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Related papers: Non-Markovian memory in a measurement-based quantu…

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We provide a characterization of memory effects in non-Markovian system-bath interactions from a quantum information perspective. More specifically, we establish sufficient conditions for which generalized measures of multipartite quantum,…

Quantum Physics · Physics 2016-05-02 Fagner M. Paula , Paola C. Obando , Marcelo S. Sarandy

Control of the dynamics of an open quantum system is crucial in quantum information processing. Basically there are two ways: one is the control on the system and the other is tuning the bath parameters. In this paper, we use the latter to…

Quantum Physics · Physics 2023-10-16 Arapat Ablimit , Feng-Hua Ren , Run-Hong He , Yang-Yang Xie , Zhao-Ming Wang

We propose a dynamical approach to quantum memories using an oscillator-cavity model. This overcomes the known difficulties of achieving high quantum input-output fidelity with storage times long compared to the input signal duration. We…

Quantum Physics · Physics 2013-05-29 Q. Y. He , M. D. Reid , E. Giacobino , J. Cviklinski , P. D Drummond

Efficient implementation of quantum algorithms requires single- or multi-qubit gates with high fidelity. In this report, we report that the fidelity of single-qubit gate operations on open quantum systems has a maximum value corresponding…

Quantum Physics · Physics 2020-04-29 Nilanjana Chanda , Rangeet Bhattacharyya

Using geometric phases to realize noise-resilient quantum computing is an important method to enhance the control fidelity. In this work, we experimentally realize a universal nonadiabatic geometric quantum gate set in a superconducting…

Although the quality of quantum bits (qubits) and quantum gates has been steadily improving, the available quantity of qubits has increased quite slowly. To address this important issue in quantum computing, we have demonstrated arbitrary…

Quantum Physics · Physics 2016-06-29 Yang Wang , Aishwarya Kumar , Tsung-Yao Wu , David S. Weiss

We provide a quantitative evaluation of non-Markovianity (NM) for an XX chain of interacting qubits with one end coupled to a reservoir. The NM of several non-Markovian spectral densities is assessed in terms of various quantum state…

Quantum Physics · Physics 2023-08-09 G. Mouloudakis , I. Stergou , P. Lambropoulos

Fault-tolerant quantum computing requires extremely precise knowledge and control of qubit dynamics during the application of a gate. We develop a data-driven learning protocol for characterizing quantum gates that builds off previous work…

We employ quantum-volume random-circuit sampling to benchmark the two-QPU entanglement-assisted distributed quantum computing (DQC) and compare it with single-QPU quantum computing. We first specify a single-qubit depolarizing noise model…

Quantum Physics · Physics 2024-06-12 Shao-Hua Hu , George Biswas , Jun-Yi Wu

Randomized benchmarking (RB) protocols have become an essential tool for providing a meaningful partial characterization of experimental quantum operations. While the RB decay rate is known to enable estimates of the average fidelity of…

Quantum Physics · Physics 2018-09-11 Arnaud Carignan-Dugas , Kristine Boone , Joel J. Wallman , Joseph Emerson

Continuous gate sets are a key ingredient for near-term quantum algorithms. Here, we demonstrate a hardware-efficient, continuous set of controlled arbitrary-phase ($\mathrm{C}Z_{\theta}$) gates acting on flux-tunable transmon qubits. This…

A wide class of exact master equations for a multiple qubit system can be explicitly constructed by using the corresponding exact non-Markovian quantum state diffusion equations. These exact master equations arise naturally from the quantum…

Quantum Physics · Physics 2015-03-02 Yusui Chen , J. Q. You , Ting Yu

We examine how dissipation and gate timing errors affect the fidelity of a sequence of SWAP gates on a chain of interacting qubits in comparison to noise in the interqubit interaction. Although interqubit interaction noise and gate timing…

Mesoscale and Nanoscale Physics · Physics 2022-04-18 Nathan L. Foulk , Robert E. Throckmorton , S. Das Sarma

Reducing computational scaling for simulating non-Markovian dissipative dynamics using artificial neural networks is both a major focus and formidable challenge in open quantum systems. To enable neural quantum states (NQSs), we encode…

Quantum Physics · Physics 2026-03-10 Long Cao , Liwei Ge , Daochi Zhang , Xiang Li , Yao Wang , Rui-Xue Xu , YiJing Yan , Xiao Zheng

The realization of fault-tolerant quantum computers hinges on effective quantum error correction protocols, whose performance significantly relies on the nature of the underlying noise. In this work, we directly study the structure of…

Quantum Physics · Physics 2025-07-21 John F Kam , Spiro Gicev , Kavan Modi , Angus Southwell , Muhammad Usman

We present a quantum averaging theory (QAT) for analytically modeling unitary gate dynamics in driven quantum systems beyond the rotating-wave approximation. QAT addresses the simultaneous presence of distinct timescales by generating a…

Quantum Physics · Physics 2026-01-05 Kristian D. Barajas , Wesley C. Campbell

We present measurements of single-qubit gate errors for a superconducting qubit. Results from quantum process tomography and randomized benchmarking are compared with gate errors obtained from a double pi pulse experiment. Randomized…

Mesoscale and Nanoscale Physics · Physics 2009-03-08 J. M. Chow , J. M. Gambetta , L. Tornberg , Jens Koch , Lev S. Bishop , A. A. Houck , B. R. Johnson , L. Frunzio , S. M. Girvin , R. J. Schoelkopf

We give three new algorithms for efficient in-place estimation, without using ancilla qubits, of average fidelity of a quantum logic gate acting on a d-dimensional system using much fewer random bits than what was known so far. Previous…

Quantum Physics · Physics 2019-01-23 Aditya Nema , Pranab Sen

Although quantum circuit depth is commonly used to approximate circuit runtimes, it overlooks a prevailing trait of current hardware implementation: different gates have different execution times. Recognizing the potential for…

Quantum Physics · Physics 2025-09-17 Matthew Tremba , Paul Hovland , Ji Liu

We derive and investigate a general non-Markovian equation for the time-dependence of a Hamiltonian that maximizes the fidelity of a desired quantum gate on any finite-dimensional quantum system in the presence of arbitrary bath and noise…

Quantum Physics · Physics 2016-04-12 Jens Clausen , Guy Bensky , Gershon Kurizki