Research Highlights

Our recent studies concern the dynamics of particles in ring-shaped geometries. In particular we consider circuits: (a) with classical particles that perform stochastic motion; (b) with quantum Bose particles whose dynamics is coherent.
 
(a) It is possible to induce non-equilibrium steady state current, which requires e.g. a radiation source. We have studied the non-monotonic dependence of the current on the intensity of the driving, and its statistical properties. We also have addressed questions that concern the relaxation of such current, and how it depends on percolation and localization properties of the model. (b) Superfluidity is the possibility to have a current that does not decay even in the absence of an external driving source. Our study provides a theory for the meta-stability of such flow-states. A central observation is that the analysis should take into account the chaos that prevails in the classical limit of the model. It is the first time that the theory of "chaos" meets the theory of super-fluidity.
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Non-equilibrium steady state of stochastic circuits
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Dynamics of condensed particles in a few site system
 
A major theme in our studies during 2011-2015 was a "resistor network" theory for the energy absorption of weakly chaotic systems. Applications: the heating of cold atoms in vibrating traps; the conductance of closed mesoscopic rings.

The scope of the 2003-2006 publications was to place quantum pumping in open systems and quantum stirring in closed systems under the same umbrella of linear response theory (Kubo). The focus was on "ring" geometry (either "two barrier" or "piston" systems). In 2008 there are new works that illuminate the physical results using a heuristic "splitting ratio" approach. This direction has matured at 2013. The simplest model to clarify the idea is a 3-site tight-binding system. Additionally this "splitting ratio" approach has been used to derive some results for the counting statistics. Another direction was to apply the formalism to Bose condensed particles, and to see what is the significance of having interactions.
 
The links below contain descriptions of some older highlights. They are grouped by topic.
  • Non-equilibrium steady state of "sparse" systems (2011) [HTML]
  • Energy absorption by "glassy" systems (2011) [HTML]
  • The mesoscopic conductance of closed rings (2006-2008) [HTML]
  • Semi linear response theory (2005-2006) [HTML]
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  • References: Quantum pumping and stirring [HTML]
  • Report: Quantum stirring and counting statistics (2008) [HTML]
  • Counting statistics in closed and multiple path geometries (2007-2008) [HTML]
  • Quantum stirring of particles in closed devices (2005-2008) [HTML]
  • Operating a quantum pump in a closed circuit (2002-2006) [HTML]
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  • Non-perturbative response of driven mesoscopic systems (1998-2002) [HTML]
  • Report: The quest for quantum anomalies in the theory of response (2010) [HTML]
  • Rate of energy absorption for a driven chaotic cavity (2000) [HTML]
  • Report: Energy Absorption by driven mesoscopic Systems [arXiv] (2000)
  • Driven systems (1996-2000) [HTML]
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  • Dynamics of condensed particles in a few site system (2011) [HTML]
  • Wavepacket dynamics and quantum reversibility (1999-2005) [HTML]
  • Diffractive energy spreading and its semiclassical limit (2006) [HTML]
  • Parametric evolution of wavefunctions (2000-2006) [HTML]
  • Report: Detailed versus restricted quantum-classical correspondence (2006) [HTML]
  • Report: Regimes in the theory of wavepacket dynamics (2000) [HTML]
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  • Quantum dissipation in extended environment (2009) [Wiki]
  • The dephasing rate SP formula (2009) [Wiki]
  • The dephasing rate formula (1997-1999, 2007-2008) [HTML]
  • Report: Brownian Motion and Dephasing due to Dynamical Disorder (2000) [arXiv]
  • Quantum dissipation due to the interaction with chaos (2001-2004) [HTML]
  • Quantal Brownian Motion - Dephasing and Dissipation (1998-1999) [HTML]
  • The kicked rotator - localization, noise, dissipation (1987-1993) [Wiki]
  • Report: The effect of noise and dissipation on quantum chaos (1987-1993) [HTML]
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  • The semiclassical quantal-classical duality (1997-1998) [HTML]
  • The information entropy of quantum mechanical states (2004) [HTML]
  • Microelectronics and infrared physics (1992-1996) [HTML]