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Related papers: Identifying quantum change points for Hamiltonians

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Unwanted interaction between a quantum system and its fluctuating environment leads to decoherence and is the primary obstacle to establishing a scalable quantum information processing architecture. Strategies such as environmental and…

We examine the physical manifestations of exceptional points and passage times in a two-level system which is subjected to quantum measurements and which admits a non-Hermitian description. Using an effective Hamiltonian acting in the…

Quantum Physics · Physics 2015-06-12 A. Thilagam

An effective Hamiltonian describing interaction between generic "fast" and a "slow" systems is obtained in the strong interaction limit. The result is applied for studying the effect of quantum phase transition as a bifurcation of the…

Quantum Physics · Physics 2009-11-13 Isabel Sainz , Andrei B. Klimov , Luis Roa

The identification of time-varying \textit{in situ} signals is crucial for characterizing the dynamics of quantum processes occurring in highly isolated environments. Under certain circumstances, they can be identified from time-resolved…

Quantum Physics · Physics 2021-03-03 Xi Cao , Yu-xi Liu , Rebing Wu

Quantum shape-phase transitions in finite nuclei are considered in the framework of the interacting boson model. Critical-point Hamiltonians for first- and second-order transitions are identified by resolving them into intrinsic and…

Nuclear Theory · Physics 2008-11-26 A. Leviatan

We study the multivariate nonparametric change point detection problem, where the data are a sequence of independent $p$-dimensional random vectors whose distributions are piecewise-constant with Lipschitz densities changing at unknown…

Statistics Theory · Mathematics 2020-06-26 Oscar Hernan Madrid Padilla , Yi Yu , Daren Wang , Alessandro Rinaldo

We propose a Newton algorithm to characterize the Hamiltonian of a quantum system interacting with a given laser field. The algorithm is based on the assumption that the evolution operator of the system is perfectly known at a fixed time.…

Quantum Physics · Physics 2015-06-22 M. Ndong , J. Salomon , D. Sugny

In this note we address the exact solutions of a time-dependent Hamiltonian composed by an oscillator-like interaction with both a frequency and a mass term that depend on time. The latter is achieved by constructing the appropriate point…

Quantum Physics · Physics 2020-02-26 Kevin Zelaya , Véronique Hussin

In this article, we develop a numerical method to find optimal control pulses that accounts for the separation of timescales between the variation of the input control fields and the applied Hamiltonian. In traditional numerical…

Quantum Physics · Physics 2011-09-19 F. Motzoi , J. M. Gambetta , S. T. Merkel , F. K. Wilhelm

We consider the problem of selectively controlling couplings in a practical quantum processor with always-on interactions that are diagonal in the computational basis, using sequences of local NOT gates. This methodology is well-known in…

Quantum Physics · Physics 2020-09-11 Takahiro Tsunoda , Gaurav Bhole , Stephen A. Jones , Jonathan A. Jones , Peter J. Leek

We present a machine-learning method for predicting sharp transitions in a Hamiltonian phase diagram by extrapolating the properties of quantum systems. The method is based on Gaussian Process regression with a combination of kernels chosen…

Other Condensed Matter · Physics 2019-04-26 Rodrigo A. Vargas-Hernández , John Sous , Mona Berciu , Roman V. Krems

The control of quantum phenomena is a topic that has carried out many challenging problems. Among others, the Hamiltonian identification, i.e, the inverse problem associated with the unknown features of a quantum system is still an open…

Optimization and Control · Mathematics 2009-03-11 Yvon Maday , Julien Salomon

We show that the general Heisenberg Hamiltonian with non-uniform couplings can be characterised by mapping the entanglement it generates as a function of time. Identification of the Hamiltonian in this way is possible as the coefficients of…

Quantum Physics · Physics 2007-05-23 Jared H. Cole , Simon J. Devitt , Lloyd C. L. Hollenberg

Hamiltonian mechanics is an effective tool to represent many physical processes with concise yet well-generalized mathematical expressions. A well-modeled Hamiltonian makes it easy for researchers to analyze and forecast many related…

Machine Learning · Computer Science 2021-02-24 Seungjun Lee , Haesang Yang , Woojae Seong

Process monitoring and control requires detection of structural changes in a data stream in real time. This article introduces an efficient sequential Monte Carlo algorithm designed for learning unknown changepoints in continuous time. The…

Applications · Statistics 2015-09-29 Melissa J. M. Turcotte , Nicholas A. Heard

With many Hamiltonians one can naturally associate a |Psi|^2-distributed Markov process. For nonrelativistic quantum mechanics, this process is in fact deterministic, and is known as Bohmian mechanics. For the Hamiltonian of a quantum field…

Quantum Physics · Physics 2007-05-23 Detlef Duerr , Sheldon Goldstein , Roderich Tumulka , Nino Zanghi

Hamilton's equations of motion are local differential equations and boundary conditions are required to determine the solution uniquely. Depending on the choice of boundary conditions, a Hamiltonian may thereby describe several different…

Quantum Physics · Physics 2024-04-02 Carl M. Bender , Daniel W. Hook

We consider a qubit subject to various independent control mechanisms and present a general strategy to identify both the internal Hamiltonian and the interaction Hamiltonian for each control mechanism, relying only on a single, fixed…

Quantum Physics · Physics 2009-11-10 Sonia G. Schirmer , Daniel K. L. Oi , Avinash Kolli , Jared H. Cole

We address the problem of simulating pair-interaction Hamiltonians in n node quantum networks where the subsystems have arbitrary, possibly different, dimensions. We show that any pair-interaction can be used to simulate any other by…

Quantum Physics · Physics 2023-11-27 Pawel Wocjan , Martin Roetteler , Dominik Janzing , Thomas Beth

We present efficient quantum algorithms for simulating time-dependent Hamiltonian evolution of general input states using an oracular model of a quantum computer. Our algorithms use either constant or adaptively chosen time steps and are…

Quantum Physics · Physics 2011-11-03 Nathan Wiebe , Dominic W. Berry , Peter Hoyer , Barry C. Sanders