Thursday's seminar

[CM]

SEMINAR on    Disorder and strong electron correlations



Thursday, 28 May      -  11:00 a.m.


Seminar Room,  Leonardo Building - first floor



F. FRANCHINI    ( The Abdus Salam ICTP )



"Nonlinear dynamics of spin and charge in spin-Calogero model"



Abstract

The fully nonlinear dynamics of spin and charge in spin-Calogero model 
is studied.  The latter is an integrable one-dimensional model of 
quantum spin-1/2 particles interacting through inverse-square 
interaction and exchange.  Classical hydrodynamic equations of motion 
are written for this model in the regime where gradient corrections to 
the exact hydrodynamic formulation of the theory may be neglected.  In 
this approximation variables separate in terms of dressed Fermi momenta 
of the model.   Hydrodynamic equations reduce to a set of decoupled 
Riemann-Hopf (or inviscid Burgers') equations for the dressed Fermi 
momenta.  We study the dynamics of some non-equilibrium spin-charge 
configurations for times smaller than the time-scale of the gradient 
catastrophe.  We find an interesting interplay between spin and charge 
degrees of freedom.  In the limit of large coupling constant the 
hydrodynamics reduces to the spin hydrodynamics of the Haldane-Shastry 
model.