We proposed an efficient scheme for implementing the large-scale one-way Quantum computing (QC) with a novel hybrid solid-state quantum system. This system consists of N Nitrogen-vacancy (N-V) centers coupled to N separate Transmission line resonators (TLRs), which are interconnected by a Current-biased Josephson junction (CBJJ) superconducting phase qubit. We showed the way of preparation of N-qubit linear cluster state with N N-V centers, then we demonstrated the way of extending cluster state by connecting two pieces of linear cluster states into two-dimensional cluster state, last, with our designed new structures, we demonstrated the QC basic operations. It means that our scheme may open up promising possibilities for implementing the practical and scalable one-way quantum computers with the hybrid solid-state quantum system. We discussed the experimental feasibility of our system.
A design is proposed for scalable solid-state quantum computing, which is based on collectively enhanced magnetic coupling between nitrogen-vacancy center ensembles and superconducting transmission line resonators interconnected by current-biased Josephson junction superconducting phase qubit. In this hybrid system, we realize distant multi-qubit controlled phase gate operations and generate distant multi-qubit entangled W-like states, being indispensable resource to quantum computation. Our proposed architecture consists of solid-state spin ensembles and circuit QED, and could achieve quantum computing in a solid-state environment with high-fidelity and scalable way. The experimental feasibility is discussed, and the implementation efficiency is demonstrated numerically.
We study a hybrid quantum computing system using a nitrogen-vacancy center ensemble (NVE) as quantum memory, a current-biased Josephson junction (CBJJ) superconducting qubit fabricated in a transmission line resonator (TLR) as the quantum computing processor, and the microwave photons in TLR as the quantum data bus. The storage process is seriously treated by considering all kinds of decoherence mechanisms. Such a hybrid quantum device can also be used to create multiqubit
W states of NVEs through a common CBJJ. The experimental feasibility is achieved using currently available technology.
We demonstrate a scheme for realizing quantum-information storage (retrieval) into (from) a quantum memory using a hybrid quantum system, which consists of
N nitrogen-vacancy (N-
V) centers (as memory),
N transmission line resonators (TLRs) (as data bus), and
N current-biased Josephson-junction (CBJJ) superconducting phase qubits (as heads of read and write). By virtually exciting the vibrational modes of the TLRs, this can produce an effective coupling between the N-
V centers and the CBJJs in the system. Because the operation time ($\ensuremath{\sim}{10}^{\ensuremath{-}8}$ s) is much shorter than the decoherence time of the CBJJ ($\ensuremath{\sim}{10}^{\ensuremath{-}5}$ s), the quantum information can be transferred between the N-
V centers and the CBJJs easily. Owing to the strong-coupling condition $[\ensuremath{\lambda}/2\ensuremath{\pi}\ensuremath{\gg}({\ensuremath{\gamma}}_{eg},\ensuremath{\Gamma},{\ensuremath{\gamma}}_{\ensuremath{\phi}})]$ and the long coherence time ($\ensuremath{\sim}{10}^{\ensuremath{-}3}$ s) of the N-
V centers, the quantum information can be stored in the memory steadily, and it can be retrieved with a high fidelity (
>96). This scheme provides a scalable way of exchanging quantum information between different quantum interfaces, and has the experimental feasibility with currently available experimental technology.
We propose a novel scheme for generating N-qubit GHZ entangled state with a hybrid quantum system, which consists of N nitrogen-vacancy centers, N transmission line resonators, a current-biased Josephson junction superconducting qubit, and three kinds of interaction Hamiltonians. The proposal requires no adjustment of the qubit level spacings during the entire operation. Moreover, it is shown that the operation time is independent of the number of qubits. The present proposal is quite useful, and is a promising step to realize the large-sized quantum networks for quantum information processing and quantum computation.
With the local resonant interaction between a nitrogen-vacancy-center ensemble (NVE) and a superconducting coplanar resonator, and the single-qubit operation, we propose two protocols for the state transfer between two remote NVEs and for a fast controlled-phase (cphase) gate on these NVEs, respectively. This hybrid quantum system is composed of two distant NVEs coupled to separated high-
Q transmission line resonators (TLRs), which are interconnected by a current-biased Josephson-junction superconducting phase qubit. The fidelity of our state-transfer protocol is about
99.63 within the operation time of
70.60 ns. The fidelity of our cphase gate is about
98.15 within the operation time of
93.87 ns. Furthermore, using the cphase gate, we construct a two-dimensional cluster state on NVEs in a $n\ifmmode\times\else\texttimes\fi{}n$ square grid based on the hybrid quantum system for the one-way quantum computation. Our protocol may be more robust, compared with the one based on the superconducting resonators, due to the long coherence time of NVEs at room temperature.
We propose a potentially practical scheme for creating entanglement between two distant nitrogen-vacancy-center (N-
V) spin ensembles using a current-biased Josephson junction superconducting qubit and transmission line resonators. The idea provides a scalable way to an N-
V ensemble-based quantum network, which is close to the reach with currently available technology.