ELFT HÍRADÓ

[Balogh Judit <baloghj AT szfki.hu>]

Kedves Kollégák, Dear Colleagues,

we present our next Wigner Colloquium talk on February 13th, Wednesday,
at the usual location (KFKI campus, Bldg 1, Meeting room) from 10:00-12:00.

PLEASE NOTE THE UNORDINARY DATE AND TIME !

*Speaker:  Wolfgang Kleemann*

https://www.researchgate.net/profile/Wolfgang_Kleemann


 Title:
 *Novel states and functions of magnetic and polar solids at the nanoscale*

https://indico.kfki.hu/event/953/

Abstract:

/Magnetic and electric dipolar interactions give rise to novel states in 
aggregates of nanoparticles (NPs). In this talk I shall first report on 
Supermagnetism, the occurrence of different states of magnetic single 
domain NPs in dense systems. At high densities the superferromagnetic 
state of FeCo NPs reveals domain walls with specific kinetics. The 
mesoscopic superspinglass state of dilute FeCo NPs embedded in a film of 
Al2O3 at low density resembles microscopic spin glasses to a large 
extent. Superspinglasses belong to the family of Ferroic Glasses along 
with so-called ‘Relaxor Ferroelectrics’. These are disordered ionic 
solid solutions like PbMg1/3Nb2/3O3, where NPs emerge as polar 
nanoregions pinned by intrinsic alloy quenched random electric fields 
and condense into a cluster glass ground state. Magnetic NPs have found 
strong interest in artificial Nanocomposites with specific interface 
couplings. I report on bilayered films with stress-strain coupling in 
BaTiO3/CoFe2O4 and with magnetic exchange coupling in Cr2O3/[Pt/Co/Pt], 
respectively. Both systems appear promising for applications in novel 
RAM devices.///