Observation of 3/2 even-denominator fractional quantum Hall plateau

2019/09/25

 Xi Lin and X. C. Xie from Peking University, associated with Beijing Academy of Quantum Information Sciences, reported their work on a 3/2 even-denominator fractional quantum Hall plateau on [Nature Communications] in 09/2019. They have observed a 3/2 FQH plateau in a single-layer 2DEG with lateral confinement at a bulk filling factor of 5/3, which suggests a tunneling conductance of 1/6 e^2/h. The 3/2 FQH plateau is quantized within 0.02%. X. C. Xie proposed that through tunneling-induced topological phase transition in a confined region, the further 1/2 quantization of the quasi-particles with e/3 fractional charge causes this 1/6 e^2/h backscattering and e/6 fractional charge. Such surprising results suggest that the eigenstate of the many-body interactions with boundary condition can be completely different from that in the open space.
    Figure: Magnetic field dependence of the diagonal resistance with different gate voltages. The diagonal resistance develops an unexpected 3/2 plateau from the 5/3 FQH plateau after the confinement condition is changed. [Nature Communications 10, 4351 (2019)]