Thursday's seminar

[CM ICTP - Trieste]

CONDENSED MATTER AND STATISTICAL PHYSICS SECTION
	
INFORMAL SEMINAR on
Disorder and strong electron correlations





Thursday, 6 April    -    11:00 a.m.



Room 239,  Main Bldg.- II floor



G. TKACHOV  ( University of Regensburg )


"Fluxoid states and oscillations of the Josephson current in 
low-dimensional weak"


	Abstract

I will discuss charge transport in a specific type of low-dimensional 
normal metal (N)-superconductor (S) systems which can exhibit nearly 
reflectionless tunneling of Cooper pairs even for low-transparency 
interfaces.  In SNS structures such reflectionless tunneling results in 
anomalous Andreev bound states that make a dominant contribution to the 
Josephson current. An interesting situation occurs in systems with 
multiply connected superconductors where the Andreev bound states are 
coupled to an external magnetic flux via the fluxoid quantization.  In 
this case magnetic oscillations of the critical Josephson current 
analogous to the Little-Parks effect are predicted.  I will also 
discuss experiments presumably demonstrating the reflectionless 
tunneling of Cooper pairs.