English
Related papers

Related papers: Continuous Force and Displacement Measurement Belo…

200 papers

Quantum metrology aims to enhance measurement precision beyond the standard quantum limit (SQL), the benchmark set by classical resources, enabling advances in sensing, imaging, and fundamental physics. A critical milestone beyond the SQL…

Quantum Physics · Physics 2025-08-19 Kimin Park , Tanjung Krisnanda , Yvonne Gao , Radim Filip

Quantum entanglement and quantum squeezing are two most typical approaches to beat the standard quantum limit (SQL) of the sensitive phase estimations in quantum metrology. Each of them has already been utilized individually to improve the…

Quantum Physics · Physics 2023-08-28 X. N. Feng , M. Zhang , L. F. Wei

In this paper, we show how the Robertson uncertainty relation gives certain intrinsic quantum limits of measurements in the most general and rigorous mathematical treatment. A general lower bound for the product of the root-mean-square…

Quantum Physics · Physics 2015-05-20 Masanao Ozawa

The Standard Quantum Limit (SQL) for the measurement of a free mass position is illustrated, along with two necessary conditions for breaching it. A measurement scheme that overcomes the SQL is engineered. It can be achieved in three-steps:…

Quantum Physics · Physics 2007-05-23 G. M. D'Ariano , M. F. Sacchi , R. Seno

Standard Quantum Limit (SQL) of a classical mechanical force detection results from quantum back action impinged by the meter on a probe mechanical transducer perturbed by the force of interest. In this paper we introduce a technique of…

Quantum Physics · Physics 2021-09-01 Sergey P. Vyatchanin , Albert I. Nazmiev , Andrey B. Matsko

Optomechanical detectors have reached the standard quantum limit in position and force sensing where measurement backaction noise starts to be the limiting factor for the sensitivity. A strategy to circumvent measurement backaction, and…

Quantum Physics · Physics 2014-06-11 Maximilian H. Wimmer , Daniel Steinmeyer , Klemens Hammerer , Michèle Heurs

Quantum-enhanced measurements use highly non-classical quantum states in order to enhance the precision of the measurement of classical quantities, like the length of an optical cavity. The major goal is to beat the standard quantum limit…

Quantum Physics · Physics 2009-05-29 Daniel Braun , John Martin

Quantum noise limits the sensitivity of interferometric measurements. It is generally admitted that it leads to an ultimate sensitivity, the ``standard quantum limit''. Using a semi-classical analysis of quantum noise, we show that a…

Quantum Physics · Physics 2010-11-01 Marc-Thierry Jaekel , Serge Reynaud

In quantum metrology, entanglement represents a valuable resource that can be used to overcome the Standard Quantum Limit (SQL) that bounds the precision of sensors that operate with independent particles. Measurements beyond the SQL are…

Quantum-enhanced measurements use quantum mechanical effects in order to enhance the sensitivity of the measurement of classical quantities, such as the length of an optical cavity. The major goal is to beat the standard quantum limit…

Quantum Physics · Physics 2011-03-10 Daniel Braun , John Martin

We introduce a new method for error-corrected quantum metrology where only partial quantum error correction (QEC) is needed to suppress local noise and maintain the probe states' super-standard-quantum-limit (super-SQL) sensing performance.…

Quantum Physics · Physics 2026-05-12 Yinan Chen , Zongyuan Wang , Sisi Zhou

The low-noise amplification of weak microwave signals is crucial for countless protocols in quantum information processing. Quantum mechanics sets an ultimate lower limit of half a photon to the added input noise for phase-preserving…

The measurement result of the moved distance for a free mass m during the time t between two position measurements cannot be predicted with uncertainty smaller than sqrt{hbar t/2m}. This is formulated as a standard quantum limit (SQL) and…

Quantum Physics · Physics 2013-05-29 Seiji Kosugi

Broadband multidimensional variational measurement allows to overcome Standard Quantum Limit (SQL) of a classical mechanical force detection, resulting from quantum back action, which perturbs evolution of a mechanical oscillator. In this…

Quantum Physics · Physics 2023-10-10 Aleksandr A. Movsisian , Sergey P. Vyatchanin

In the quest to develop viable designs for third-generation optical interferometric gravitational-wave detectors (e.g., LIGO-III and EURO), one strategy is to monitor the relative momentum or speed of the test-mass mirrors, rather than…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Patricia Purdue , Yanbei Chen

Optomechanical sensors are capable of transducing external perturbations to resolvable optical signals. A particular regime of interest is that of high-bandwidth force detection, where an impulse is delivered to the system over a short…

The typical bound on parameter estimation, known as the standard quantum limit (SQL), can be surpassed by exploiting quantum resources such as entanglement. To estimate the magnetic probe field, we propose a quantum sensor based on a…

Quantum Physics · Physics 2025-07-01 Monika Mothsara , Leela Ganesh Chandra Lakkaraju , Srijon Ghosh , Aditi Sen De

In their paper "Entanglement-enhanced matter-wave interferometry in a high-finesse cavity" Nature (2022), Greve et. al. claim to use entanglement in a matter-wave interferometer to achieve a sensitivity beyond that achievable with the same…

Quantum Physics · Physics 2023-05-04 Liam P. McGuinness

Quantum metrology allows us to attain a measurement precision that surpasses the classically achievable limit by using quantum characters. The metrology precision is raised from the standard quantum limit (SQL) to the Heisenberg limit (HL)…

Quantum Physics · Physics 2017-11-21 Yuan-Sheng Wang , Chong Chen , Jun-Hong An

We present a design for a new microresonator whose geometry is optimized to maximize sub-Standard Quantum Limit (SQL) performance. The new design is predicted to have thermal noise well below the SQL across a broad range of frequencies when…