Amazing stuff!
"... In a series of experiments at extremely cold conditions, close to -459°F (-273°C), and under a magnetic field nearly 100,000 times stronger than Earth’s, Mani, Wijewardena and colleagues went to work. They applied a supplementary current to high mobility semiconductor devices made from a sandwich structure of gallium arsenide (GaAs) and aluminum gallium arsenide (AlGaAs) materials, which helps to realize electrons in a flatland. They observed all the FQHE states splitting unexpectedly, followed by crossings of split branches, which allowed them to explore the new non-equilibrium states of these quantum systems and reveal entirely new states of matter. The study highlights the crucial role of high-quality crystals ..."
From the abstract:
"Studies of fractional quantum Hall effects (FQHE) across various two-dimensional electronic systems (2DES) have helped to establish the equilibrium FQHE many-body ground states with fractionally charged excitations and composite particles in condensed matter. Then, the question arises whether an FQHE system driven to non-equilibrium can approach a different stationary state from the known equilibrium FQHE states. To investigate this question, we examine FQHE over filling factors, ν, 2 ≥ ν ≥ 1 under non-equilibrium finite bias conditions realized with a supplementary dc-current bias, IDC, in high mobility GaAs/AlGaAs devices. Here, we show that all observable canonical equilibrium FQHE resistance minima at ∣IDC∣ = 0 undergo bimodal splitting vs. IDC, yielding branch-pairs and diamond shapes in color plots of the diagonal resistance, as canonical FQHE are replaced, with increasing IDC, by excited-state fractionally quantized Hall effects at branch intersections. A tunneling model serves to interpret the results."
Georgia State Discovery Provides Insight Into Behavior of Electrons (original news release)
Fig. 3: Splitting of equilibrium FQHE states under current bias.
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