For distribution - revised

[CM ICTP - Trieste]

CONDENSED MATTER SECTION

	
SEMINAR on  Disorder and strong electron correlations



THURSDAY, 31 May   -    11:00 a.m.


Seminar Room,  Main Bldg.- first floor


D. ARISTOV   ( Universität Karlsruhe )


"Luttinger liquids with curvature: Density correlations and Coulomb 
drag effect"

Abstract

	I discuss the effect of the curvature in fermionic dispersion on the 
observable properties of Luttinger liquid (LL).  In the bosonization 
technique the curvature is irrelevant perturbation,  describing the 
decay of LL bosons (plasmon modes).  When possible, I show the 
correspondence between the bosonization and the fermionic approach.  
The most important application of this approach is the analysis of the 
Coulomb drag by small momentum transfer between two LL, which is only 
possible due to curvature.  Analyzing the a.c. transconductivity in the 
one-dimensional drag setup,  I confirm the results by Pustilnik {\em et 
al.} for $T-$dependence of drag resistivity,  $R_{12} \sim T^2$ at high 
and $R_{12} \sim T^5$ at low temperatures.  The bosonization allows for 
treating both intra- and inter-wire electron-electron interactions in 
all orders, and I calculate the exact prefactors in low-T drag regime.  
The crossover temperature between the two regimes is $T_1 \sim E_F 
\Delta$, with $\Delta$ relative difference in plasmon velocities. I 
show that $\Delta \neq 0$ even for identical wires, due to lifting of 
plasmon degeneracy by interwire interaction, $U_{12}$, leading to 
crossover from $R_{12} \sim U_{12}^2 T^2$ to $R_{12} \sim T^5/U_{12}$ 
at $T \sim U_{12}$.