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arXiv · 1802.05205

Self-Organised Fractional Quantisation in a Hole Quantum Wire

Y. Gul·S. N. Holmes·M. Myronov·S. Kumar·M. Pepper
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Abstract

We have investigated hole transport in one-dimensional quantum wires in strained germanium two-dimensional layers. The ballistic conductance characteristics show the regular quantised plateaux in units of n2e2/h, where n is an integer. Additionally, new quantised levels are formed which correspond to values of n = 1/4 reducing to 1/8 in the presence of a strong parallel magnetic field which lifts the spin degeneracy but does not quantise the wavefunction. A further plateau is observed corresponding to n = 1/32 which does not change in the presence of a parallel magnetic field. These values indicate that the system is behaving as if charge was fractionalised with values e/2 and e/4, possible mechanisms are discussed.

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Y. Gul, S. N. Holmes, M. Myronov, S. Kumar, M. Pepper. 2018-02-14. Self-Organised Fractional Quantisation in a Hole Quantum Wire. https://doi.org/10.1088/1361-648x/aaabab

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