arXiv subjects

Puhao Cao

Publications and source records attributed to Puhao Cao.

2 recordsLinked to original sources

arXiv2018

Scalable nuclear-spin entanglement mediated by a mechanical oscillator

We propose a solid-state hybrid platform based on an array of implanted nitrogen-vacancy (NV) centers in diamond magnetically coupled to a mechanical oscillator. The mechanical oscillator and the NV electronic spins both act as a quantum bus and allow us to induce an effective long-range interaction between distant nuclear spins, relaxing the requirements on their spatial distance. The coherent nuclear spin-spin interaction, having the form of an Ising model, can be maintained in the presence of mechanical damping and spin dephasing via a pulsed dynamical decoupling of the nuclear spins in addition to the microwave driving field of the electronic spins. The present hybrid platform provides a scalable way to prepare multipartite entanglement among nuclear spins with long coherence times and can be applied to generate graph states that may be used for universal quantum computing.

quant-ph↗

arXiv2018

Entangling distant solid-state spins via thermal phonons

The implementation of quantum entangling gates between qubits is essential to achieve scalable quantum computation. Here, we propose a robust scheme to realize an entangling gate for distant solid-state spins via a mechanical oscillator in its thermal equilibrium state. By appropriate Hamiltonian engineering and usage of a protected subspace, we show that the proposed scheme is able to significantly reduce the thermal effect of the mechanical oscillator on the spins. In particular, we demonstrate that a high entangling gate fidelity can be achieved even for a relatively high thermal occupation. Our scheme can thus relax the requirement for ground-state cooling of the mechanical oscillator, and may find applications in scalable quantum information processing in hybrid solid-state architectures.

quant-ph↗