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Nuclear Magnetic Resonance (NMR) forms a natural test-bed to perform quantum information processing (QIP) and has so far proven to be one of the most successful quantum information processors. The nuclear spins in a molecule treated as…

Quantum Physics · Physics 2012-10-30 Soumya Singha Roy

Driving a quantum system periodically in time can profoundly alter its long-time dynamics and trigger topological order. Such schemes are particularly promising for generating non-trivial energy bands and gauge structures in quantum-matter…

Quantum Gases · Physics 2015-06-11 N. Goldman , J. Dalibard

The semi-classical limit of quantum spin systems corresponds to a dynamical Lagrangian which contains the usual kinetic energy, the couplings and interactions of the spins and an additional, first order kinematical term which corresponds to…

High Energy Physics - Theory · Physics 2013-05-29 Avinash Khare , M. B. Paranjape

Tunneling is an iconic concept that captures the peculiarity of quantum dynamics but, despite its ubiquity, questions remain. We focus on strong-field tunneling, which is vital to all attosecond science. We find an unexpected optical…

Quantum Physics · Physics 2025-04-22 Anne Weber , Margarita Khokhlova , Emilio Pisanty

In this paper, we attempt the theoretical modeling of the magnetic tunnel junctions with embedded magnetic and nonmagnetic nanoparticles (NPs). A few abnormal tunnel magnetoresistance (TMR) effects, observed in related experiments, can be…

Mesoscale and Nanoscale Physics · Physics 2018-07-04 Arthur Useinov , Niazbeck Useinov , Lin-Xiu Ye , Te-Ho Wu , Chih-Huang Lai

In the second part of this paper in micro canonical ensemble the new numerical approach for consideration of quantum dynamics and calculations of the average values of quantum operators and time correlation functions in the Wigner…

Quantum Physics · Physics 2009-10-31 V. Filinov , Yu. Lozovik , A. Filinov , I. Zacharov , A. Oparin

Using an NMR quantum computer, we experimentally simulate the quantum phase transition of a Heisenberg spin chain. The Hamiltonian is generated by a multiple pulse sequence, the nuclear spin system is prepared in its (pseudo-pure) ground…

Quantum Physics · Physics 2009-11-10 Xinhua Peng , Jiangfeng Du , Dieter Suter

We study the dynamics of the classical and quantum mechanical scattering of a wave packet from an oscillating barrier. Our main focus is on the dependence of the transmission coefficient on the initial energy of the wave packet for a wide…

Chaotic Dynamics · Physics 2015-05-20 P. K. Papachristou , E. Katifori , F. K. Diakonos , V. Constantoudis , E. Mavrommatis

The dynamics of hybrid systems -- i.e. ones in which classical and quantum degrees of freedom co-exist and interact -- feature both diffusion in the classical sector and decoherence in the quantum state. In this article, we will consider…

Quantum Physics · Physics 2025-10-10 Emanuele Panella

A scanning tunneling microscope can probe the inelastic spin excitations of a single magnetic atom in a surface via spin-flip assisted tunneling in which transport electrons exchange spin and energy with the atomic spin. If the inelastic…

Mesoscale and Nanoscale Physics · Physics 2015-05-19 F. Delgado , J. Fernández-Rossier

The field of quantum simulation, which aims at using a tunable quantum system to simulate another, has been developing fast in the past years as an alternative to the all-purpose quantum computer. In particular, the use of temporal driving…

We theoretically investigate magnetoresistance (MR) effects in connection with spin filtering in quantum-coherent transport through tunnel junctions based on non-magnetic/semimagnetic heterostructures. We find that spin filtering in…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 J. C. Egues , C. Gould , G. Richter , L. W. Molenkamp

Experiments violating Bell's inequality appear to indicate deterministic models do not correspond to a realistic theory of quantum mechanics. The theory of pilot waves seemingly overcomes this hurdle via nonlocality and statistical…

Quantum Physics · Physics 2024-05-03 Aminur Rahman

We use an effective Hamiltonian to characterize particle dynamics and find escape rates in a periodically kicked Hamiltonian. We study a model of particles in storage rings that is described by a chaotic symplectic map. Ignoring the…

Statistical Mechanics · Physics 2017-07-31 Archishman Raju , Sayan Choudhury , David L. Rubin , Amie Wilkinson , James P. Sethna

Preserving quantum coherence with the increase of a system's size and complexity is a major challenge. Molecules, with their diverse sizes and complexities and many degrees of freedom, are an excellent platform for studying the transition…

Quantum Physics · Physics 2024-09-23 Tamar Levin , Ziv Meir

Motivated by recent realizations of qubits with a readout by macroscopic quantum tunneling in a Josephson junction, we study the problem of barrier penetration in presence of coupling to a spin-${1\over 2}$ system. It is shown that when the…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Joachim Ankerhold , Hermann Grabert

Quantum tunneling was observed in the decay of metastable spin domains in gaseous Bose-Einstein condensates. A mean-field description of the tunneling was developed and compared with measurement. The tunneling rates are a sensitive probe of…

Condensed Matter · Physics 2009-10-31 D. M. Stamper-Kurn , H. -J. Miesner , A. P. Chikkatur , S. Inouye , J. Stenger , W. Ketterle

Fifty years of developments in nuclear magnetic resonance (NMR) have resulted in an unrivaled degree of control of the dynamics of coupled two-level quantum systems. This coherent control of nuclear spin dynamics has recently been taken to…

Quantum Physics · Physics 2015-06-26 Lieven M. K. Vandersypen , Isaac L. Chuang

We study within the spin-boson dynamics the synchronization of quantum tunneling with an external periodic driving signal. As a main result we find that at a sufficiently large system-bath coupling strength (Kondo parameter a>1) the thermal…

Statistical Mechanics · Physics 2007-06-13 Igor Goychuk , Jesus Casado-Pascual , Manuel Morillo , Joerg Lehmann , Peter Hanggi

The nonintegrable Hamiltonian dynamics of particles placed in a symmetric, spatially periodic potential and subjected to a periodically varying field is explored. Such systems can exhibit a rich diversity of unusual transport features. In…

Chaotic Dynamics · Physics 2008-07-10 D. Hennig , L. Schimansky-Geier , P. Hänggi
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