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Related papers: Surpassing the Thermal Cramer-Rao Bound with Colli…

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The heat capacity $\mathcal{C}$ of a given probe is a fundamental quantity that determines, among other properties, the maximum precision in temperature estimation. In turn, $\mathcal{C}$ is limited by a quadratic scaling with the number of…

We develop a theory of indirect measurements where a probe is able to read, in short interaction times, the quantum state of a remote system through an incoherent wall. The probe and the system can interact with an ancilla in an incoherent…

Quantum Physics · Physics 2015-05-14 J. Casanova , G. Romero , I. Lizuain , J. C. Retamal , C. F. Roos , J. G. Muga , E. Solano

A two-dimensional three-phase conducting composite with coated circular inclusions, periodically distributed in a parallelogram, is studied. The phases are assumed to be isotropic, and perfect contact conditions at the interfaces are…

Torsional oscillator (TO) is an experimental technique which is widely used to investigate superfluid responses in helium systems confined in porous materials or adsorbed on substrates. In these systems, heat capacity (HC) is also an…

Other Condensed Matter · Physics 2022-02-16 Jun Usami , Ryo Toda , Sachiko Nakamura , Tomohiro Matsui , Hiroshi Fukuyama

In quantum metrology, it is widely believed that the quantum Cramer-Rao bound is attainable bound while it is not true. In order to clarify this point, we explain why the quantum Cramer-Rao bound cannot be attained geometrically. In this…

Quantum Physics · Physics 2016-06-27 Masahito Hayashi , Sai Vinjanampathy , L. C. Kwek

We address quantum critical systems as a resource in quantum estimation and derive the ultimate quantum limits to the precision of any estimator of the coupling parameters. In particular, if L denotes the size of a system and \lambda is the…

Quantum Physics · Physics 2009-11-13 Paolo Zanardi , Matteo G A Paris , Lorenzo Campos Venuti

The problem of estimating a parameter of a quantum system through a series of measurements performed sequentially on a quantum probe is analyzed in the general setting where the underlying statistics is explicitly non-i.i.d. We present a…

Quantum Physics · Physics 2015-12-01 Daniel Burgarth , Vittorio Giovannetti , Airi N. Kato , Kazuya Yuasa

Critical phenomena at finite temperature underpin a broad range of physical systems, yet their study remains challenging due to computational bottlenecks near phase transitions. Quantum annealers have attracted significant interest as a…

Statistical Mechanics · Physics 2025-07-11 Gianluca Teza , Francesco Campaioli , Marco Avesani , Oren Raz

We study the non-equilibrium steady-states of a one-dimensional ($1D1V$) fluid in a finite space region of length $L$. Particles interact among themselves by multi-particle collisions and are in contact with two thermal-wall heat…

Statistical Mechanics · Physics 2021-03-08 Stefano Lepri , Guido Ciraolo , Pierfrancesco Di Cintio , Jamie Gunn , Roberto Livi

Many protocols require precise rotation measurement. Here we present a general class of states that surpass the shot noise limit for measuring rotation around arbitrary axes. We then derive a quantum Cram\'er-Rao bound for simultaneously…

Quantum Physics · Physics 2019-03-20 Aaron Z. Goldberg , Daniel F. V. James

The ratio of the symmetry energy coefficient to temperature, $a_sym/T$, in Fermi energy heavy ion collisions, has been experimentally extracted as a function of the fragment atomic number using isoscaling parameters and the variance of the…

Nuclear Experiment · Physics 2014-11-20 Z. Chen , S. Kowalski , M. Huang , R. Wada , T. Keutgen , K. Hagel , J. Wang , L. Qin , J. B. Natowitz , T. Materna , P. K. Sahu , A. Bonasera

Accurate temperature estimation in the quantum and cryogenic regimes remains a fundamental challenge. Here, we investigate nonequilibrium quantum thermometry using a single-qubit probe coupled to a bosonic bath through noncommuting…

Quantum Physics · Physics 2025-12-23 Youssef Aiache , Abderrahim El Allati , İlkay Demir , Khadija El Anouz

The second-order anti-coherent state of light is known to saturate the Cramer-Rao Bound (QCRB) for rotation sensing around an arbitrary axis. However, due to the complexity of the state and the inefficiency of state tomography, parameter…

Quantum Physics · Physics 2026-05-26 Zhuoran Bao , Daniel F. V. James

We show how to measure the order-two Renyi entropy of many-body states of spinful fermionic atoms in an optical lattice in equilibrium and non-equilibrium situations. The proposed scheme relies on the possibility to produce and couple two…

Quantum Gases · Physics 2013-06-10 Hannes Pichler , Lars Bonnes , Andrew J. Daley , Andreas M. Läuchli , Peter Zoller

Spontaneous symmetry breaking is a hallmark of equilibrium systems, typically characterized by a single critical point separating ordered and disordered phases. Recently, a novel class of non-equilibrium phase transitions was uncovered…

Statistical Mechanics · Physics 2025-12-16 Gustavo A. L. Forão , Jonas Berx , Tan Van Vu , Carlos E. Fiore

We study the collective phenomena and constraints associated with the aggregation of individual cooling units from a statistical mechanics perspective. These units are modelled as Thermostatically Controlled Loads (TCLs) and represent zones…

Physics and Society · Physics 2022-08-30 Lucas Fuentes Valenzuela , Lindell Williams , Michael Chertkov

We discuss the Heisenberg limit in the multiparameter metrology within two different paradigms -- the one, where the measurement is repeated many times (so the Cram\'er-Rao bound is guaranteed to be asymptotically saturable) and the second…

Quantum Physics · Physics 2022-09-16 Wojciech Górecki , Rafał Demkowicz-Dobrzański

In multiparameter quantum metrology, the weighted-arithmetic-mean error of estimation is often used as a scalar cost function to be minimized during design optimization. However, other types of mean error can reveal different facets of…

Quantum Physics · Physics 2020-02-12 Xiao-Ming Lu , Zhihao Ma , Chengjie Zhang

We introduce a new kind of quantum measurement that is defined to be symmetric in the sense of uniform Fisher information across a set of parameters that injectively represent pure quantum states in the neighborhood of a fiducial pure…

Quantum Physics · Physics 2016-05-11 Nan Li , Christopher Ferrie , Jonathan A. Gross , Amir Kalev , Carlton M. Caves

The amount of extractable work from a physical system is fundamentally connected to the information available about its state, as illustrated by Maxwell's demon and the Gibbs paradox. In standard thermodynamic protocols involving…

Quantum Physics · Physics 2026-02-27 Tanmoy Biswas