English
Related papers

Related papers: Phase sensitivity approaching quantum Cramer-Rao b…

200 papers

SU(1,1) interferometer (SUI) is a novel type of interferometer that uses directly entangled quantum fields for sensing phase change. For rotational sensing, Sagnac geometry is usually adopted. However, because SUI depends on the phase sum…

Quantum Physics · Physics 2023-02-15 Wen Zhao , Xuan Tang , Xueshi Guo , Xiaoying Li , Z. Y. Ou

The sensitivity of an atomic interferometer increases when the phase evolution of its quantum superposition state is measured over a longer interrogation interval. In practice, a limit is set by the measurement process, which returns not…

Atomic Physics · Physics 2015-05-05 R. Kohlhaas , A. Bertoldi , E. Cantin , A. Aspect , A. Landragin , P. Bouyer

The Cram\'er-Rao bound captures completely the performance of single-parameter quantum sensors. On the other hand, its extension to multiple parameters demands more caution. Different aspects need to be captured at once, including,…

Quantum Physics · Physics 2026-01-14 Jayanth Jayakumar , Marco Barbieri , Magdalena Stobińska

We report on a novel phase-locking technique for fiber-based Mach-Zehnder interferometers based on discrete single-photon detections, and demonstrate this in a setup. Our interferometer decodes relative-phase-encoded optical pulse pairs for…

Quantum Physics · Physics 2023-11-08 Bastian Hacker , Kevin Günthner , Conrad Rößler , Christoph Marquardt

The super-sensitivity attained in quantum phase estimation is known to be compromised in the presence of decoherence. This is particularly patent at blind spots -- phase values at which sensitivity is totally lost. One remedy is to use a…

Quantum Physics · Physics 2017-10-25 Walker Larson , Bahaa Saleh

Interference is conventionally attributed to path-accumulated phase differences, with measurement treated as a passive readout. Here we demonstrate that single-particle interference is governed by the relative phase between the prepared…

Quantum Physics · Physics 2026-04-21 Tai Hyun Yoon

Sensing and measurement tasks in severely adverse conditions such as loss, noise and dephasing can be improved by illumination with quantum states of light. Previous results have shown a modest reduction in the number of measurements…

Quantum Physics · Physics 2022-02-16 Alex O. C. Davis , Giacomo Sorelli , Valerian Thiel , Brian J. Smith

We provide general bounds of phase estimation sensitivity in linear two-mode interferometers. We consider probe states with a fluctuating total number of particles. With incoherent mixtures of state with different total number of particles,…

Quantum Physics · Physics 2015-06-22 Luca Pezzè , Philipp Hyllus , Augusto Smerzi

Many protocols within quantum cryptography, communications, and computing require the ability to generate entangled states as well as spectral qudits. Nonlinear interferometry is a viable way to engineer these complex quantum states of…

Quantum Physics · Physics 2026-05-19 Cody Charles Payne , Elaganuru Bashaiah , Markus Allgaier

We realize and model a Rydberg-state atom interferometer for measurement of phase and intensity of radio-frequency (RF) electromagnetic waves. A phase reference is supplied to the atoms via a modulated laser beam, enabling atomic…

The quantum noise of light fundamentally limits optical phase sensors. A semiclassical picture attributes this noise to the random arrival time of photons from a coherent light source such as a laser. An engineered source of squeezed states…

Phase is an intrinsic property of light, and thus a crucial parameter across numerous applications in modern optics. Various methods exist for measuring the phase of light, each presenting challenges and limitations-from the mechanical…

Quantum correlation, such as entanglement and squeezing have shown to improve phase estimation in interferometric setups on one side, and non-interferometric imaging scheme of amplitude object on the other. In the last case, quantum…

Sensing with undetected photons allows access to spectral regions with simultaneous detection of photons of another region and is based on nonlinear interferometry. To obtain the full information of a sample, the corresponding interferogram…

Interferometry is a widely-used technique for precision measurements in both classical and quantum contexts. One way to increase the precision of phase measurements, for example in a Mach-Zehnder interferometer (MZI), is to use…

Quantum Physics · Physics 2018-11-07 Stefan Ataman , Anca Preda , Radu Ionicioiu

The recent introduction of coherent optical communications has created a compelling need for ultra-fast phase-sensitive measurement techniques operating at milliwatt peak power levels and in time scales ranging from sub-picoseconds to…

Among the known resources of quantum metrology, one of the most practical and efficient is squeezing. Squeezed states of atoms and light improve the sensing of the phase, magnetic field, polarization, mechanical displacement. They promise…

Quantum Physics · Physics 2021-05-18 Gaetano Frascella , Sascha Agne , Farid Ya. Khalili , Maria V. Chekhova

Stellar intensity interferometers correlate photons within their coherence time and could overcome the baseline limitations of existing amplitude interferometers. Intensity interferometers do not rely on phase coherence of the optical…

Instrumentation and Methods for Astrophysics · Physics 2022-02-24 Sebastian Karl , Andreas Zmija , Stefan Richter , Naomi Vogel , Dmitry Malyshev , Adrian Zink , Thilo Michel , Gisela Anton , Joachim von Zanthier , Stefan Funk

Phase diffusion represents a crucial obstacle towards the implementation of high precision interferometric measurements and phase shift based communication channels. Here we present a nearly optimal interferometric scheme based on homodyne…

Interferometry provides highly sensitive access to optical phase and is central to much of modern metrology and phase imaging methods. Conventional implementations, however, often face trade-offs between mechanical stability and…