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

Abstract

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.

References in corpus (9)

• Quantum state transfer and entanglement distribution among distant nodes in a quantum network
• Electron Spin-Relaxation Times of Phosphorus Donors in Silicon
• Repeat-Until-Success Quantum Computing
• Robust creation of entanglement between ions in spatially separate cavities
• Robust quantum gates on neutral atoms with cavity-assisted photon-scattering
• Towards the fabrication of phosphorus qubits for a silicon quantum computer
• Unconditional preparation of entanglement between atoms in cascaded optical cavities
• Engineering an interaction and entanglement between distant atoms
• Perturbation Theory for Quantum Computation with Large Number of Qubits