Nonlinear Optoelectronics and Anomalous Photovoltaic Effects in Monolayer MoSe2 Crystals
November 27th, 2018 JORGE QUEREDA Univesity of Groningen

Two-dimensional (2D) transition metal dichalcogenides (TMDs) are very attractive materials for optoelectronics at the nanoscale. Their optical bandgap spanning the visible spectrum, as well as their strong optical absorption, and large charge carrier mobilies could find applications in photodetection and light energy harvesting. Further, the lack of inversion symmetry in 2D-TMDs, combined with their particular band structure gives rise to a plethora of nonlinear optical effects, including second harmonic generation, spin- and valley-selective optical absorption and photoluminescence and anomalous photovoltaic effects. In this talk I will discuss different nonlinear optoelectronic processes in encapsulated monolayer MoSe2 phototransistors as well as their potential applications in optoelectronic and spintronic devices. In particular, I will present our recent finding of anomalous photovoltaic effects (i.e. circular photogalvanic and photon drag effects) in monolayer MoSe2, their physical origin and their potential use for spin current injection in hybrid graphene-TMD devices.

Seminar, November 27, 2018, 12:00. ICFO’s Seminar Room

Hosted by Prof. Frank Koppens