Joyprokash Chakrabartty

The discovery of the optoelectronic properties in ferroelectric perovskite thin films recently paved the way for the exploration of new approaches for energy conversion including applications in photovoltaics (PV). Without need for an n-p junction, the ferroelectric polarization of such thin films induces a strong internal electric field which can be used to separate photo generated carriers, thus producing a photocurrent. Due to the coexistence of ferroelectricity and magnetic order (i.e. transition metal ions with unpaired d electrons) in the same phase, recently epitaxial multiferroic thin films become interesting materials for PV applications since they usually have strong unidirectional ferroelectric polarizations and smaller band gaps (typically ~1.7-2.7eV) compared to conventional ferroelectric materials (~3.5 eV). Currently I am investigating functional properties of multiferroic hetero-epitaxial (single or multi layer) thin films deposited onto substrates by pulse laser deposition (PLD) in order to enhance the power conversion efficiency under solar spectrum (AM 1.5G).