共查询到20条相似文献,搜索用时 31 毫秒
1.
CHEN Chang-Yong 《理论物理通讯》2008,49(4):871-876
We propose a potentially practical scheme to implement an approximate three-qubit Toffoli gate by a single resonant interaction in dissipative cavity QED in which the cavity mode decay and atomic spontaneous emission are considered. The scheme does not require two-qubit controlled-NOT gates but uses a three-qubit phase gate and two Hadamard gates, where the approximate phase gate can be implemented by only a single dissipative resonant interaction of atoms with the cavity mode. Discussions are made for the advantages and the experimental feasibility of our scheme. 相似文献
2.
用腔场中的二能级势阱离子实现量子逻辑门 总被引:1,自引:0,他引:1
利用光腔中的势阱粒子同时与外激光场和腔场发生相互作用的特性,我们提出了一种量子逻辑门的实现方案。在该方案中,我们采用文献[10-12]中的模型。文献[11-12]中实现的逻辑门是以离子内态和运动态作为量子比特,腔态充当辅助比特在计算过程中保持在基态。而[10]要求离子内态保持为基态,利用离子运动态和腔态构成量子比特。与文献[10-12]不同的是,我们实现的量子逻辑门是以粒子内态和腔态作为比特,而势阱离子的运动态作为辅助比特始终保持在基态。而且,我们对该方案的实验要求进行了讨论。 相似文献
3.
In the system with two two-level ions confined in a linear trap,
this paper presents a simple scheme to realize the quantum phase
gate (QPG) and the swap gate beyond the Lamb--Dicke (LD) limit.
These two-qubit quantum logic gates only involve the internal states
of two trapped ions. The scheme does not use the vibrational mode as
the data bus and only requires a single resonant interaction of the
ions with the lasers. Neither the LD approximation nor the auxiliary
atomic level is needed in the proposed scheme. Thus the scheme is
simple and the interaction time is very short, which is important in
view of decoherence. The experimental feasibility for achieving this
scheme is also discussed. 相似文献
4.
Quantum controlled phase gate and cluster states
generation via two superconducting quantum interference devices in a
cavity 总被引:3,自引:0,他引:3
Z.-Y. Xue G. Zhang P. Dong Y.-M. Yi Z.-L. Cao 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,52(3):333-336
A scheme for implementing 2-qubit quantum controlled phase gate (QCPG) is proposed with two superconducting quantum interference
devices (SQUIDs) in a cavity. The gate operations are
realized within the two lower flux states of the SQUIDs by using a quantized cavity field and classical microwave pulses.
Our scheme is achieved without any type of measurement, does not use the cavity mode as the data bus and only requires a very
short resonant interaction of the SQUID-cavity system. As an application of the QCPG operation, we also propose a scheme for
generating the cluster
states of many SQUIDs. 相似文献
5.
Resonant scheme for realizing quantum phase gates for two separate atoms via coupled cavities 总被引:1,自引:0,他引:1
We propose a scheme for realizing conditional quantum phase gates for two atoms that are distributed in two coupled cavities. Due to the resonant interaction in temporal evolution of the entire system, the gate operation time is greatly reduced as compared with that of the nonresonant schemes. We study the influence of imperfections in the interaction and the effect of decoherence and find the gate to be robust. We discuss the issue related to the practical implementation and show that the gate is accessible within the current cavity QED technology. 相似文献
6.
Deng-Yu Zhang Shi-Qing Tang Li-Jun Xie Xiao-Gui Zhan Kai-Ming You Feng Gao 《International Journal of Theoretical Physics》2009,48(9):2685-2691
We propose a model to implement the two-qubit quantum logic gates, i.e., the quantum phase gate and the Controlled-NOT gate,
and generate the atomic qubits cluster states with a large detuned interaction between four-level atoms and a single-mode
cavity field. In the presented protocol, the quantum information is encoded on the stable ground states of the atoms, and
the effect of decoherence from atomic spontaneous emission is negligible. In addition, the interaction between atoms and the
cavity is large detuned, and the cavity is only virtually excited. Therefore, the scheme is insensitive to the cavity decay.
The experimental feasibility of our proposal is also discussed. 相似文献
7.
Xiao-Qiang Shao Hong-Fu Wang Li Chen Shou Zhang Yong-Fang Zhao Kyu-Hwang Yeon 《Optics Communications》2009,282(23):4643-4646
We show that a three-qubit phase gate on three modes of a cavity can be realized via resonant atom–cavity interaction. By introducing two strong classical fields and modulating the amplitudes, we obtain the effective form of nonlinear interaction between photons in the three-mode cavity. The availability is testified via numerical analysis. We also consider both the situations with and without effect of decoherence. 相似文献
8.
In this paper, the synthesis and implementation of three-qubit SWAP gate is discussed. The three-qubit SWAP gate can be decomposed into product of 2 two-qubit SWAP gates, and it can be realized by 6 CNOT gates. Research illustrated that although the result is very simple, the current methods of matrix decomposition for multi-qubit gate can not get that. Then the implementation of three-qubit SWAP gate in the three spin system with Ising interaction is investigated and the sequence of control pulse and drift process to implement the gate is given. It needs 23 control pulses and 12 drift processes. Since the interaction can not be switched on and off at will, the realization of three-qubit SWAP gate in specific quantum system also can not simply come down to 2 two-qubit SWAP gates. 相似文献
9.
We propose a method to prepare multipartite entangled states such as cluster states and graph states based on the cavity input-output process and single photon measurement. Two quantum gates, a controlled phase gate and a fusion gate between two atoms trapped in respective cavities, are proposed to prepare atomic cluster states and graph states with one and two dimensions. We also introduce a scheme that can generate an arbitrary multipartite photon duster state which uses two coherent states as a qubit basis. 相似文献
10.
Multiqubit CCZ gates form one of the building blocks of quantum algorithms and have been involved in achieving many theoretical and experimental triumphs. Designing a simple and efficient multiqubit gate for quantum algorithms is still by no means trivial as the number of qubits increases. Here, by virtue of the Rydberg blockade effect, we propose a scheme to rapidly implement a three-Rydberg-atom CCZ gate via a single Rydberg pulse, and successfully apply the gate to realize the three-qubit refined Deutsch–Jozsa algorithm and three-qubit Grover search. The logical states of the three-qubit gate are encoded to the same ground states to avoid an adverse effect of the atomic spontaneous emission. Furthermore, there is no requirement for individual addressing of atoms in our protocol. 相似文献
11.
12.
Optimal implementation of quantum gates is crucial for realization of quantum computation. We slightly modify the Khaneja-Glaser decomposition (KGD) for n-qubits and give a new Cartan subalgbra in the second step of the decomposition. Based on this modified KGD, we investigate the realization of three-qubit logic gate and obtain the result that a general three-qubit quantum logic gate can be implemented using at most 73 one-qubit gates rotations with respect to the y and z axes and 26 CNOT gates. 相似文献
13.
A protocol is proposed to implement a three-qubit phase gate for photonic qubits in a three-mode cavity. The idea can be extended to directly implement a N-qubit phase gate. We also show that the interaction time remains unchanged with the increasing number of qubits. In addition, the influence of cavity decay and atomic spontaneous emission on the gate fidelity and photon loss probability is also discussed by numerical calculation. 相似文献
14.
利用大失谐腔场中的两个原子实现量子相位门 总被引:1,自引:1,他引:0
本文讨论同时囚禁于单模、大失谐腔场中两个不同原子构成的系统,结论指出:只要仔细选择两不同原子的跃迁频率差、原子与腔场相互作用时间,可实现一个快速的量子相位门。这一方案不需要辅助的原子能级。 相似文献
15.
Two simple schemes for implementing Toffoli gate via atom--cavity field interaction in cavity quantum electrodynamics 下载免费PDF全文
This paper proposes two schemes for implementing three-qubit Toffoli
gate with an atom (as target qubit) sent through a two-mode cavity
(as control qubits). The first scheme is based on the large-detuning
atom--cavity field interaction and the second scheme is based on the
resonant atom-field interaction. Both the situations with and
without cavity decay and atomic spontaneous emission are considered.
The advantages and the experimental feasibility of these two schemes
are discussed. 相似文献
16.
Chui-Ping Yang 《Physics letters. A》2008,372(16):2782-2786
We present a new scheme for realizing a n-qubit controlled-phase gate with atoms in cavity QED. The present scheme operates essentially by exchanging a single photon between the control atoms and the cavity mode before and after a phase shift performed on the target atom. It is interesting to note that the gate can be implemented in a very simple way and by employing resonant interaction with one cavity only. 相似文献
17.
A scheme is proposed for generating three-dimensional maximally entangled states for two atoms. In the scheme the atoms are trapped in a two-mode cavity. The scheme only requires a single resonant interaction of the atoms with the cavity modes. Therefore, the scheme is very simple and required interaction time is very short, which is important in view of decoherence. 相似文献
18.
Resonant interaction scheme for GHZ state preparation and quantum phase gate with superconducting qubits in a cavity 下载免费PDF全文
A scheme is proposed to generate GHZ state and realize quantum phase gate for superconducting qubits placed in a microwave cavity. This scheme uses resonant interaction between the qubits and the cavity mode, so that the interaction time is short, which is important in view of decoherence. In particular, the phase gate can be realized simply with a single interaction between the qubits and the cavity mode. With cavity decay being considered, the fidelity and success probability are both very close to unity. 相似文献
19.
Zhi-Ming Zhan 《Physica A》2007,385(2):781-785
We propose a method for realizing the quantum controlled-NOT gate with a single resonant interaction in cavity QED. Our scheme only requires a single resonant interaction between two atoms and a cavity mode. Thus the scheme is very simple and the quantum dynamics operation can be realized at a high speed, which is important in view of decoherence. In addition, we also show that the gate can be realized in the ion trap system. 相似文献
20.
Zheng SB 《Physical review letters》2003,90(21):217901
We propose a scheme for realizing two-qubit quantum phase gates with trapped ions in thermal motion. In the scheme, the ions are simultaneously illuminated by a standing-wave laser tuned to the carrier, which virtually excites several vibrational modes. The scheme puts no limitations on the intensity of the laser field, allowing the production of a quantum logic gate for hot ions with an arbitrarily high speed as long as a laser field of sufficiently high intensity is available. 相似文献