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arXiv · 2102.00620

Quantum operation of fermionic systems and process tomography using Majorana fermion gates

Gang Zhang·Mingxia Huo·Ying Li
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Abstract

Quantum tomography is an important tool for the characterisation of quantum operations. In this paper, we present a framework of quantum tomography in fermionic systems. Compared with qubit systems, fermions obey the superselection rule, which sets constraints on states, processes and measurements in a fermionic system. As a result, we can only partly reconstruct an operation that acts on a subset of fermion modes, and the full reconstruction always requires at least one ancillary fermion mode in addition to the subset. We also report a protocol for the full reconstruction based on gates in Majorana fermion quantum computer, including a set of circuits for realising the informationally-complete state preparation and measurement.

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Gang Zhang, Mingxia Huo, Ying Li. 2021-02-01. Quantum operation of fermionic systems and process tomography using Majorana fermion gates. https://arxiv.org/abs/2102.00620

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