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arXiv · 2212.05507

Dynamics of the fractional quantum Hall edge probed by stroboscope measurements of trions

Akinori Kamiyama·Masahiro Matsuura·John N. Moore·Takaaki Mano·Naokazu Shibata·Go Yusa
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Abstract

By using observations from pump-probe stroboscopic confocal microscopy and spectroscopy, we demonstrate the dynamics of trions and the fractional quantum Hall edge on the order of $\sim1$ ps. The propagation of the quantum Hall edge state excited by a voltage pulse is detected as a temporal change in reflectance in the downstream edge probed by optical pulses synchronized with the voltage pulse. The temporal resolution of such stroboscopic pump-probe measurements is as fast as the duration time of the probe pulse ($\sim1$ ps). This ultra-fast stroboscope measurement enables us to distinguish between the normal mode of edge excitation, known as the edge magneto-plasmon or charge density wave, and other high-energy non-linear excitations. This is the only experimental method available to study the ultra-fast dynamics of quantum Hall edges, and makes it possible to derive the metric tensor $g_{μν}$ of the $(1+1)=2$-dimensional curved spacetime in quantum universe and black hole analogs implemented in the quantum Hall edge.

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Akinori Kamiyama, Masahiro Matsuura, John N. Moore, Takaaki Mano, Naokazu Shibata, Go Yusa. 2022-12-11. Dynamics of the fractional quantum Hall edge probed by stroboscope measurements of trions. https://arxiv.org/abs/2212.05507

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