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In this paper we introduce a novel noise model for quantum measurements motivated by an indirect measurement scheme with faulty preparation. Averaging over random dynamics governing the interaction between the quantum system and a probe, a…

Quantum Physics · Physics 2025-07-17 Faedi Loulidi , Ion Nechita , Clément Pellegrini

The ability to use quantum technology to achieve useful tasks, be they scientific or industry related, boils down to precise quantum control. In general it is difficult to assess a proposed solution due to the difficulties in characterising…

Quantum Physics · Physics 2020-12-07 Akram Youssry , Gerardo A. Paz-Silva , Christopher Ferrie

Classical sensors for spectrum analysis are widely used but lack micro- or nanoscale spatial resolution. On the other hand, quantum sensors, capable of working with nanoscale precision, do not provide precise frequency resolution over a…

Quantum Physics · Physics 2022-07-12 Nicolas Staudenmaier , Simon Schmitt , Liam P. McGuinness , Fedor Jelezko

We develop theoretically and demonstrate experimentally a universal dynamical decoupling method for robust quantum sensing with unambiguous signal identification. Our method uses randomisation of control pulses to suppress simultaneously…

Quantum metrology with entangled states in realistic noisy environments always suffers from decoherence. Therefore, the measurement precision is greatly reduced. Here we applied the dynamical decoupling method to protect the $N$-qubit…

Quantum Physics · Physics 2016-12-21 Yang Dong , Xiang-Dong Chen , Guang-Can Guo , Fang-Wen Sun

Decoherence and imperfect control are crucial challenges for quantum technologies. Common protection strategies rely on noise temporal autocorrelation, which is not optimal if other correlations are present. We develop and demonstrate…

Quantum Physics · Physics 2026-01-28 Alon Salhov , Qingyun Cao , Jianming Cai , Alex Retzker , Fedor Jelezko , Genko Genov

Quantum advantage requires overcoming noise-induced degradation of quantum systems. Conventional methods for reducing noise such as error mitigation face scalability issues in deep circuits. Specifically, noise hampers the extraction of…

Quantum Physics · Physics 2023-12-05 Yonglong Ding , Ruyu Yang

Preserving coherence long enough to perform meaningful calculations is one of the major challenges on the pathway to large scale quantum computer implementations. Noise coupled from the environment is the main contributing factor to…

Sensors that harness exclusively quantum phenomena (such as entanglement) can achieve superior performance compared to those employing only classical principles. Recently, a technique based on postselected, weakly-performed measurements has…

Quantum Physics · Physics 2013-01-18 George C. Knee , G. Andrew D. Briggs , Simon C. Benjamin , Erik M. Gauger

Mitigating noise-induced decoherence is the central challenge in controlling open quantum systems. While existing robust protocols often require precise noise models, we introduce a universal framework for noise-agnostic quantum control…

Quantum Physics · Physics 2026-03-18 Lixiang Ding , Jingtao Fan , Xingze Qiu

In this paper, we introduce a novel authentication scheme for satellite nodes based on quantum entanglement and measurement noise profiles. Our approach leverages the unique noise characteristics exhibited by each satellite's quantum…

Quantum Physics · Physics 2025-01-14 Pooria Madani , Carolyn McGregor

A method is proposed for obtaining the spectrum for noise that causes the phase decoherence of a qubit directly from experimentally available data. The method is based on a simple relationship between the spectrum and the coherence time of…

Quantum Physics · Physics 2015-05-28 Tatsuro Yuge , Susumu Sasaki , Yoshiro Hirayama

Quantum-dense metrology (QDM) constitutes a special case of quantum metrology in which two orthogonal phase space projections of a signal are simultaneously sensed beyond the shot noise limit. Previously it was shown that the additional…

Quantum Physics · Physics 2016-11-02 Melanie Ast , Sebastian Steinlechner , Roman Schnabel

A qubit subjected to pure dephasing due to classical Gaussian noise can be turned into a spectrometer of this noise by utilizing its readout under properly chosen dynamical decoupling (DD) sequences to reconstruct the power spectral density…

Mesoscale and Nanoscale Physics · Physics 2017-07-25 Piotr Szańkowski , Guy Ramon , Jan Krzywda , Damian Kwiatkowski , Łukasz Cywiński

System noise identification is crucial to the engineering of robust quantum systems. Although existing quantum noise spectroscopy (QNS) protocols measure an aggregate amount of noise affecting a quantum system, they generally cannot…

Nitrogen vacancy (NV) centers in diamond are atom-scale defects with long spin coherence times that can be used to sense magnetic fields with high sensitivity and spatial resolution. Typically, the magnetic field projection at a single…

Nuclear magnetic resonance (NMR) spectroscopy provides unparalleled access to molecular structure and dynamics but is traditionally limited by weak signal strength, requiring large sample volumes and high magnetic fields. Here, we…

Applied Physics · Physics 2026-04-29 Dileep Singh , Riley W. Hooper , Christoph Findler , Utsab Banerjee , Dominik B. Bucher

Nitrogen-vacancy centers in diamond allow measurement of environment properties such as temperature, magnetic and electric fields at nanoscale level, of utmost relevance for several research fields, ranging from nanotechnologies to…

Exploring the noise spectrum impacting a qubit and extending its coherence duration are fundamental components of quantum technologies. In this study, we introduce parametric spectroscopy, a method that merges parametric modulation of a…

Quantum Physics · Physics 2025-03-10 Nir Gavrielov , Santiago Oviedo-Casado , Alex Retzker

Quantum noise fundamentally limits the utility of near-term quantum devices, making error mitigation essential for practical quantum computation. While traditional quantum error correction codes require substantial qubit overhead and…

Quantum Physics · Physics 2025-09-23 Karan Kendre