-pulse four-wave mixing (FWM) and Two-dimensional Fourier transform (2DFT) spectroscopy are used to study the many-body interactions in $\gamma $-InSe by measuring excitonic dephasing and lifetime. Excitation-density-dependent and temperature-dependent measurements of the homogeneous linewidth indicate strong contributions of exciton-exciton scattering and exciton-phonon interactions.