Generation of entanglement and suppression of decoherence in ENDOR-based quantum computing

IICQI 2007
Talk type: 

The ultimate goal for the research on quantum computing is construction of a computational machine that deals entirely with quantum properties, such as entanglement, and remains stable and works reliably in the presence of decoherence. In an approach to this task, we use a resonance spectroscopy that involves simultaneously electron spins in addition to nuclear spins, that is called ENDOR. For this system, entanglement was realized between an electron and a nuclear spin [Mehring et al., Phys. Rev. Lett. 90, 153001 (2003), Rahimi et al., Intl. J. Quant. Inf. 3, 197 (2005)]. For making a full computational processor with ENDOR, it should be stabilized against influence of noise. Hence, we study methods with which decoherence in ENDOR would be suppressed. We show the numerical results indicating that the oscillation of the minimum negativity (over all bipartite splittings) due to the spin boson coupling and the decay of the minimum negativity under simple noise written in the Kraus operator sum form are both suppressed by sharp bang-bang pulses on individual spins. The achieved results are to be used for determination of optimum experimental conditions since they are in an operationally possible range. In our presentation, we are going to introduce recent results from our study, as well as giving a short overview on the achieved experimental evidences.