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Related papers: Quantum Filtering for Squeezed Noise Inputs

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The use of quantum stochastic models is widespread in dynamical reduction, simulation of open systems, feedback control and adaptive estimation. In many applications only part of the information contained in the filter's state is actually…

Quantum Physics · Physics 2025-10-01 Tommaso Grigoletto , Clément Pellegrini , Francesco Ticozzi

As quantum machine learning continues to develop at a rapid pace, the importance of ensuring the robustness and efficiency of quantum algorithms cannot be overstated. Our research presents an analysis of quantum randomized smoothing, how…

Quantum Physics · Physics 2024-07-26 Nicola Franco , Marie Kempkes , Jakob Spiegelberg , Jeanette Miriam Lorenz

In our work, we show how, for a network of bosonic modes, canonical commutation relations constrain the coefficients relating input and internal modes. Based on these constraints, we derive a lower bound on the total steady-state squeezing…

Quantum Physics · Physics 2026-04-27 Xin Zhou , Francesco Massel

We present a supervised machine learning-based method using convolutional neural networks to estimate the covariance matrix of Gaussian quantum states in the presence of thermal noise. Unlike computationally intensive density matrix…

We consider the quantum (trajectories) filtering equation for the case when the system is driven by Bose field inputs prepared in an arbitrary non-zero mean Gaussian state. The a posteriori evolution of the system is conditioned by the…

Quantum Physics · Physics 2016-04-11 Anita Dąbrowska , John Gough

Coupled optical cavities, which support normal modes, play a critical role in optical filtering, sensing, slow-light generation, and quantum state manipulation. Recent theoretical work has proposed incorporating nonlinear materials into…

Motivated by successful classical models for noise reduction, we suggest a quantum technique for filtering noise out of quantum states. The purpose of this paper is twofold: presenting a simple construction of quantum cross-correlations…

Quantum Physics · Physics 2017-11-27 Boaz Tamir , Eliahu Cohen

We introduce a theoretical framework for resource-efficient characterization and control of non-Markovian open quantum systems, which naturally allows for the integration of given, experimentally motivated, control capabilities and…

In quantum reading, a quantum state of light (transmitter) is applied to read classical information. In the presence of noise or for sufficiently weak signals, quantum reading can outperform classical reading by enhanced state…

Quantum Physics · Physics 2015-01-22 Wojciech Roga , Daniela Buono , Fabrizio Illuminati

Quantum state smoothing is a technique for assigning a valid quantum state to a partially observed dynamical system, using measurement records both prior and posterior to an estimation time. We show that the technique is greatly simplified…

Quantum Physics · Physics 2025-09-09 Kiarn T. Laverick , Areeya Chantasri , Howard M. Wiseman

Adaptive filtering is a powerful class of control theoretic concepts useful in extracting information from noisy data sets or performing forward prediction in time for a dynamic system. The broad utilization of the associated algorithms…

Quantum Physics · Physics 2021-07-21 Riddhi S. Gupta , Michael J. Biercuk

In this article, based on some simple and reasonable assumptions, we derive a Gaussian noise model for quantum amplitude estimation. We provide results from quantum amplitude estimation run on various IBM superconducting quantum computers…

Quantum Physics · Physics 2024-11-08 Steven Herbert , Ifan Williams , Roland Guichard , Darren Ng

Quantum systems are exceedingly difficult to engineer because they are sensitive to various types of noises. In particular, time-dependent noises are frequently encountered in experiments but how to overcome them remains a challenging…

Quantum Physics · Physics 2022-05-06 Xiaodong Yang , Xinfang Nie , Tao Xin , Dawei Lu , Jun Li

Quantum metrology promises precision beyond classical limits, yet environmental noise typically degrades the quantum resources required for such enhancement. In this work, we investigate frequency estimation in noisy continuous-variable…

Quantum Physics · Physics 2026-05-08 Ayan Patra , Manju , Aditi Sen De , Matteo G. A. Paris

Quantum systems of interest are typically coupled to several quantum channels (more generally environments). In this paper, we develop an exact stochastic Schr\"{o}dinger equation for an open quantum system coupled to a hybrid environment…

Quantum Physics · Physics 2017-05-11 Xinyu Zhao , Wufu Shi , J. Q. You , Ting Yu

When simulating the dynamics of open quantum systems with quantum computers, it is essential to accurately approximate the system's behaviour while preserving the physicality of its evolution. Traditionally, for Markovian open quantum…

Quantum Physics · Physics 2025-12-18 I. J. David , I. Sinayskiy , F. Petruccione

Noise is ubiquitous in real quantum systems, leading to non-Hermitian quantum dynamics, and may affect the fundamental states of matter. Here we report in experiment a quantum simulation of the two-dimensional non-Hermitian quantum…

Quantum Physics · Physics 2022-07-01 Zidong Lin , Lin Zhang , Xinyue Long , Yu-ang Fan , Yishan Li , Kai Tang , Jun Li , XinFang Nie , Tao Xin , Xiong-Jun Liu , Dawei Lu

Simulating open quantum systems on quantum computers presents a fundamental challenge: open quantum dynamics are intrinsically nonunitary, whereas quantum computers operate through unitary evolution. Conventional approaches overcome this…

Quantum Physics · Physics 2025-10-27 Sameer Dambal , Akira Sone , Yu Zhang

We develop a theory of quantum fluctuations and squeezing in a three-dimensional Bose-Einstein condensate atom interferometer with nonlinear losses. We use stochastic equations in a truncated Wigner representation to treat quantum noise.…

Quantum Gases · Physics 2013-02-21 B. Opanchuk , M. Egorov , S. Hoffmann , A. Sidorov , P. D. Drummond

We study the quantum noise in the harmonic mode of a singly resonant frequency doubler simultaneously driven in both modes. This simple extension of the frequency doubler greatly improves its performance as a bright squeezed light source.…

Quantum Physics · Physics 2016-09-08 C. Cabrillo , J. L. Roldan , P. Garcia-Fernandez