English
Related papers

Related papers: Threshold for a discrete-variable sensor of quantu…

200 papers

Quantum sensors leverage nonclassical resources to achieve sensing precision at the Heisenberg limit, surpassing the standard quantum limit attainable through classical strategies. However, a critical issue is that the environmental noise…

Quantum Physics · Physics 2025-11-24 Hang Xu , Tailong Xiao , Jingzheng Huang , Jianping Fan , Guihua Zeng

The performance of a quantum sensor is fundamentally limited by noise. This noise is particularly damaging when it becomes correlated with the readout of a target signal, caused by fluctuations of the sensor's operating parameters. These…

Quantum metrology utilizes entanglement for improving the sensitivity of measurements. Up to now the focus has been on the measurement of just one out of two non-commuting observables. Here we demonstrate a laser interferometer that…

Quantum sensors hold considerable promise for precision measurement, yet their capabilities are inherently constrained by environmental noise. A fundamental task in quantum sensing is determining the precision limit of noisy sensor devices.…

Quantum Physics · Physics 2026-04-14 Dayou Yang , Moulik Ketkar , Koenraad Audenaert , Susana F. Huelga , Martin B. Plenio

The states needed in a quantum computation are extremely affected by decoherence. Several methods have been proposed to control error spreading. They use two main tools: fault-tolerant constructions and concatenated quantum error correcting…

Quantum Physics · Physics 2007-05-23 Pedro J. Salas , Angel L. Sanz

The signal to noise ratio of quantum sensing protocols scales with the square root of the coherence time. Thus, increasing this time is a key goal in the field. Dynamical decoupling has proven to be efficient in prolonging the coherence…

Quantum Physics · Physics 2015-06-17 Gilad Arrad , Yuval Vinkler , Dorit Aharonov , Alex Retzker

Quantum sensors have the potential to outperform their classical counterparts. For classical sensing, the uncertainty of the estimation of the target fields scales inversely with the square root of the measurement time T. On the other hand,…

Quantum Physics · Physics 2018-05-09 Yuichiro Matsuzaki , Simon Benjamin , Shojun Nakayama , Shiro Saito , William J. Munro

Quantum coherence is the key resource for quantum technology, with applications in quantum optics, information processing, metrology and cryptography. Yet, there is no universally efficient method for quantifying coherence either in…

Quantum Physics · Physics 2014-10-24 Davide Girolami

The sensitivity of classical and quantum sensing is impaired in a noisy environment. Thus, one of the main challenges facing sensing protocols is to reduce the noise while preserving the signal. State of the art quantum sensing protocols…

Optics · Physics 2016-07-18 L. Cohen , Y. Pilnyak , D. Istrati , A. Retzker , H. S. Eisenberg

"Quantum sensing" describes the use of a quantum system, quantum properties or quantum phenomena to perform a measurement of a physical quantity. Historical examples of quantum sensors include magnetometers based on superconducting quantum…

Quantum Physics · Physics 2017-08-31 C. L. Degen , F. Reinhard , P. Cappellaro

Quantum metrology has many important applications in science and technology, ranging from frequency spectroscopy to gravitational wave detection. Quantum mechanics imposes a fundamental limit on measurement precision, called the Heisenberg…

Quantum Physics · Physics 2018-02-05 Sisi Zhou , Mengzhen Zhang , John Preskill , Liang Jiang

Detecting and characterizing decoherence-inducing noise sources is critical for developing robust quantum technologies and deploying quantum sensors operating at molecular scales. However, current noise spectroscopies rely on severe…

Quantum Physics · Physics 2025-07-09 Nanako Shitara , Andrés Montoya-Castillo

Novel concepts, perspectives and challenges in measuring and controlling an open quantum system via sequential schemes are shown. We discuss how similar protocols, relying both on repeated quantum measurements and dynamical decoupling…

Quantum Physics · Physics 2019-06-26 Stefano Gherardini , Andrea Smirne , Matthias M. Müller , Filippo Caruso

Making use of coherence and entanglement as metrological quantum resources allows to improve the measurement precision from the shot-noise- or quantum limit to the Heisenberg limit. Quantum metrology then relies on the availability of…

Quantum reservoir computing offers a promising approach to the utilization of complex quantum dynamics in machine learning. Statistical noise inevitably arises in real settings of quantum reservoir computing (QRC) due to the practical…

Quantum Physics · Physics 2026-04-23 Youssef Kora , Christoph Simon

Entangled many-body states enable high-precision quantum sensing beyond the standard quantum limit. We develop interferometric sensing protocols based on quantum critical wavefunctions and compare their performance with…

Quantum Physics · Physics 2026-01-09 Yinan Chen , Sara Murciano , Pablo Sala , Jason Alicea

Decoherence is the main obstacle to quantum computation. The decoherence rate per qubit is typically assumed to be constant. It is known, however, that quantum registers coupling to a single reservoir can show a decoherence rate per qubit…

Quantum Physics · Physics 2020-05-20 Joris Kattemölle , Jasper van Wezel

The sensitivity afforded by quantum sensors is limited by decoherence. Quantum error correction (QEC) can enhance sensitivity by suppressing decoherence, but it has a side-effect: it biases a sensor's output in realistic settings. If…

Quantum Physics · Physics 2022-04-20 Ivan Rojkov , David Layden , Paola Cappellaro , Jonathan Home , Florentin Reiter

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

Quantum entanglement, in the form of spin squeezing, is known to improve the sensitivity of atomic sensors to static or slowly varying fields. Sensing transient events presents a distinct challenge, requires different analysis tools, and…

Quantum Physics · Physics 2025-12-08 Julia Amoros-Binefa