TODAY CMSP Seminar Wednesday 23 May at 11 am Stasi Seminar Edward GRANT

[CM Section]

Condensed Matter and Statistical Physics Seminar
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Wednesday 23 Mayat 11:00 a.m.

Luigi Stasi Seminar Room, first floor, ICTP Leonardo building
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Speaker: Edward GRANT (Dept. of Chemistry, UBC, Vancouver, Canada)

Title:Possible Manifestations of Quantum Disordered Dynamics
in the Arrested Relaxation of a Molecular Ultracold Plasma

Abstract:
Spontaneous avalanche to plasma splits the core of an ellipsoidal 
Rydberg gas
of nitric oxide. Ambipolar expansion first quenches the electron 
temperature of
this core plasma. Then, long-range, resonant charge transfer from 
ballistic ions to
frozen Rydberg molecules in the wings of the ellipsoid quenches the 
centre-of-mass
ion/Rydberg molecule velocity distribution. This sequence of steps gives 
rise to a
remarkable mechanics of self-assembly, in which the kinetic energy of 
initially formed
hot electrons and ions drives an observed separation of plasma volumes. 
These
dynamics adiabatically sequester energy in a reservoir of mass 
transport, starting a
process that anneals separating volumes to form an apparent glass of 
strongly coupled
ions and electrons. Short-time electron spectroscopy provides 
experimental evidence
for complete ionization. The long lifetime of this system, particularly 
its stability with
respect to recombination and neutral dissociation, suggests that this 
transformation
affords a robust state of arrested relaxation, far from thermal 
equilibrium. We argue
that this state of the quenched ultracold plasma offers an experimental 
platform
for studying quantum many-body physics of disordered systems in the 
long-time
and finite energy-density limits. The qualitative features of the 
arrested state fail to
conform with classical models. Here, we develop a microscopic quantum 
description
for the arrested phase based on an effective many-body spin Hamiltonian 
that includes
both dipole-dipole and van der Waals interactions. This effective model 
offers a way
to envision the quantum disordered non-equilibrium physics of this system.