Determination of photo-induced Seebeck coefficient for hot carrier solar cell applications

Determination of Seebeck coefficient is a practical technique to investigate the direct conversion of hot carrier energy to electric voltage. However, this study is challenging, especially in nanostructured materials using traditional measurements via heaters and electric contacts. Here, we investigate photo-induced Seebeck effects of InGaAs multi-quantum-well structure via a contact-less measurement (photoluminescence spectroscopy). We have determined thermodynamic properties of hot carriers via fitting the emitted photoluminescence spectra with the generalized Planck's law. We have observed a linear dependence between the gradient of carrier temperature and the quasi-Fermi level splitting of photo-generated hot carriers at various lattice temperatures, which is associated with thermoelectric effects in the system.