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arXiv · 1201.3333

Enlarged magnetic focusing radius of photoinduced ballistic currents

Markus Stallhofer·Christoph Kastl·Marcel Brändlein·Dieter Schuh·Werner Wegscheider·Jörg. P. Kotthaus·Gerhard Abstreiter·Alexander Holleitner
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Abstract

We exploit GaAs-based quantum point contacts as mesoscopic detectors to analyze the ballistic flow of photogenerated electrons in a two-dimensional electron gas at a perpendicular magnetic field. Whereas charge transport experiments always measure the classical cyclotron radius, we show that this changes dramatically when detecting the photoinduced non-equilibrium current in magnetic fields. The experimentally determined radius of the trajectories surprisingly exceeds the classical cyclotron value by far. Monte Carlo simulations suggest electron-electron scattering as the underlying reason.

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Markus Stallhofer, Christoph Kastl, Marcel Brändlein, Dieter Schuh, Werner Wegscheider, Jörg. P. Kotthaus, Gerhard Abstreiter, Alexander Holleitner. 2012-01-16. Enlarged magnetic focusing radius of photoinduced ballistic currents. https://doi.org/10.1103/physrevb.86.115315

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