English
Related papers

Related papers: Scheme for accelerating quantum tunneling dynamics

200 papers

This work establishes a firm relationship between classical nonlinear resonances and the phenomenon of dynamical tunneling. It is shown that the classical phase space with its hierarchy of resonance islands completely characterizes…

Chaotic Dynamics · Physics 2007-07-31 Srihari Keshavamurthy

In the standard formulation of quantum mechanics, one starts by proposing a potential function that models the physical system. The potential is then inserted into the Schr\"odinger equation, which is solved for the wave function, bound…

Quantum Physics · Physics 2015-07-28 A. D. Alhaidari , M. E. H. Ismail

We investigate quantum tunneling in the theory of a complex scalar field with a global $U(1)$ symmetry when the charge density of the initial configuration does not vanish. We discuss the possible final configurations and set up the…

High Energy Physics - Phenomenology · Physics 2009-10-28 Kimyeong Lee

Quantum tunneling remains unexplored in many regimes of many-body quantum physics, including the effect of quantum phase transitions on tunneling dynamics. In general, the quantum phase is a statement about the ground state and has no…

Quantum Gases · Physics 2021-09-03 Diego A. Alcala , Marie A. McLain , Lincoln D. Carr

We propose and study ways speeding up of the entangling operations in the trapped ions system with high fidelity. First, we find a scheme to increase the speed of a two-qubit gate without the limitation of trap frequency, which was…

Quantum Physics · Physics 2023-03-31 Kaizhao Wang , Jing-Fan Yu , Pengfei Wang , Chunyang Luan , Jing-Ning Zhang , Kihwan Kim

The Bloch sphere representation is a geometric model for all possible quantum states of a two-level system that can be used to describe the time dynamics of a qubit. As explicit application, we consider the time dynamics of a particle in a…

Physics Education · Physics 2024-10-31 Jonas Bley , Vieri Mattei , Simon Goorney , Jacob Sherson , Stefan Heusler

We follow up the work, where in light of the Picard-Lefschetz thimble approach, we split up the real-time path integral into two parts: the initial density matrix part which can be represented via an ensemble of initial conditions, and the…

High Energy Physics - Theory · Physics 2020-01-29 Zong-Gang Mou , Paul M. Saffin , Anders Tranberg

We present a simple model for electron transport in semiconductor devices that exhibit tunneling between the conduction and valence bands. The model is derived within the usual Bloch-Wannier formalism by a k-expansion, and is formulated in…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Omar Morandi , Michele Modugno

We consider a minisuperspace model for a closed universe with small and positive cosmological constant, filled with a massive scalar field conformally coupled to gravity. In the quantum version of this model, the universe may undergo a…

General Relativity and Quantum Cosmology · Physics 2009-11-07 D. Levkov , C. Rebbi , V. A. Rubakov

Quasiclassical methods are used to define dynamical tunneling times in models of quantum cosmological bounces. These methods provide relevant new information compared with the traditional treatment of quantum tunneling by means of tunneling…

General Relativity and Quantum Cosmology · Physics 2021-11-18 Martin Bojowald , Brenda Jones

Classical algorithms are often not effective for solving nonconvex optimization problems where local minima are separated by high barriers. In this paper, we explore possible quantum speedups for nonconvex optimization by leveraging the…

Quantum Physics · Physics 2023-06-07 Yizhou Liu , Weijie J. Su , Tongyang Li

In this paper, we propose a quantum algorithm that combines the momentum accelerated gradient method with Schr\"odingerization [S. Jin, N. Liu and Y. Yu, Phys. Rev. Lett, 133 (2024), 230602][S. Jin, N. Liu and Y. Yu, Phys. Rev. A, 108…

Quantum Physics · Physics 2025-09-23 Qitong Hu , Xiaoyang He , Shi Jin , Xiao-Dong Zhang

We study the Schwinger effect, in which the external field having a spatiotemporal profile creates electron-positron pairs via multidimensional quantum tunneling. Our treatment is based on the trace formula for the QED effective action,…

High Energy Physics - Theory · Physics 2016-04-13 Cesim K. Dumlu

We investigate the time-dependent, coherent, and dissipative dynamics of bound particles in single multilevel quantum dots in the presence of sequential tunnelling transport. We focus on the nonequilibrium regime where several channels are…

Mesoscale and Nanoscale Physics · Physics 2010-02-11 Eduardo Vaz , Jordan Kyriakidis

The approximation of quantum unitary dynamics of a particle by a swarm of point wise classical samples of this particle is proposed. Quantum mechanism of speedup rests on the creation and annihilation of absolutely rigid bons, which join…

General Physics · Physics 2011-12-05 Yuri Ozhigov

The fast forward scheme of adiabatic quantum dynamics is applied to finite regular spin clusters with various geometries and the nature of driving interactions is elucidated. The fast forward is the quasi-adiabatic dynamics guaranteed by…

Quantum Physics · Physics 2019-06-26 Iwan Setiawan , Bobby Eka Gunara , Sanat Avazbaev , Katsuhiro Nakamura

Field-tuned quantum tunneling in two single-molecule magnets coupled antiferromagnetically and formed a supramolecule dimer is studied. We obtain step-like magnetization curves by means of the numerically exact solution of the…

Materials Science · Physics 2009-11-10 Yuanchang Su , Ruibao Tao

We study the tunneling of slow quantum packets through a high Coulomb barrier. We show that the transmission coefficient can be quite different from the standard expression obtained in the plane wave (WKB) approximation (and larger by many…

Quantum Physics · Physics 2015-06-18 A. V. Dodonov , V. V. Dodonov

Quantum tunneling, a phenomenon in which a quantum state traverses energy barriers above the energy of the state itself, has been hypothesized as an advantageous physical resource for optimization. Here we show that multiqubit tunneling…

A semi-classical model based on quantum time concepts is presented for the evaluation of bremsstrahlung emission probabilities in alpha decay of nuclei. The contribution to the bremsstrahlung emission from the different regions in tunneling…

Nuclear Theory · Physics 2014-01-10 N. G. Kelkar , M. Nowakowski