View article

Ordering in the CuPt structure is known to significantly reduce the band gap of Ga_0.52In_0.48P as well as induce a number of unusual details in its optical properties, including long, excitation‐intensity‐dependent lifetimes and an excitation‐intensity‐dependent emission energy. We report photoluminescence (PL), photoluminescence excitation (PLE), and resonant Raman measurements performed on ordered and disordered Ga_0.52In_0.48P. The dominant high energy emission process at low temperature in disordered Ga_0.52In_0.48P is established to be excitonic, but the exciton trapping energy is not unique. PLE from ordered Ga_0.52In_0.48P shows significant tailing of electronic states into the band gap and a ‘‘band edge’’ which depends on detection energy. The dominant radiative process in ordered Ga_0.52In_0.48P is not excitonic. A large increase in the Stokes shift between the absorption edge (band gap) and …