arXiv subjects

D. Blazina

Publications and source records attributed to D. Blazina.

4 recordsLinked to original sources

arXiv2004

Practical Implementations of Twirl Operations

Twirl operations, which convert impure singlet states into Werner states, play an important role in many schemes for entanglement purification. In this paper we describe strategies for implementing twirl operations, with an emphasis on methods suitable for ensemble quantum information processors such as nuclear magnetic resonance (NMR) quantum computers. We implement our twirl operation on a general two-spin mixed state using liquid state NMR techniques, demonstrating that we can obtain the singlet Werner state with high fidelity.

quant-ph↗

arXiv2004

Implementing Grover's Quantum Search on a Para-Hydrogen based Pure State NMR Quantum Computer

We demonstrate the implementation of Grover's quantum search algorithm on a liquid state nuclear magnetic resonance (NMR) quantum computer using essentially pure states. This was achieved using a two qubit device where the initial state is an essentially pure ($ε=1.06\pm0.04$) singlet nuclear spin state of a pair of 1H nuclei arising from a chemical reaction involving para-hydrogen. We have implemented Grover's search to find one of four inputs which satisfies a function.

quant-ph↗

arXiv2004

Implementation of NMR quantum computation with para-hydrogen derived high purity quantum states

We demonstrate the first implementation of a quantum algorithm on a liquid state nuclear magnetic resonance (NMR) quantum computer using almost pure states. This was achieved using a two qubit device where the initial state is an almost pure singlet nuclear spin state of a pair of 1H nuclei arising from a chemical reaction involving para-hydrogen. We have implemented Deutsch's algorithm for distinguishing between constant and balanced functions with a single query.

quant-ph↗

arXiv2004

Preparing high purity initial states for nuclear magnetic resonance quantum computing

Here we demonstrate how para-hydrogen can be used to prepare a two-spin system in an almost pure state which is suitable for implementing nuclear magnetic resonance (NMR) quantum computation. A 12ns laser pulse is used to initiate a chemical reaction involving pure para-hydrogn (the nuclear spin singlet of H2). The product, formed on the microsecond timescale, 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) effective spin temperature of 6.4mK or an impractical magnetic field of 0.45MT at room temperature. The resulting spin state has an entanglement of formation of 0.822 and cannot be described by local hidden variable models.

quant-ph↗