Research PapersNo Access

MINIMAL EXECUTION TIME OF SHOR'S ALGORITHM AT LOW TEMPERATURES

M. A. AVILA

Centro Universitario UAEM Valle de Chalco, UAEMex, Valle de Chalco, CP 56615, Edo. de México, México

https://doi.org/10.1142/S0219749909004475Cited by:0 (Source: Crossref)

Abstract

The minimal time, T^Shor, in which a one-way quantum computer can execute Shor's algorithm is derived. In the absence of an external magnetic field, this quantity diverges at very small temperatures. This result coincides with that of Anders et al. obtained simultaneously to ours but using thermodynamical arguments. Such divergence contradicts the common belief that it is possible to do quantum computation at low temperatures. It is shown that in the presence of a weak external magnetic field, T^Shor becomes a quantized quantity which vanishes at zero temperature. Decoherence is not a problem because T^Shor/τ_dec < 10^-9, where τ_dec is decoherence time.

Keywords:

PACS: 87.17.Aa, 89.20.Ff

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