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Significant efforts are being spent on building a quantum computer. At the same time, developments in quantum software are rapidly progressing. Insufficient quantum resources often are the problem when running quantum algorithms. New…

Quantum Physics · Physics 2025-10-06 Niels M. P. Neumann , Carlos M. R. Rocha , Jasper Verbree , Marc van Vliet

A unified linear tearing-mode formulation is given incorporating both resistivity and Hall effects. A variational method is used that appears to be best suited to deal with the difficulties peculiar to the {\it triple-deck} structure…

Plasma Physics · Physics 2009-11-13 Bhimsen K. Shivamoggi

We consider the problem of constructing quantum operations or channels, if they exist, that transform a given set of quantum states $\{\rho_1, \dots, \rho_k\}$ to another such set $\{\hat\rho_1, \dots, \hat\rho_k\}$. In other words, we must…

Numerical Analysis · Mathematics 2014-07-25 Yuen-Lam Cheung , Dmitriy Drusvyatskiy , Chi-Kwong Li , Diane Pelejo , Henry Wolkowicz

Tunneling half lives are obtained in a minimalistic deformation picture of nuclear decays. As widely documented in other deformation models, one finds that the effective mass of the nucleus changes with the deformation parameter. However,…

Nuclear Theory · Physics 2024-08-28 Samyak Jain , A. Bhagwat

We consider three different approaches to analyze the quantum mechanical problems in multi-well potentials: i) the standard matrix diagonalization technique in the basis sets of harmonic oscillator eigenfunctions or plain waves; ii) the…

Quantum Physics · Physics 2020-12-11 V. P. Berezovoj , Yu. L. Bolotin , V. A. Cherkaskiy , M. I. Konchantnyi

The trace of a matrix function f(A), most notably of the matrix inverse, can be estimated stochastically using samples< x,f(A)x> if the components of the random vectors x obey an appropriate probability distribution. However such a…

Numerical Analysis · Mathematics 2021-08-26 Andreas Frommer , Mostafa Nasr Khalil , Gustavo Ramirez-Hidalgo

Back reaction of the particle creation on the quantum tunneling process is analyzed in real time formalism. We use quantum potential method in which whole quantum dynamics is exactly projected to a classical Hamilton-Jacobi equation with…

Quantum Physics · Physics 2007-05-23 Fumiaki Shibata , Masahiro Morikawa , Tetsuya Shiromizu , Masahide Yamaguchi

The assisted tunneling of a wave packet between square one dimensional barriers is treated analytically. The tunneling rate is calculated exactly for a potential mimicking a constant electric field with arbitrary time dependence. The pole…

Quantum Physics · Physics 2015-05-13 G. Kalbermann

Transfer matrix method is a well-known and extensively used tool to compute the reflection and transmission coefficients of electromagnetic waves when interacting with a system of layers parallel to each other. We present here a modified…

Optics · Physics 2017-03-14 Srinivas Ganganagunta

The inverse scattering method within the $J$-matrix approach to the two coupled-channel problem is discussed. We propose a generalization of the procedure to the case with different thresholds.

Quantum Physics · Physics 2009-11-13 S. A. Zaytsev

Recently, several groups have investigated quantum analogues of random walk algorithms, both on a line and on a circle. It has been found that the quantum versions have markedly different features to the classical versions. Namely, the…

Quantum Physics · Physics 2009-11-07 B. C. Travaglione , G. J. Milburn

We propose a unified framework that employs variational inference (VI) with (conditional) normalizing flows (NFs) to train both between-model and within-model proposals for reversible jump Markov chain Monte Carlo, enabling efficient…

Machine Learning · Statistics 2026-02-05 Pingping Yin , Xiyun Jiao

A multi-channel quantum router with four nodal cavities is constructed by two coupled-resonator waveguides and four single cavities. We can achieve directional routing by adjusting the probability of photon exiting from the specified port…

Quantum Physics · Physics 2023-06-21 Xu Yang , Lei Tan , Wu-Ming Liu

We propose a vector auto-regressive (VAR) model with a low-rank constraint on the transition matrix. This new model is well suited to predict high-dimensional series that are highly correlated, or that are driven by a small number of hidden…

Statistics Theory · Mathematics 2022-01-17 Pierre Alquier , Karine Bertin , Paul Doukhan , Rémy Garnier

In the fields of quantum mechanics and quantum information science, the traces of reduced density matrix powers play a crucial role in the study of quantum systems and have numerous important applications. In this paper, we propose a…

Quantum Physics · Physics 2025-07-24 Rui-Qi Zhang , Xiao-Qi Liu , Jing Wang , Ming Li , Shu-Qian Shen , Shao-Ming Fei

We generalize the string method, originally designed for the study of thermally activated rare events, to the calculation of quantum tunneling rates. This generalization is based on the analogy between quantum mechanics and statistical…

Statistical Mechanics · Physics 2007-05-23 Tiezheng Qian , Weiqing Ren , Jing Shi , Weinan E , Ping Sheng

We show that reflection symmetry has a strong influence on quantum transport properties. Using a random S-matrix theory approach, we derive the weak-localization correction, the magnitude of the conductance fluctuations, and the…

Condensed Matter · Physics 2009-10-28 Harold U. Baranger , Pier A. Mello

We investigate the scattering of two distinguishable particles with unequal masses and a mutual short-range interaction with the aim of quantifying the impact of a tunneling ``projectile'' particle on the quantum mechanical state of the…

Quantum Physics · Physics 2026-03-23 Roman Michelko , Peter Bokes

We introduce a novel hybrid algorithm to simulate the real-time evolution of quantum systems using parameterized quantum circuits. The method, named "projected - Variational Quantum Dynamics" (p-VQD) realizes an iterative, global projection…

Quantum Physics · Physics 2021-07-28 Stefano Barison , Filippo Vicentini , Giuseppe Carleo

We introduce a variational manifold of simple tensor network states for the study of a family of constrained models that describe spin-1/2 systems as realized by Rydberg atom arrays. Our manifold permits analytical calculation via…

Quantum Physics · Physics 2024-05-13 Joey Li , Giuliano Giudici , Hannes Pichler