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Scalable fault-tolerant quantum computation in DFS blocks

Zheng-Wei Zhou·Bo Yu·Xingxiang Zhou·Marc J. Feldman·Guang-Can Guo
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Abstract

We investigate how to concatenate different decoherence-free subspaces (DFSs) to realize scalable universal fault-tolerant quantum computation. Based on tunable $XXZ$ interactions, we present an architecture for scalable quantum computers which can fault-tolerantly perform universal quantum computation by manipulating only single type of parameter. By using the concept of interaction-free subspaces we eliminate the need to tune the couplings between logical qubits, which further reduces the technical difficulties for implementing quantum computation.

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Zheng-Wei Zhou, Bo Yu, Xingxiang Zhou, Marc J. Feldman, Guang-Can Guo. 2004-07-29. Scalable fault-tolerant quantum computation in DFS blocks. https://doi.org/10.1103/physrevlett.93.010501

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