English
Related papers

Related papers: Quantum probing beyond pure dephasing

200 papers

We consider measurement-based quantum computation using the state of a spin-lattice system in equilibrium with a thermal bath and free to evolve under its own Hamiltonian. Any single qubit measurements disturb the system from equilibrium…

Quantum Physics · Physics 2009-09-23 David Jennings , Andrzej Dragan , Sean D. Barrett , Stephen D. Bartlett , Terry Rudolph

Decoherence is a manifestation of the coupling of a system with its environment. The resulting loss of information can hamper the functioning of quantum devices, hence the need of understanding its origin and dynamics. Decoherence can stem…

In realistic metrology, entangled probes are more sensitive to noise, especially for a correlated environment. The precision of parameter estimation with entangled probes is even lower than that of the unentangled ones in a correlated…

Quantum Physics · Physics 2021-12-22 Wan-Ting He , Huan-Yu Guang , Zi-Yun Li , Ru-Qiong Deng , Na-Na Zhang , Jie-Xing Zhao , Fu-Guo Deng , Qing Ai

The qubit (or a system of two quantum dots) has become a standard paradigm for studying quantum information processes. Our focus is Decoherence due to interaction of the qubit with its environment, leading to noise. We consider quantum…

Mesoscale and Nanoscale Physics · Physics 2015-05-27 Ebad Kamil , Sushanta Dattagupta

The precise measurement of low temperatures is significant for both the fundamental understanding of physical processes and technological applications. In this work, we present a method for low-temperature measurement that improves thermal…

Quantum Physics · Physics 2024-04-23 Asghar Ullah , M. Tahir Naseem , Özgür E. Müstecaplıoğlu

Perturbation theory in quantum mechanics studies how quantum systems interact with their environmental perturbations. Harmonic perturbation is a rare special case of time-dependent perturbations in which exact analysis exists. Some…

Quantum Physics · Physics 2008-01-01 Jie-Hong R. Jiang , Dah-Wei Chiou , Cheng-En Wu

Decoherence is one of the most important obstacles that must be overcome in quantum information processing. It depends on the qubit-environment coupling strength, but also on the spectral composition of the noise generated by the…

Quantum Physics · Physics 2011-12-02 Gonzalo A. Alvarez , Dieter Suter

Engineering, controlling, and simulating quantum dynamics is a strenuous task. However, these techniques are crucial to develop quantum technologies, preserve quantum properties, and engineer decoherence. Earlier results have demonstrated…

Quantum simulation is a potentially powerful application of quantum computing, holding the promise to be able to emulate interesting quantum systems beyond the reach of classical computing methods. Despite such promising applications, and…

Quantum Physics · Physics 2022-10-07 Kaelyn J. Ferris , A. J. Rasmusson , Nicholas T. Bronn , Olivia Lanes

The unknown temperature of a sample may be estimated with minimal disturbance by putting it in thermal contact with an individual quantum probe. If the interaction time is sufficiently long so that the probe thermalizes, the temperature can…

Quantum Physics · Physics 2015-06-09 Luis A. Correa , Mohammad Mehboudi , Gerardo Adesso , Anna Sanpera

Quantum illumination leverages entangled lights to detect the presence of low-reflectivity objects within a thermal environment. In a related vein, quantum parameter estimation utilizes nonclassical probes to precisely determine unknown…

Quantum Physics · Physics 2025-06-18 Wei Zhong , Dong-Qing Wang , Wen-Yi Zhu , Lan Zhou , Ming-Ming Du , Yu-Bo Sheng

In quantum theory, the inescapable interaction between a system and its surroundings would lead to a loss of coherence and leakage of information into the environment. An effective approach to retain the quantum characteristics of the…

Quantum Physics · Physics 2025-08-29 Guohui Dong , Yao Yao

We show that in presence of a local and uncorrelated dephasing noise, quantum advantage can be obtained in the Fisher information-based lower bound of the minimum uncertainty in estimating parameters of the system Hamiltonian. The quantum…

Quantum Physics · Physics 2024-05-27 Aparajita Bhattacharyya , Ahana Ghoshal , Ujjwal Sen

In bosonic quantum metrology, the estimate of a loss parameter is typically performed by means of pure states, such as coherent, squeezed or entangled states, while mixed thermal probes are discarded for their inferior performance. Here we…

Quantum Physics · Physics 2018-10-17 Gaetana Spedalieri , Cosmo Lupo , Samuel L. Braunstein , Stefano Pirandola

Characterizing and understanding the environment affecting quantum systems is critical to elucidate its physical properties and engineer better quantum devices. We develop an approach to reduce the quantum environment causing single-qubit…

Quantum Physics · Physics 2022-10-19 Won Kyu Calvin Sun , Paola Cappellaro

Using a single quantum probe to sense other quantum objects offers distinct advantages but suffers from some limitations that may degrade the sensing precision severely, especially when the probe-target coupling is weak. Here we propose a…

Quantum Physics · Physics 2018-07-10 Yi-Nan Fang , Xing Xiao , Chang-Pu Sun , Wen Yang , Nan Zhao

Simultaneous quantum estimation of multiple parameters has recently become essential in quantum metrology. Although the ultimate sensitivity of a multiparameter quantum estimation in noiseless environments can beat the standard quantum…

Quantum Physics · Physics 2020-08-12 Le Bin Ho , Hideaki Hakoshima , Yuichiro Matsuzaki , Masayuki Matsuzaki , Yasushi Kondo

Gaussian quantum probes have been widely used in quantum metrology and thermometry, where the goal is to estimate the temperature of an environment with which the probe interacts. It was recently shown that introducing initial…

We consider how to characterize the dynamics of a quantum system from a restricted set of initial states and measurements using Bayesian analysis. Previous work has shown that Hamiltonian systems can be well estimated from analysis of noisy…

Quantum Physics · Physics 2014-03-04 S. G. Schirmer , D. K. L. Oi

A classical thermometer typically works by exchanging energy with the system being measured until it comes to equilibrium, at which point the readout is related to the final energy state of the thermometer. A recent paper noted that…

Quantum Physics · Physics 2016-09-07 W. K. Tham , H. Ferretti , A. V. Sadashivan , A. M. Steinberg