Critical velocity, hysteresis, and noflow puzzles

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Critical velocity, hysteresis, and no-flow
puzzles
Nikolay Prokofev UMass, Amherst
Boris Svistunov UMass, Amherst
Lode Pollet ETH , Zurich
Dmitrii Fil IPLT, Kharkov

Sergei Shevchenko IPLT, Kharkov
Supersolid 2009, Banff
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Outline
- Question again where does the hysteresis come
from?
- Here is another one How can NCRI be
reconciled with no-pressure equilibration?
Can an external
object move in the supersolid?
Out-of-equilibrium heating of the SF-carring
subsystem
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Critical velocity proper army manual (F.
Wilczek)
For we get
not
Remant vorticity?
cannot move across sample in 1ms
20 min
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Ideal , regular crystal insulator
Scenario
Network of dislocations with SF cores
Dislocation network at finite T is (i) mobile

(ii) in Shevchenko state
Superfluid state AC measurements
Normal state thermodynamics, DC measurements
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1D phonons
Phase slip
x
x
Energy is injected into the 1D phonon subsystem.
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kink
Cutting the trees
Energy is injected into the 1D kink subsystem.
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from experimental parameters for the quality
factor and specific heat
The amount of energy injected into the
SF-subsystem may increase its temperature, if
the SF-subsystem is isolated
Heat exchange with the bulk solid
c
c
Kinematically forbidden for c gt c
Higher power in T
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Two 1D phonons ? one bulk phonon
or
If equilibration between the bulk and the
SF-subsystem is broken then
with determined by
Hysteresis dislocations have to be mobile to
cut the trees or in
Shevchenko state to have phase slips.
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NCRI vs no-flow
Genuine supersolid
Genuine supersolid
We do NOT expect Pressure to equilibrate!
Iron rods
Topology of lattice sites
Steel
Steel
The ball will NOT move!
water
vacancy gas
Genuine supersolid
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complete equilibration would require
Disregarding frictionless vs. dissipative flow of
vacancies Supersolid finite-T classical
solid, i.e. will NOT relax to zero.
Expected relaxation is in the mbar range
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Conclusions
Small and hysteresis may be argued to
originate in the out-of-equilibrium heating of
the SF-carrying sybsystem
Complete pressure equilibration is NOT expected
in the supersolid.
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