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Related papers: Quantum tunneling on graphs

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We present the mathematical model and numerical calculation results for the tunneling of the wave function in a time-periodic double-well potential. The bi-quadratic potential of a double-well form is used. Based on a mathematical model of…

Quantum Physics · Physics 2025-07-09 Vladimir Dubinko , Oleksandr Mazmanishvili

This is an analysis of some aspects of an old but still controversial topic, superluminal quantum tunneling. Some features of quantum tunneling described in literature, such as definition of the tunneling time and a frequency range of a…

Quantum Physics · Physics 2020-09-15 Moses Fayngold

We examine quantum transport in periodic quantum graphs with a vertex coupling non-invariant with respect to time reversal. It is shown that the graph topology may play a decisive role in the conductivity properties illustrating this claim…

Mathematical Physics · Physics 2020-05-20 Pavel Exner , Jiri Lipovsky

Quantum theory has shown its superiority in enhancing machine learning. However, facilitating quantum theory to enhance graph learning is in its infancy. This survey investigates the current advances in quantum graph learning (QGL) from…

Machine Learning · Computer Science 2023-02-03 Shuo Yu , Ciyuan Peng , Yingbo Wang , Ahsan Shehzad , Feng Xia , Edwin R. Hancock

We discuss a particular kind of quantum walk on a general graph. We affix two semi-infinite lines to a general finite graph, which we call tails. On the tails, the particle making the walk simply advances one unit at each time step, so that…

Quantum Physics · Physics 2009-07-15 Edgar Feldman , Mark Hillery

Optimizing the probability of quantum tunneling between two states, while keeping the resources of the underlying physical system constant, is a task of key importance due to its critical role in various applications. We show that, by…

A new quantum approach is presented that can account for the description of small ferromagnetic particles magnetization tunneling. An estimate of the saturation value of an external applied magnetic field along the easy axis is obtained. An…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 D. Galetti , B. M. Pimentel , C. L. Lima , E. C. Silva

Despite quantum tunneling has been studied since the advent of quantum mechanics, the literature appears to contain no simple (textbook) formula for tunneling in generic asymmetric double-well potentials. In the regime of strong…

Quantum Physics · Physics 2012-07-19 Gianluca Rastelli

The meaning of `tunneling' in a timeless theory such as quantum cosmology is discussed. A recent suggestion of `tunneling' of the macroscopic universe at the classical turning point is analyzed in an anisotropic and inhomogeneous toy model.…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Heinz-Dieter Conradi

We study how quantum walks can be used to find structural anomalies in graphs via several examples. Two of our examples are based on star graphs, graphs with a single central vertex to which the other vertices, which we call external…

Quantum Physics · Physics 2015-06-05 Mark Hillery , Hongjun Zheng , Edgar Feldman , Daniel Reitzner , Vladimir Buzek

We investigate the flat phase of quantum polymerized phantom membranes by means of a nonperturbative renormalization group approach. We first implement this formalism for general quantum polymerized membranes and derive the flow equations…

Statistical Mechanics · Physics 2016-09-30 O. Coquand , D. Mouhanna

Theoretical research into many-body quantum systems has mostly focused on regular structures which have a small, simple unit cell and where a vanishingly small number of pairs of the constituents directly interact. Motivated by advances in…

Quantum Physics · Physics 2022-12-06 Joseph Tindall , Amy Searle , Abdulla Alhajri , Dieter Jaksch

Solutions to explicit time-dependent problems in quantum mechanics are rare. In fact, all known solutions are coupled to specific properties of the Hamiltonian and may be divided into two categories: One class consists of time-dependent…

Quantum Physics · Physics 2007-05-23 Tobias Kramer , Marcos Moshinsky

We study the effect of electron tunneling on the level statistics of quantum dots. While the coupling between individual levels and the electron reservoir leads predominantly to the expected level broadening, the indirect coupling of…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Jürgen König , Yuval Gefen , Gerd Schön

Quantum tunneling is a valuable resource exploited by quantum annealers to solve complex optimization problems. Tunneling events also occur during projective quantum Monte Carlo (PQMC) simulations, and in a class of problems characterized…

Quantum Physics · Physics 2019-12-16 T. Parolini , E. M. Inack , G. Giudici , S. Pilati

Following our work [Phys. Rev. Lett. 125, 020401 (2020)], we discuss a semiclassical description of one-dimensional quantum tunneling through multibarrier potentials in terms of complex time. We start by defining a complex-extended…

Quantum Physics · Physics 2021-06-09 Pavel Stránský , Milan Šindelka , Pavel Cejnar

We study the conductance spectrum of graphene quantum dots, both single and multiple cases. The single electron tunneling phenomenon is investigated and the periodicity, amplitude and line shape of the Coulomb blockade oscillations at low…

Mesoscale and Nanoscale Physics · Physics 2009-11-17 Qiong Ma , Tao Tu , Zhi-Rong Lin , Guang-Can Guo , Guo-Ping Guo

We report tunneling phenomena in double In$_{0.53}$Ga$_{0.47}$As quantum-well structures that are at odds with the conventional parallel-momentum-conserving picture of tunneling between two-dimensional systems. We found that the tunneling…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Y. Lin , J. Nitta , ; A. K. M. Newaz , W. Song , E. E. Mendez

We examine transmission through a quantum graph vertex to which auxiliary edges with constant potentials are attached. We find a characterization of vertex couplings for which the transmission probability from a given "input" line to a…

Mathematical Physics · Physics 2016-01-01 Ondřej Turek

We introduce a model of a quantum walk on a graph in which a particle jumps between neighboring nodes and interacts with independent spins sitting on the edges. Entanglement propagates with the walker. We apply this model to the case of a…

Quantum Physics · Physics 2021-03-30 Kevissen Sellapillay , Alberto D. Verga