Anwar, M.S., Blazina, D., Carteret, H.A., Duckett, S.B., Halstead, T.K., Jones, J.A., Kozak, C.M. and Taylor, R.J.K. (2004) Preparing high purity initial states for nuclear magnetic resonance quantum computing. Physical Review Letters, 93 (4). 040501-4 pages. ISSN 0031-9007
Here we demonstrate how parahydrogen can be used to prepare a two-spin system in an almost pure state which is suitable for implementing nuclear magnetic resonance quantum computation. A 12 ns laser pulse is used to initiate a chemical reaction involving pure parahydrogen (the nuclear spin singlet of H2). The product, formed on the μs time scale, contains a hydrogen-derived two-spin system with an effective spin-state purity of 0.916. To achieve a comparable result by direct cooling would require an unmanageable (in the liquid state) temperature of 6.4 mK or an impractical magnetic field of 0.45 MT at room temperature. The resulting spin state has an entanglement of formation of 0.822 and cannot be described by local hidden variable models.
|Institution:||The University of York|
|Academic Units:||The University of York > Physics (York)|
|Depositing User:||York RAE Import|
|Date Deposited:||25 Feb 2009 15:13|
|Last Modified:||25 Feb 2009 15:13|
|Publisher:||American Physical Society|