Fractionally charged quasiparticles

摘要

Fractionally charged quasiparticles were proposed by Laughlin to explain the fractional quantum Hall effect. Flowing in one dimensional-like strips along the edges of the sample, the quasiparticles are expected to condense to a chiral Luttinger liquid. Adding a backscattering impurity in the path of the quasiparticles led to strongly correlated scattering events producing, at sufficiently low temperatures, highly non-linear I-V characteristics and non-classical shot noise. Moreover, a strong backscatterer induced bunching of the quasiparticles resulting in enhanced noise corresponding to an effective charge of one electron. However, when the impinging quasiparticle beam was very dilute or the temperature increased, scattering events were independent. Surprisingly, in that regime, bunching ceased and fractionally charged quasiparticles were found to traverse almost opaque barriers.