Ultrafast manipulation of 2D material properties with light
Dr. Álvaro Jiménez-Galán
Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC)
2D material host fascinating electronic properties. Two central examples are non-trivial topology and valley physics. Both are controlled by two fundamental symmetries: time-reversal and spatial inversion. I will show how these two symmetries can be controlled on ultrafast timescales using tailored light fields, allowing coherent manipulation of quantum properties. First, I will show that a trefoil-shaped field can controllably break time-reversal symmetry and transform a hexagonal semiconducting monolayer into a laser-analogue of the topological Haldane model, with the band topology controlled on few-femtosecond timescales. In addition, application of these fields to multi-layer or bulk hexagonal system allows to controllably break their inversion symmetry, which allows to extend ultrafast valley manipulation to inversion symmetric hexagonal materials. Finally, I will show the realization of a room-temperature ultrafast valley switch, operated by a train of polarization- and time-controlled VIS pulses.
Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC)
2D material host fascinating electronic properties. Two central examples are non-trivial topology and valley physics. Both are controlled by two fundamental symmetries: time-reversal and spatial inversion. I will show how these two symmetries can be controlled on ultrafast timescales using tailored light fields, allowing coherent manipulation of quantum properties. First, I will show that a trefoil-shaped field can controllably break time-reversal symmetry and transform a hexagonal semiconducting monolayer into a laser-analogue of the topological Haldane model, with the band topology controlled on few-femtosecond timescales. In addition, application of these fields to multi-layer or bulk hexagonal system allows to controllably break their inversion symmetry, which allows to extend ultrafast valley manipulation to inversion symmetric hexagonal materials. Finally, I will show the realization of a room-temperature ultrafast valley switch, operated by a train of polarization- and time-controlled VIS pulses.
