Accurate measurement of temperature and electrochemical potential of InGaAsP/InP heterostructures: A first indication of hot carriers solar cell operation

We investigated a semiconductor heterostructure based on InGaAsP multi quantum wells using optical and electrical characterizations. The optical analysis allows us to probe the potential of such a structure in the scope of hot carrier solar cell device. Using different photoluminescence techniques, the quasi Fermi level splitting Δμ and the carrier temperature is estimated as a function of the excitation power. Both values are measured at the quantum wells and at the barrier emission energy. High values of Δμ is found as well as high carrier temperature showing the capability of this structure to work as Hot Carrier Solar cell absorber. Δμ measured in the barrier energy region exceeds the minimum absorption threshold. This fact evidences the potential quantum wells structure to overcome the Schockley Queisser limit.