10,474 research outputs found
Non equilibrium phase transitions and Floquet Kibble-Zurek scaling
We study the slow crossing of non-equilibrium quantum phase transitions in
periodically-driven systems. We explicitly consider a spin chain with a uniform
time-dependent magnetic field and focus on the Floquet state that is
adiabatically connected to the ground state of the static model. We find that
this {\it Floquet ground state} undergoes a series of quantum phase transitions
characterized by a non-trivial topology. To dinamically probe these
transitions, we propose to start with a large driving frequency and slowly
decrease it as a function of time. Combining analytical and numerical methods,
we uncover a Kibble-Zurek scaling that persists in the presence of moderate
interactions. This scaling can be used to experimentally demonstrate
non-equilibrium transitions that cannot be otherwise observed.Comment: 7 pages, 3 figures, Supplemental Material. (In this last version, the
one published in EPL, we provide a better discussion of the Floquet adiabatic
theorem, the construction of the Floquet ground state as an adiabatic
continuation and the nature of the phase transitions.
The role of auxiliary states in state discrimination with linear optical evices
The role of auxiliary photons in the problem of identifying a state secretly
chosen from a given set of L-photon states is analyzed. It is shown that
auxiliary photons do not increase the ability to discriminate such states by
means of a global measurement using only optical linear elements, conditional
transformation and auxiliary photons.Comment: 5 pages. 1 figure. RevTex documen
Geometric phase induced by a cyclically evolving squeezed vacuum reservoir
We propose a new way to generate an observable geometric phase by means of a
completely incoherent phenomenon. We show how to imprint a geometric phase to a
system by "adiabatically" manipulating the environment with which it interacts.
As a specific scheme we analyse a multilevel atom interacting with a broad-band
squeezed vacuum bosonic bath. As the squeezing parameters are smoothly changed
in time along a closed loop, the ground state of the system acquires a
geometric phase. We propose also a scheme to measure such geometric phase by
means of a suitable polarization detection.Comment: 4 pages, 1 figur
Stein & Hay: Cases and Materials on the Law and Institutions of the Atlantic Area
A Review of Cases and Materials on the Law and Institutions of the Atlantic Area Edited by Eric Stein and Peter Hay
Contemporary perspective on addictive behaviors: underpinning mechanisms, assessment, and treatment
This special issue gathered contributions from authors in the scientifc community working on addictive behaviors. In particular, authors were solicited to relate about underpinning mechanisms, assessment protocols, and intervention programs that are currently proposed for substance abuse,
Internet addiction, and other forms of problematic conducts in pediatric populations, adolescence, and adulthood. Most of the papers used a biopsychosocial model for the onset and maintaining of addictive behaviors and their comorbidities with other psychopathologies. Although the intent was accept
contributions focused on all forms of addictive behaviors, this special issue is composed of four papers concerning problematic use of the web and two articles focusing on substance use. Of note, all papers addressed the developmental phases of childhood and adolescence
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