scholarly journals Pair-excitation energetics of highly correlated many-body states

2013 ◽  
Vol 15 (9) ◽  
pp. 093040 ◽  
Author(s):  
M Mootz ◽  
M Kira ◽  
S W Koch
Quantum ◽  
2020 ◽  
Vol 4 ◽  
pp. 231
Author(s):  
Paul Boes ◽  
Rodrigo Gallego ◽  
Nelly H. Y. Ng ◽  
Jens Eisert ◽  
Henrik Wilming

Fluctuation theorems impose constraints on possible work extraction probabilities in thermodynamical processes. These constraints are stronger than the usual second law, which is concerned only with average values. Here, we show that such constraints, expressed in the form of the Jarzysnki equality, can be by-passed if one allows for the use of catalysts---additional degrees of freedom that may become correlated with the system from which work is extracted, but whose reduced state remains unchanged so that they can be re-used. This violation can be achieved both for small systems but also for macroscopic many-body systems, and leads to positive work extraction per particle with finite probability from macroscopic states in equilibrium. In addition to studying such violations for a single system, we also discuss the scenario in which many parties use the same catalyst to induce local transitions. We show that there exist catalytic processes that lead to highly correlated work distributions, expected to have implications for stochastic and quantum thermodynamics.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Grigory E. Astrakharchik ◽  
Luis A. Peña Ardila ◽  
Richard Schmidt ◽  
Krzysztof Jachymski ◽  
Antonio Negretti

AbstractThe presence of strong interactions in a many-body quantum system can lead to a variety of exotic effects. Here we show that even in a comparatively simple setup consisting of a charged impurity in a weakly interacting bosonic medium the competition of length scales gives rise to a highly correlated mesoscopic state. Using quantum Monte Carlo simulations, we unravel its vastly different polaronic properties compared to neutral quantum impurities. Moreover, we identify a transition between the regime amenable to conventional perturbative treatment in the limit of weak atom-ion interactions and a many-body bound state with vanishing quasi-particle residue composed of hundreds of atoms. In order to analyze the structure of the corresponding states, we examine the atom-ion and atom-atom correlation functions which both show nontrivial properties. Our findings are directly relevant to experiments using hybrid atom-ion setups that have recently attained the ultracold regime.


MRS Bulletin ◽  
1993 ◽  
Vol 18 (8) ◽  
pp. 23-28
Author(s):  
Z. Fisk ◽  
J.R. Schrieffer

The study of materials which have electronic phase transitions is a very active area. Such phase transitions include charge and spin density formation, as well the superconducting condensation in a rapidly expanding variety of materials. It is now common to lump these phenomena under the heading of correlated electron physics, involving as they do the essential role of electron-electron interactions in their occurrence. There are also materials in which there is found no electronic phase transition, but whose properties indicate strong electron-electron effects, such as a number of the so-called heavy fermion compounds. The part of condensed matter theory which addresses the particular physics of such materials is generally known as many-body physics. How to effectively treat strong electronic interactions theoretically is very much an unsolved problem, and theory does not give much more than limited guidance to the experimental research in this area. External magnetic fields have proved to be effective experimental probes of the properties of such systems, and the advent of increasingly strong pulsed fields is opening new possibilities for exposing and pulling apart the underlying electronic ground state of many such materials.


1998 ◽  
Vol 94 (3) ◽  
pp. 417-433 ◽  
Author(s):  
MARTIN VAN DER HOEF ◽  
PAUL MADDEN

2001 ◽  
Vol 60 (2) ◽  
pp. 99-107 ◽  
Author(s):  
Holger Schmid

Cannabis use does not show homogeneous patterns in a country. In particular, urbanization appears to influence prevalence rates, with higher rates in urban areas. A hierarchical linear model (HLM) was employed to analyze these structural influences on individuals in Switzerland. Data for this analysis were taken from the Switzerland survey of Health Behavior in School-Aged Children (HBSC) Study, the most recent survey to assess drug use in a nationally representative sample of 3473 15-year-olds. A total of 1487 male and 1620 female students indicated their cannabis use and their attributions of drug use to friends. As second level variables we included address density in the 26 Swiss Cantons as an indicator of urbanization and officially recorded offences of cannabis use in the Cantons as an indicator of repressive policy. Attribution of drug use to friends is highly correlated with cannabis use. The correlation is even more pronounced in urban Cantons. However, no association between recorded offences and cannabis use was found. The results suggest that structural variables influence individuals. Living in an urban area effects the attribution of drug use to friends. On the other hand repressive policy does not affect individual use.


2013 ◽  
Vol 72 (1) ◽  
pp. 5-11 ◽  
Author(s):  
Elise S. Dan-Glauser ◽  
Klaus R. Scherer

Successful emotion regulation is a key aspect of efficient social functioning and personal well-being. Difficulties in emotion regulation lead to relationship impairments and are presumed to be involved in the onset and maintenance of some psychopathological disorders as well as inappropriate behaviors. Gratz and Roemer (2004 ) developed the Difficulties in Emotion Regulation Scale (DERS), a comprehensive instrument measuring emotion regulation problems that encompasses several dimensions on which difficulties can occur. The aim of the present work was to develop a French translation of this scale and to provide an initial validation of this instrument. The French version was created using translation and backtranslation procedures and was tested on 455 healthy students. Congruence between the original and the translated scales was .98 (Tucker’s phi) and internal consistency of the translation reached .92 (Cronbach’s α). Moreover, test-retest scores were highly correlated. Altogether, the initial validation of the French version of the DERS (DERS-F) offers satisfactory results and permits the use of this instrument to map difficulties in emotion regulation in both clinical and research contexts.


1968 ◽  
Vol 111 (1) ◽  
pp. 392-416 ◽  
Author(s):  
K DIETRICH ◽  
K HARA

1970 ◽  
Vol 31 (C4) ◽  
pp. C4-99-C4-104
Author(s):  
T. P. DAS ◽  
C. M. DUTTA ◽  
N. C. DUTTA

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