English
Related papers

Related papers: Process Tomography for Systems in a Thermal State

200 papers

Transmission spectroscopy, which consists of measuring the wavelength-dependent absorption of starlight by a planet's atmosphere during a transit, is a powerful probe of atmospheric composition. However, the expected signal is typically…

Earth and Planetary Astrophysics · Physics 2015-05-30 N. P. Gibson , S. Aigrain , S. Roberts , T. M. Evans , M. Osborne , F. Pont

A method is proposed that allows one to infer the sum of the values of an observable taken during contacts with a pointer state. Hereby the state of the pointer is updated while contacted with the system and remains unchanged between…

Statistical Mechanics · Physics 2020-11-06 Juzar Thingna , Peter Talkner

Taking accurate measurements of the temperature of quantum systems is a challenging task. The mathematical peculiarities of quantum information make it virtually impossible to measure with infinite precision. In the present paper, we…

Quantum Physics · Physics 2024-08-05 Akira Sone , Diogo O. Soares-Pinto , Sebastian Deffner

We introduce a Gaussian process-based model for handling of non-stationarity. The warping is achieved non-parametrically, through imposing a prior on the relative change of distance between subsequent observation inputs. The model allows…

Machine Learning · Statistics 2019-12-06 David Tolpin

Any optical quantum information processing machine would be comprised of fully-characterized constituent devices for both single state manipulations and tasks involving the interaction between multiple quantum optical states. Ideally for…

Quantum Physics · Physics 2015-05-18 Connor Kupchak , Samuel Rind , Bertus Jordaan , Eden Figueroa

We study an arbitrary non-equilibrium dynamics of a quantum bipartite system coupled to a reservoir. For its characterization, we present a fluctuation theorem (FT) that explicitly addresses the quantum correlation of subsystems during the…

Quantum Physics · Physics 2020-05-22 Jung Jun Park , Hyunchul Nha , Sang Wook Kim , Vlatko Vedral

The linear response to temperature changes is derived for systems with overdamped stochastic dynamics. Holding both in transient and steady state conditions, the results allow to compute nonequilibrium thermal susceptibilities from…

Statistical Mechanics · Physics 2016-04-11 Gianmaria Falasco , Marco Baiesi

For many quantum systems intended for information processing, one detects the logical state of a qubit by integrating a continuously observed quantity over time. For example, ion and atom qubits are typically measured by driving a cycling…

Quantum Physics · Physics 2023-10-03 Shawn Geller , Daniel C. Cole , Scott Glancy , Emanuel Knill

Interacting systems can be studied as the networks where nodes are system units and edges denote correlated interactions. Although percolation on network is a unified way to model the emergence and propagation of correlated behaviours, it…

Statistical Mechanics · Physics 2023-11-15 Yizhou Xu , Pei Sun , Yang Tian

Is it possible to infer the time evolving quantum state of a multichromophoric system from a sequence of two-dimensional electronic spectra (2D-ES) as a function of waiting time? Here we provide a positive answer for a tractable model…

Quantum Physics · Physics 2015-05-27 Joel Yuen-Zhou , Alán Aspuru-Guzik

Estimating the temperature of a cold quantum system is difficult. Usually, one measures a well-understood thermal state and uses that prior knowledge to infer its temperature. In contrast, we introduce a method of thermometry that assumes…

Quantum Physics · Physics 2016-06-07 T. H. Johnson , F. Cosco , M. T. Mitchison , D. Jaksch , S. R. Clark

The real time evolution of two pieces of quantum insulators, initially at different temperatures, is studied when they are glued together. Specifically, each subsystem is taken as a Bose-Hubbard model in a Mott insulator state. The process…

Quantum Gases · Physics 2015-04-28 Mateusz Łącki , Dominique Delande , Jakub Zakrzewski

The optimal state determination (or tomography) is studied for a composite system of two qubits when measurements can be performed on one of the qubits and interactions of the two qubits can be implemented. The goal is to minimize the…

Quantum Physics · Physics 2009-11-13 D. Petz , K. M. Hangos , A. Szanto , F. Szollosi

Understanding relaxation processes is an important unsolved problem in many areas of physics. A key challenge in studying such non-equilibrium dynamics is the scarcity of experimental tools for characterizing their complex transient states.…

We develop an enhanced technique for characterizing quantum optical processes based on probing unknown quantum processes only with coherent states. Our method substantially improves the original proposal [M. Lobino et al., Science 322, 563…

Many processes in chemistry and physics take place on timescales that cannot be explored using standard molecular dynamics simulations. This renders the use of enhanced sampling mandatory. Here we introduce an enhanced sampling method that…

Chemical Physics · Physics 2020-06-12 Jayashrita Debnath , Michele Parrinello

Constructing optimal thermodynamic processes in quantum systems relies on managing the balance between the average excess work and its stochastic fluctuations. Recently it has been shown that two different quantum generalisations of…

Quantum Physics · Physics 2021-12-06 Mohammad Mehboudi , Harry J. D. Miller

Spatio-temporal processes in environmental applications are often assumed to follow a Gaussian model, possibly after some transformation. However, heterogeneity in space and time might have a pattern that will not be accommodated by…

Applications · Statistics 2021-10-15 Thaís C. O. da Fonseca , Viviana G. R. Lobo , Alexandra M. Schmidt

We present a holographic quantum simulation algorithm to variationally prepare thermal states of $d$-dimensional interacting quantum many-body systems, using only enough hardware qubits to represent a ($d$-1)-dimensional cross-section. This…

Quantum Physics · Physics 2022-10-17 Yuxuan Zhang , Shahin Jahanbani , Daoheng Niu , Reza Haghshenas , Andrew C. Potter

In a recent work [10], Poulin and one of us presented a quantum algorithm for preparing thermal Gibbs states of interacting quantum systems. This algorithm is based on Grovers's technique for quantum state engineering, and its running time…

Computational Physics · Physics 2013-06-12 Chen-Fu Chiang , Pawel Wocjan