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Related papers: A Note on the Speed of Perfect State Transfer

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We introduce an analytical $XX$ spin chain with asymmetrical transport properties. It has an even number $N+1$ of sites labeled by $n=0,\cdots N$. It does not exhibit perfect state transfer (PST) from end-to-end but rather from the first…

Quantum Physics · Physics 2020-01-08 Gabriel Coutinho , Luc Vinet , Hanmeng Zhan , Alexei Zhedanov

We study the protocol known as quantum state transfer for a strongly coupled antiferromagnetic spin chain or ring (acting as a spin bus), with weakly coupled external qubits. By treating the weak coupling as a perturbation, we find that…

Quantum Physics · Physics 2013-04-25 Sangchul Oh , Lian-Ao Wu , Yun-Pil Shim , Mark Friesen , Xuedong Hu

In a recent work (arXiv:2207.01954), we showed that a uniformly coupled chain could be symmetrically extended by engineered spin chains in such a way that we could choose part of the spectrum of the overall system. When combined with an…

Quantum Physics · Physics 2022-07-26 Alastair Kay

I report a tight upper bound of the maximum speed of evolution from one quantum state $\rho$ to another $\rho'$ with fidelity $F(\rho,\rho')$ less than or equal to an arbitrary but fixed value under the action of a time-independent…

Quantum Physics · Physics 2013-05-29 H. F. Chau

The ability to coherently transport electron-spin states between different sites of gate-defined semiconductor quantum dots is an essential ingredient for a quantum-dot-based quantum computer. Previous shuttles using electrostatic gating…

Mesoscale and Nanoscale Physics · Physics 2016-07-27 T. A. Baart , N. Jovanovic , C. Reichl , W. Wegscheider , L. M. K. Vandersypen

Certain non-uniformly coupled spin chains can exhibit perfect transfer of quantum states from end to end. Motivated by recent experimental implementations, we extend the simplest such chain to next-to-nearest neighbour (NNN) couplings. It…

Quantum Physics · Physics 2017-10-04 Matthias Christandl , Luc Vinet , Alexei Zhedanov

Quantum state transfer along a one-dimensional spin chain has become a fundamental ingredient for quantum communication between distant nodes in a quantum network. We study the average fidelity of quantum state transfer (QST) along a XY…

Quantum Physics · Physics 2014-07-02 Yang Liu , D. L. Zhou

In this paper, we investigate a high-dimensional quantum state transfer protocol. An arbitrary unknown high-dimensional state can be transferred with high fidelity between two remote registers through a XX coupling spin chain of arbitrary…

Quantum Physics · Physics 2013-04-29 Wei Qin , Chuan Wang , Gui-Lu Long

In this paper we build on the ideas presented in previous works for perfectly transferring a quantum state between opposite ends of a spin chain using a fixed Hamiltonian. While all previous studies have concentrated on nearest-neighbor…

Quantum Physics · Physics 2007-05-23 Alastair Kay

The transmission of quantum states through spin chains is an important element in the implementation of quantum information technologies. Speed and fidelity of transfer are the main objectives which have to be achieved by the devices even…

Quantum Physics · Physics 2015-02-12 Analia Zwick , Gonzalo A. Álvarez , Joachim Stolze , Omar Osenda

We studied the quantum state transfer in randomly coupled spin chains. By using local memories storing the information and dividing the task into transfer portion and decoding portion, conclusive transfer was ingeniously achieved with just…

Quantum Physics · Physics 2007-05-23 Jiankui He , Qing Chen , Lei Ding , Shao-Long Wan

We investigate quantum state transfer in XY spin chains and propose a recursive procedure to construct the nonuniform couplings of these chains with arbitrary length to achieve perfect state transfer(PST). We show that this method is…

Quantum Physics · Physics 2015-05-20 Yaoxiong Wang , Feng Shuang , Herschel Rabitz

We construct the exact solution for a family of one-half spin chains explicitly. The spin chains Hamiltonian corresponds to an isotropic Heisenberg Hamiltonian, with staggered exchange couplings that take only two different values. We work…

Quantum Physics · Physics 2022-10-07 Pablo Serra , Alejandro Ferrón , Omar Osenda

State transfer is a well-known routine for various systems of spins-$\frac{1}2$. Still, it is not well studied for chains of spins of larger magnitudes. In this contribution we argue that while perfect state transfer may seem unnatural in…

Quantum Physics · Physics 2014-01-09 Marcin Wiesniak , Arijit Dutta , Jeonghee Ryu

Efficient quantum-state transfer is achieved in a uniformly coupled spin-1/2 chain, with open boundaries, by application of local magnetic fields on the second and last-but-one spins, respectively. These effective \textit{barriers} induce…

Quantum Physics · Physics 2015-06-12 S. Lorenzo , T. J. G. Apollaro , A. Sindona , F. Plastina

Quantum-state transfer with fidelity higher than 0.99 can be achieved in the ballistic regime of an arbitrarily long one-dimensional chain with uniform nearest-neighbor interaction, except for the two pairs of mirror symmetric extremal…

Quantum Physics · Physics 2012-05-29 T. J. G. Apollaro , L. Banchi , A. Cuccoli , R. Vaia , P. Verrucchi

The XX model with uniform couplings represents the most natural choice for quantum state transfer through spin chains. Given that it has long been established that single-qubit states cannot be transferred with perfect fidelity in this…

Quantum Physics · Physics 2014-12-04 Rúben Sousa , Yasser Omar

Spin chains have been proposed as wires to transport information between distributed registers in a quantum information processor. Unfortunately, the challenges in manufacturing linear chains with engineered couplings has hindered…

Quantum Physics · Physics 2013-06-12 Ashok Ajoy , Paola Cappellaro

We exploit a ferromagnetic chain of interacting $d$-level ($d>2$) particles for arbitrary perfect transfer of quantum states with $(d-1)$ levels. The presence of one extra degree of freedom in the Hilbert space of particles, which is not…

Quantum Physics · Physics 2014-06-04 Abolfazl Bayat

The speed limit of quantum state transfer (QST) in a system of interacting particles is not only important for quantum information processing, but also directly linked to Lieb-Robinson-type bounds that are crucial for understanding various…

Quantum Physics · Physics 2023-11-28 Casey Jameson , Bora Basyildiz , Daniel Moore , Kyle Clark , Zhexuan Gong