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Related papers: Comment on the Adiabatic Condition

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We show that the difference of adiabatic phases, that are basis-dependent, in noncyclic evolution of non-degenerate quantum systems have to be taken into account to give the correct interference result in the calculation of physical…

Quantum Physics · Physics 2009-08-07 M. T. Thomaz , A. C. Aguiar Pinto , M. Moutinho

In this paper we define a non-dynamical phase for a spin-1/2 particle in a rotating magnetic field in the non-adiabatic non-cyclic case, and this phase can be considered as a generalized Berry phase. We show that this phase reduces to the…

Quantum Physics · Physics 2012-12-11 Siamak S. Gousheh , Azadeh Mohammadi , Leila Shahkarami

We derive the general formula giving the Berry phase for an arbitrary spin, having both magnetic-dipole and electric-quadrupole couplings with external time-dependent fields. We assume that the effective E and B fields remain orthogonal…

Quantum Physics · Physics 2015-05-19 Marie-Anne Bouchiat , Claude Bouchiat

The geometric phase has been proposed as a candidate for noise resilient coherent manipulation of fragile quantum systems. Since it is determined only by the path of the quantum state, the presence of noise fluctuations affects the…

Quantum Physics · Physics 2010-04-22 S. Filipp , J. Klepp , Y. Hasegawa , C. Plonka-Spehr , U. Schmidt , P. Geltenbort , H. Rauch

We calculate Berry's phase when the driving field, to which a spin-1/2 is coupled adiabatically, rather than the familiar classical magnetic field, is a quantum vector operator, of noncommuting, in general, components, e.g., the angular…

Quantum Physics · Physics 2016-09-14 Pedro Aguilar , Chryssomalis Chryssomalakos , Edgar Guzman

The effect of fluctuations in the classical control parameters on the Berry phase of a spin 1/2 interacting with a adiabatically cyclically varying magnetic field is analyzed. It is explicitly shown that in the adiabatic limit dephasing is…

Quantum Physics · Physics 2009-11-10 Gabriele De Chiara , G. Massimo Palma

The monopole-like singularity of Berry's adiabatic phase in momentum space and associated anomalous Poisson brackets have been recently discussed in various fields. With the help of the results of an exactly solvable version of Berry's…

High Energy Physics - Theory · Physics 2020-04-22 Shinichi Deguchi , Kazuo Fujikawa

The adiabatic theorem states that if we prepare a quantum system in one of the instantaneous eigenstates then the quantum number is an adiabatic invariant and the state at a later time is equivalent to the instantaneous eigenstate at that…

Quantum Physics · Physics 2007-05-23 A. K. Pati , A. K. Rajagopal

Geometric phases in quantum mechanics play an extraordinary role in broadening our understanding of fundamental significance of geometry in nature. One of the best known examples is the Berry phase (M.V. Berry (1984), Proc. Royal. Soc.…

Statistical Mechanics · Physics 2012-05-11 V. Gritsev , A. Polkovnikov

Berry's phase often appears in quantum two-level systems with a degeneracy. An example of such a system is a spin-1/2 particle in a magnetic field. As the magnetic field is slowly evolved through a closed path, the particle has been shown…

Other Condensed Matter · Physics 2009-09-15 Anthony Tyler , Roberto C. Ramos

The physical reality and observability of 2n\pi Berry phases, as opposed to the usually considered modulo 2\pi topological phases is demonstrated with the help of computer simulation of a model adiabatic evolution whose parameters are…

Quantum Physics · Physics 2009-11-07 Rajendra Bhandari

We consider a two-level system coupled to an environment that evolves non-adiabatically. We present a non-perturbative method for determining the persistence amplitude whose phase contains all the corrections to Berry's phase produced by…

Quantum Physics · Physics 2007-05-23 Frank Gaitan

We show that Berry's geometrical (topological) phase for circular quantum dots with an odd number of electrons is equal to \pi and that eigenvalues of the orbital angular momentum run over half-integer values. The non-zero value of the…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 V. D. Mur , N. B. Narozhny , A. N. Petrosyan , Yu. E. Lozovik

We introduce the perturbative aspects of noncommutative quantum mechanics. Then we study the Berry's phase in the framework of noncommutative quantum mechanics. The results show deviations from the usual quantum mechanics which depend on…

High Energy Physics - Theory · Physics 2009-11-07 S. A. Alavi

An electron spin moving adiabatically in a strong, spatially non-uniform magnetic field accumulates a geometric phase or Berry phase, which might be observable as a conductance oscillation in a mesoscopic ring. Two contradicting theories…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 S. A. van Langen , H. P. A. Knops , J. C. J. Paasschens , C. W. J. Beenakker

We propose a new formula for the adiabatic Berry phase which is based on phase-space formulation of quantum mechanics. This approach sheds a new light into the correspondence between classical and quantum adiabatic phases -- both phases are…

Quantum Physics · Physics 2007-05-23 Dariusz Chruscinski

The geometric (Berry) phase of a two-level system in a dissipative environment is analyzed by using the second-quantized formulation, which provides a unified and gauge-invariant treatment of adiabatic and nonadiabatic phases and is thus…

Quantum Physics · Physics 2009-05-09 Kazuo Fujikawa , Ming-Guang Hu

The quantum superposition principle is reconsidered based on adiabatic theorem of quantum mechanics, nonadiabatic dressed states and experimental evidence. The physical mechanism and physical properties of the quantum superposition are…

General Physics · Physics 2023-11-07 Ivan Georgiev Koprinkov

In 1984 Michael Berry discovered that an isolated eigenstate of an adiabatically changing periodic Hamiltonian $H(t)$ acquires a phase, called the Berry phase. We show that under very general assumptions the adiabatic approximation of the…

Mathematical Physics · Physics 2015-06-17 Maxim Braverman

The usual, "static" version of the quantum Zeno effect consists in the hindrance of the evolution of a quantum systems due to repeated measurements. There is however a "dynamic" version of the same phenomenon, first discussed by von Neumann…

Quantum Physics · Physics 2007-05-23 P. Facchi , S. Pascazio
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