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arXiv · 1802.01409

Spatial control of carrier capture in two-dimensional materials: Beyond energy selection rules

Roberto Rosati·Frank Lengers·Doris E. Reiter·Tilmann Kuhn
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Abstract

Transition metal dichalcogenide monolayers have attracted wide attention due to their remarkable optical, electronic and mechanical properties. In these materials local strain distributions effectively form quasi zero-dimensional potentials, whose localized states may be populated by carrier capture from the continuum states. Using a recently developed Lindblad single-particle approach, here we study the phonon-induced carrier capture in a MoSe$_2$ monolayer. Although one decisive control parameter is the energy selection rule, which links the energy of the incoming carriers to that of the final state via the emitted phonon, we show that additionally the spatio-temporal dynamics plays a crucial role. By varying the direction of the incoming carriers with respect to the orientation of the localized potential, we introduce a new control mechanism for the carrier capture: the spatial control.

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Roberto Rosati, Frank Lengers, Doris E. Reiter, Tilmann Kuhn. 2018-02-05. Spatial control of carrier capture in two-dimensional materials: Beyond energy selection rules. https://doi.org/10.1103/physrevb.98.195411

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