English
Related papers

Related papers: Simulating a single qubit channel using a mixed st…

200 papers

Decoherence is a fundamental obstacle to the implementation of large-scale and low-noise quantum information processing devices. In this work, we suggest an approach for suppressing errors by employing pre-processing and post-processing…

Quantum Physics · Physics 2020-02-25 E. O. Kiktenko , A. S. Mastiukova , A. K. Fedorov

Absolutely maximally entangled states are quantum states that exhibit maximal entanglement across any bipartition, making them valuable for applications. This study investigates the behavior of qubit AME states under the influence of noisy…

Quantum Physics · Physics 2025-05-13 Maria Stawska , Jan Wójcik , Andrzej Grudka , Antoni Wójcik

We develop a device-independent framework for testing quantum channels. That is, we falsify a hypothesis about a quantum channel based only on an observed set of input-output correlations. Formally, the problem consists of characterizing…

Quantum Physics · Physics 2017-03-17 Michele Dall'Arno , Sarah Brandsen , Francesco Buscemi

We report an experimental realization of one-way quantum computing on a two-photon four-qubit cluster state. This is accomplished by developing a two-photon cluster state source entangled both in polarization and spatial modes. With this…

Quantum Physics · Physics 2012-10-30 Kai Chen , Che-Ming Li , Qiang Zhang , Yu-Ao Chen , Alexander Goebel , Shuai Chen , Alois Mair , Jian-Wei Pan

Using the tensor product representation in the density matrix renormalization group, we show that a quantum circuit of Grover's algorithm, which has one-qubit unitary gates, generalized Toffoli gates, and projective measurements, can be…

Quantum Physics · Physics 2007-05-23 A. Kawaguchi , K. Shimizu , Y. Tokura , N. Imoto

The evolution of a quantum system interacting with an environment can be described as a unitary process acting on both the system and the environment. In this framework, the system's evolution can be predicted by tracing out the…

We present a protocol to simulate the correlations implied by nonmaximally entangled two qubit states. We extend this protocol to simulate the non-local part of these correlations. These protocols use single cbit communication and a single…

Quantum Physics · Physics 2008-07-15 Ali Ahanj , Pramod S. Joag

The evolution of an open system is usually associated with the interaction of the system with an environment. A new method to study the open-type system evolution of a qubit (two-level atom) state is established. This evolution is…

We develop and demonstrate methods for simulating the scattering of particle wave packets in the interacting Thirring model on digital quantum computers, with hardware implementations on up to 80 qubits. We identify low-entanglement time…

We report on two optical realizations of the $1 \to 2$ asymmetric phase-covariant cloning machines for polarization states of single photons. The experimental setups combine two-photon interference and tunable polarization filtering that…

Quantum Physics · Physics 2009-11-13 Jan Soubusta , Lucie Bartuskova , Antonin Cernoch , Miloslav Dusek , Jaromir Fiurasek

It is well known that qubits immersed in a squeezed vacuum environment exhibit many exotic phenomena, including dissipative entanglement stabilization. Here, we show that these effects only require interference between excitation and decay…

Quantum Physics · Physics 2023-07-25 L. C. G. Govia , A. Lingenfelter , A. A. Clerk

We address the propagation of a single photon pulse with two polarization components, i.e., a polarization qubit, in an inhomogeneously broadened "phaseonium" \Lambda-type three-level medium. We combine some of the non-trivial propagation…

Quantum Physics · Physics 2012-04-13 D. Viscor , A. Ferraro , Yu. Loiko , J. Mompart , V. Ahufinger

Channel-state duality is a central result in quantum information science. It refers to the correspondence between a dynamical process (quantum channel) and a static quantum state in an enlarged Hilbert space. Since the corresponding dual…

Quantum Physics · Physics 2022-10-10 Bin Yan , Nikolai A. Sinitsyn

Given multiple copies of a mixed quantum state with an unknown, nondegenerate principal eigenspace, quantum state purification is the task of recovering a quantum state that is closer to the principal eigenstate. A streaming protocol…

Quantum Physics · Physics 2025-03-31 Daniel Grier , Debbie Leung , Zhi Li , Hakop Pashayan , Luke Schaeffer

Quantum non-Markovianity of channels can be produced by mixing Markovian channels, as observed recently by various authors. We consider an analogous question of whether singularities of the channel can be produced by mixing non-singular…

Quantum Physics · Physics 2021-04-21 Shrikant Utagi , Vinod N. Rao , R. Srikanth , Subhashish Banerjee

We study extensions of a quantum channel whose one-way capacities are described by a single-letter formula. This provides a simple technique for generating powerful upper bounds on the capacities of a general quantum channel. We apply this…

Quantum Physics · Physics 2009-02-20 Graeme Smith , John A. Smolin

We propose a framework for Quantum Field Theory (QFT) studies that allows us to represent field excitations as quantum channels. We demonstrate inner-workings of the proposed scheme for two universal states: the regularized vacuum state of…

High Energy Physics - Theory · Physics 2023-07-26 Michal Baczyk

Using the recent ability of quantum computers to initialize quantum states rapidly with high fidelity, we use a function operating on a discrete set to create a simple class of quantum channels. Fixed points and periodic orbits, that are…

Quantum Physics · Physics 2023-08-25 A. C. Quillen , Nathan Skerrett

Unitary t-designs have a wide variety of applications in quantum information theory, such as quantum data encryption and randomised benchmarking. However, experimental realisations of t-designs are subject to noise. Here we investigate the…

Quantum Physics · Physics 2024-03-18 Conrad Strydom , Mark Tame

Quantum teleportation of a n-qubit state performed using as entangled resource a general bipartite state of 2n qubits instead of n Bell states is equivalent to a correlated Pauli channel. This provides a new characterization of such…

Quantum Physics · Physics 2010-01-15 Filippo Caruso , Vittorio Giovannetti , G. Massimo Palma