Influence of qubit displacements on quantum logic operations in a silicon-based quantum computer with constant interaction

Journal Article · Sun Oct 15 04:00:00 EDT 2006 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.74.042337· OSTI ID:20857855

Kamenev, D I; Berman, G P ^[1]; Tsifrinovich, V I ^[2]

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1. Theoretical Division, T-13, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
2. Department of Physics, Polytechnic University, Brooklyn, New York 11201 (United States)

The errors caused by qubit displacements from their prescribed locations in an ensemble of spin chains are estimated analytically and calculated numerically for a quantum computer based on phosphorus donors in silicon. We show that it is possible to polarize (initialize) the nuclear spins even with displaced qubits by using controlled-NOT gates between the electron and nuclear spins of the same phosphorus atom. However, a controlled-NOT gate between the displaced electron spins is implemented with large error because of the exponential dependence of exchange interaction constant on the distance between the qubits. If quantum computation is implemented on an ensemble of many spin chains, the errors can be small if the number of chains with displaced qubits is small.

• OSTI ID: 20857855
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 4 Vol. 74; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
74 ATOMIC AND MOLECULAR PHYSICS
ATOMS
DISTANCE
ELECTRONS
ERRORS
EXCHANGE INTERACTIONS
GATING CIRCUITS
PHOSPHORUS
QUANTUM COMPUTERS
QUANTUM MECHANICS
QUBITS
SILICON
SPIN