Prof. Amit Keren (Technion)

Date: Jun. 7, 2009

Title: Nano-Magnets

Abstract: 

Nano magnets (NM) consist of a molecule of magnetic ions coupled by
ferromagnetic or antiferromagnetic interaction. These molecules
crystallize in a lattice where neighboring molecules are magnetically
separated, yielding, at low temperatures, non-interacting giant spins
S. Due to magneto-crystalline anisotropy, the dominant part of the
Hamiltonian is proportional to -S_z^2. When the temperature is much
lower than some anisotropy barrier, the only possible magnetization
relaxation mechanism from Sz=S to Sz=-S is through tunneling, assisted
or hindered by the environment. Thus NM provide model compounds for
testing quantum mechanical concepts such as the stochastic
Landau-Zener theory or interaction of light with matter. In this talk
I will present the NM, some experimental observations, and open
theoretical questions.