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Topological quantum computation based on chiral Majorana fermions.

ABSTRACT: The chiral Majorana fermion is a massless self-conjugate fermion which can arise as the edge state of certain 2D topological matters. It has been theoretically predicted and experimentally observed in a hybrid device of a quantum anomalous Hall insulator and a conventional superconductor. Its closely related cousin, the Majorana zero mode in the bulk of the corresponding topological matter, is known to be applicable in topological quantum computations. Here we show that the propagation of chiral Majorana fermions leads to the same unitary transformation as that in the braiding of Majorana zero modes and propose a platform to perform quantum computation with chiral Majorana fermions. A Corbino ring junction of the hybrid device can use quantum coherent chiral Majorana fermions to implement the Hadamard gate and the phase gate, and the junction conductance yields a natural readout for the qubit state.

SUBMITTER: Lian B

PROVIDER: S-EPMC6205432 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Topological quantum computation based on chiral Majorana fermions.

Lian Biao B Sun Xiao-Qi XQ Vaezi Abolhassan A Qi Xiao-Liang XL Zhang Shou-Cheng SC

Proceedings of the National Academy of Sciences of the United States of America 20181008 43

The chiral Majorana fermion is a massless self-conjugate fermion which can arise as the edge state of certain 2D topological matters. It has been theoretically predicted and experimentally observed in a hybrid device of a quantum anomalous Hall insulator and a conventional superconductor. Its closely related cousin, the Majorana zero mode in the bulk of the corresponding topological matter, is known to be applicable in topological quantum computations. Here we show that the propagation of chiral ...[more]

PMID: 30297431

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