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Threshold Error Penalty for Fault Tolerant Computation with Nearest Neighbour Communication

T. Szkopek·P. O. Boykin·H. Fan·V. Roychowdhury·E. Yablonovitch·G. Simms·M. Gyure·B. Fong
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Abstract

The error threshold for fault tolerant quantum computation with concatenated encoding of qubits is penalized by internal communication overhead. Many quantum computation proposals rely on nearest-neighbour communication, which requires excess gate operations. For a qubit stripe with a width of L+1 physical qubits implementing L levels of concatenation, we find that the error threshold of 2.1x10^-5 without any communication burden is reduced to 1.2x10^-7 when gate errors are the dominant source of error. This ~175X penalty in error threshold translates to an ~13X penalty in the amplitude and timing of gate operation control pulses.

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T. Szkopek, P. O. Boykin, H. Fan, V. Roychowdhury, E. Yablonovitch, G. Simms, M. Gyure, B. Fong. 2005-09-08. Threshold Error Penalty for Fault Tolerant Computation with Nearest Neighbour Communication. https://doi.org/10.1109/tnano.2005.861402

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