Real-time and -space visualization of excitations of the ν= 1/3 fractional quantum Hall edge

Abstract

We present scanning optical stroboscopic confocal microscopy and spectroscopy measurements wherein three degrees of freedom, namely energy, real-space, and real-time, are resolvable. The edge-state propagation is detected as a temporal change in the optical response in the downstream edge. We succeeded in visualizing the excited states of the most fundamental fractional quantum Hall (FQH) state and the collective excitations near the edge. The results verify the current understanding of the edge excitation and also point toward further dynamics outside the edge channel.

Expanding Edges of Quantum Hall Systems in a Cosmology Language -- Hawking Radiation from de Sitter Horizon in Edge Modes

“…The dynamics in the bulk yield a large energy gap in its dispersion relations. In the bulk, there exist various gapped excitations such as magnetorotons [7][8][9][10] and anyonic quasiparticles [11][12][13]. The dispersion relation of the edge currents are firmly protected owing to the topological structure of the systems, and the edge excitations are always in gapless modes.…”

“…It is possible to express the same edge degrees of freedom by both a fermionic field and bosonic field via the statistics transmutation in one-dimensional space. It is known that the bosonic field corresponds to the charge density of the edge current, and can be directly observed by measuring the voltage deviation in the edge experiments [10,[20][21][22][23][24][25]. The edge effective theories are given by free field theories with a chiral condition.…”

“…Until now, all experiments of QH systems have been performed in a static situation, except for local edge excitations [10,[20][21][22][23][24]. The electrons are confined in the bulk region by the static electric field created by surface potential of host semiconductors of the 2D electrons.…”