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1.
A one‐step scheme is presented to construct the controlled‐phase gate deterministically on remote transmon qutrits coupled to different resonators connected by a superconducting transmission line for an universal distributed quantum computing. Different from previous work on remote superconducting qubits, the present gate is implemented with coherent evolutions of the entire system in the all‐resonance regime assisted by the dark photons to robust against the transmission line loss, which allows the possibility of the complex designation of a long‐length transmission line to link lots of circuit QEDs. The length of the transmission line can reach the scale of several meters, which makes this scheme suitable for large‐scale distributed quantum computing. This gate is a fast quantum entangling operation with a high fidelity of about 99%. Compared with previous work in other quantum systems for a distributed quantum computing, under the all‐resonance regime, the present proposal does not require classical pulses and ancillary qubits, which relaxes the difficulty of its implementation largely. 相似文献
2.
A controlled teleportation scheme is presented. In this
scheme, quantum information of a single-qubit state or an entangled
two-qubits state is transmitted from a sender (Alice) to a receiver
(Charlie) via a four-particle cluster state under the control of the
supervisor (Bob). The feature of this scheme is that the teleportation
between the sender and the receiver depends on the control of the
supervisor. 相似文献
3.
Simon CM Belhadj T Chatel B Amand T Renucci P Lemaitre A Krebs O Dalgarno PA Warburton RJ Marie X Urbaszek B 《Physical review letters》2011,106(16):166801
The energy states in semiconductor quantum dots are discrete as in atoms, and quantum states can be coherently controlled with resonant laser pulses. Long coherence times allow the observation of Rabi flopping of a single dipole transition in a solid state device, for which occupancy of the upper state depends sensitively on the dipole moment and the excitation laser power. We report on the robust population inversion in a single quantum dot using an optical technique that exploits rapid adiabatic passage from the ground to an excited state through excitation with laser pulses whose frequency is swept through the resonance. This observation in photoluminescence experiments is made possible by introducing a novel optical detection scheme for the resonant electron hole pair (exciton) generation. 相似文献
4.
YANG Wen-Xing CHEN Ai-Xi 《理论物理通讯》2008,49(4):913-918
In the system with superconducting quantum interference devices (SQUID) in cavity, a scheme for constructing two-qubit quantum phase gate via a conventional geometric phase-shift is proposed by using a quantized cavity field and classical microwave pulses. In this scheme, the gate operation is realized in the subspace spanned by the two lower flux states of the SQUID system mud the population operator of the excited state has no effect on it. Thus the effect of decoherence caused from the levels of the SQUID system is possible to minimize. Under cavity decay, our strictly numerical simulation shows that it is also possible to realize the unconventional geometric phase gate. The experimental feasibility is discussed in detail. 相似文献
5.
A scheme for probabilistic teleportation of an unknown three-atom entangled state via a five-atom non-maximally entangled cluster state as quantum channel is proposed. In this scheme, the sender performs two Bell state and a single-atom measurements on the atoms, the receiver can reconstruct the original state with a certain probability by introducing an auxiliary atom and operating appropriate unitary transformations and controlled-not (C-not) operations according to the sender Alice's measurement results. As a result, the probability of successful teleportation is determined by the smallest two of the coefficients'absolute values of the cluster state. The considerable advantage of our scheme is that we employ a non-maximally entangled cluster state as quantum channel in the scheme, which can greatly reduce the amount of entanglement resources and need less classical bits. If we employ a maximally entangled cluster state as quantum channel, the probabilistic teleportation scheme becomes usual teleportation, the successful probability being 100%. 相似文献
6.
One-way quantum computing allows any quantum algorithm to be implemented easily using just measurements. The difficult part is creating the universal resource, a cluster state, on which the measurements are made. We propose a scalable method that uses a single, multimode optical parametric oscillator (OPO). The method is very efficient and generates a continuous-variable cluster state, universal for quantum computation, with quantum information encoded in the quadratures of the optical frequency comb of the OPO. 相似文献
7.
Yu Wang Yi-Hao Kang Chang-Sheng Hu Bi-Hua Huang Jie Song Yan Xia 《Frontiers of Physics》2022,17(3):32501
We propose a quantum control scheme with the help of Lyapunov control function in the optomechanics system. The principle of the idea is to design suitable control fields to steer the Lyapunov control function to zero as t → ∞ while the quantum system is driven to the target state. Such an evolution makes no limit on the initial state and one needs not manipulate the laser pulses during the evolution. To prove the effectiveness of the scheme, we show two useful applications in the optomechanics system: one is the cooling of nanomechanical resonator and the other is the quantum fluctuation transfer between membranes. Numerical simulation demonstrates that the perfect and fast cooling of nanomechanical resonator and quantum fluctuation transfer between membranes can be rapidly achieved. Besides, some optimizations are made on the traditional Lyapunov control waveform and the optimized bang–bang control fields makes Lyapunov function V decrease faster. The optimized quantum control scheme can achieve the same goal with greater efficiency. Hence, we hope that this work may open a new avenue of the experimental realization of cooling mechanical oscillator, quantum fluctuations transfer between membranes and other quantum optomechanics tasks and become an alternative candidate for quantum manipulation of macroscopic mechanical devices in the near future. 相似文献
8.
Jia-Yin Peng Hong-Xuan Lei Zhi-Wen Mo 《International Journal of Theoretical Physics》2014,53(5):1637-1647
The previous protocols of remote quantum information concentration were focused on the reverse process of quantum telecloning of single-qubit states. We here investigate the reverse process of optimal universal 1→2 telecloning of arbitrary two-qubit states. The aim of this telecloning is to distribute respectively the quantum information to two groups of spatially separated receivers from a group of two senders situated at two different locations. Our scheme shows that the distributed quantum information can be remotely concentrated back to a group of two different receivers with 1 of probability by utilizing maximally four-particle cluster state and four-particle GHZ state as quantum channel. 相似文献
9.
We investigate experiments of continuous-variable quantum information processing based on the teleportation scheme. Quantum
teleportation, which is realized by a two-mode squeezed vacuum state and measurement-and-feedforward, is considered as an
elementary quantum circuit as well as quantum communication. By modifying ancilla states or measurement-and-feedforwards,
we can realize various quantum circuits which suffice for universal quantum computation. In order to realize the teleportation-based
computation we improve the level of squeezing, and fidelity of teleportation. With a high-fidelity teleporter we demonstrate
some advanced teleportation experiments, i.e., teleportation of a squeezed state and sequential teleportation of a coherent
state. Moreover, as an example of the teleportation-based computation, we build a QND interaction gate which is a continuous-variable
analog of a CNOT gate. A QND interaction gate is constructed only with ancillary squeezed vacuum states and measurement-and-feedforwards.
We also create continuous-variable four mode cluster type entanglement for further application, namely, one-way quantum computation. 相似文献
10.
We present a scalable scheme to design optimized soft pulses and pulse sequences for coherent control of interacting quantum many-body systems. The scheme is based on the cluster expansion and the time-dependent perturbation theory implemented numerically. This approach offers a dramatic advantage in numerical efficiency, and it is also more convenient than the commonly used Magnus expansion, especially when dealing with higher-order terms. We illustrate the scheme by designing 2nd-order self-refocusing pi pulses and a 6th-order 8-pulse refocusing sequence for a chain of qubits with nearest-neighbor couplings. We also discuss the performance of soft-pulse refocusing sequences in suppressing decoherence due to low-frequency environment. 相似文献
11.
A scheme for probabilistic teleportation of an unknown three-qubit entangled state via a five-qubit non-maximally entangled cluster state as quantum channel is proposed. In this scheme, the sender performs two Bell state and a single-qubit measurements on the qubits, the receiver can reconstruct the original state with a certain probability by making appropriate unitary transformations and controlled-not (C-not) operations. As a result, the probability of successful teleportation is determined by the smallest two of the coefficients’ absolute values of the cluster state. The considerable advantage of our scheme is that we employ a non-maximally entangled cluster state as quantum channel in the scheme, which can greatly reduce the amount of entanglement resources and need less classical bits. 相似文献
12.
13.
In this paper, we present a scheme for quantum dialogue by using a four-qubit cluster state as quantum channel.The scheme has two cases: Case 1, Sender Alice and receiver Bob share information using an orderly sequence of entangled state as quantum channel which was prepared by Alice. This case is achieved as follows: The two sides agreed to encode quantum state information, then Alice perform a bell state measurement for quantum information which has been encoded. This will convey the information to Bob, then Bob measuring his own qubits, through the analysis of the measurement results of Alice and Bob, Bob can obtain quantum information. For case 2, four-qubit cluster state and quantum state information is transmitted to form a total quantum system. In the Case 2 scenario, Alice and Bob perform bell state measurements for part of the qubits, and tell the measurement result to each other through the classical channel. Finally, according to the measurement result, Alice and Bob operate an appropriate unitary transformation, as a result, Alice’s qubit will be renewed upon Bob’s measurements, and also, Bob’s qubit will be renewed upon Alice’s measurements. Thus, a bidirectional quantum dialogue is achieved. After analysis, this scheme has high security by taking certain eavesdropping attacks into account. There is therefore a certain reference value to the realization of quantum dialogue. 相似文献
14.
针对"即插即用"双向量子密钥分发系统传输效率低的实际问题, 详细分析了系统低效的原因和当前的解决方案, 提出了一种单光源多波长双向量子密钥分发方案. 该方案采用波分复用器件作为滤波器来产生量子密钥分发所需的多波长信号. 与其他多波长方案相比, 该方案的优点是在实现高速多波长量子密钥分发时, 不再受外界控制源调制速率和精度等性能的影响, 不再带来多激光器引入的边信道攻击的缺陷, 且整体系统易于集成. 该方案为"即插即用"量子密钥分发系统的高效研究提供了一个新的参考方案. 相似文献
15.
An intuitive scheme for controlling the quantum state composition of one-coordinate molecular wave packets is developed. The accumulated phase difference between the various components of the molecular wave packet is determined, and then a sequence of phase-locked optical pulses is employed to selectively enhance or depopulate specific vibrational states, or sets of vibrational states. The quantum state composition of the resulting wave packet, and the efficiency of the control scheme, is determined by calculating the multi-pulse response of the time-dependent vibrational state populations. 相似文献
16.
This paper proposes a simple scheme to generate a
four-atom entangled cluster state in cavity quantum electrodynamics.
With the assistantce of a strong classical field the cavity is only
virtually excited and no quantum information will be transferred
from the atoms to the cavity during the preparation for a four-atom
entangled cluster state, and thus the scheme is insensitive to the
cavity field states and cavity decay. Assuming that deviation of
laser intensity is 0.01 and that of simultaneity for the interaction
is 0.01, it shows that the fidelity of the resulting four-atom
entangled cluster state is about 0.9886. The scheme can also be
used to generate a four-ion entangled cluster state in a hot
trapped-ion system. Assuming that deviation of laser intensity is
0.01, it shows that the fidelity of the resulting four-ion entangled
cluster state is about 0.9990. Experimental feasibility for
achieving this scheme is also discussed. 相似文献
17.
提出一种把量子隐形传态、最佳普适量子比特翻转和最佳普适量子克隆三者结合起来的量子比特普适远程翻转和克隆方案.当发送者和处于不同地点的三个接收者共享一个特定的四粒子纠缠态作为量子信道时,通过发送者的Bell基测量、经典通信和各个接收者的局域幺正变换,一个接收者能够以2/3的最佳保真度得到一份原未知量子比特的正交补态,另外两个接收者能够分别以5/6的最佳保真度得到原未知量子比特的一份拷贝.此方案用较少的量子纠缠资源同时完成了未知量子比特的普适远程翻转和克隆,且其保真度分别达到了最佳.实现此方案的关键在于构造出发送者和接收者共享的特定四粒子纠缠态作为量子信道,分析了此特殊四粒子态内在的纠缠结构. 相似文献
18.
Ming-Feng Chen Li-Tuo Shen Rong-Xin Chen Zhen-Biao Yang 《International Journal of Theoretical Physics》2016,55(3):1361-1369
We propose a scheme for quantum state transfer within the high-dimensional state subspaces between any two nodes in a quantum network. The states are encoded in the collective ground states of multiple atoms. The transfer processes are controlled by only applying external laser pulses. The prominent feature of the scheme is that the state transfer of any dimension can be achieved through virtually coupling all the excitations of the total system. 相似文献
19.
Invariant‐Based Pulse Design for Three‐Level Systems Without the Rotating‐Wave Approximation 下载免费PDF全文
In this paper, a scheme is put forward to design pulses which drive a three‐level system based on the reverse engineering with Lewis‐Riesenfeld invariant theory. The scheme can be applied to a three‐level system even when the rotating‐wave approximation (RWA) can not be used. The amplitudes of pulses and the maximal values of detunings in the system could be easily controlled by adjusting control parameters. We analyze the dynamics of the system by an invariant operator, so additional couplings are unnecessary. Moreover, the approaches to avoid singularity of pulses are studied and several useful results are obtained. We hope the scheme could contribute to fast quantum information processing without RWA. 相似文献
20.
Two different schemes are presented for quantum teleportation of an arbitrary two-qudit state using a non-maximally four-qudit
cluster state as the quantum channel. The first scheme is based on the Bell-basis measurements and the receiver may probabilistically
reconstruct the original state by performing proper transformation on her particles and an auxiliary two-level particle; the
second scheme is based on the generalized Bell-basis measurements and the probability of successfully teleporting the unknown
state depends on those measurements which are adjusted by Alice. A comparison of the two schemes shows that the latter has
a smaller probability than that of the former and contrary to the former, the channel information and auxiliary qubit are
not necessary for the receiver in the latter.
Supported by the Natural Science Research Project of Shanxi Province (Grant No. 2004A15) 相似文献