Friday, 4 October 2013

Scientists directly observe bound states of elementary magnets in ferromagnetic quantum crystals

more »

Simulating solid state properties with precisely controlled quantum systems is an important goal of the Quantum Many-Body Systems Division at MPQ. Now the team around Professor Immanuel Bloch (Chair for Experimental Physics at the Ludwig-Maximilians-Universität Munich and Director at MPQ) has come again a step closer to it – to be precise, to the understanding of processes in ferromagnetic solid state crystals in which elementary excitations, so-called magnons, can emerge. About 80 years ago the German physicist Hans Bethe deduced from a theoretical model that in one-dimensional ferromagnets two of those elementary magnetic excitations can form a bound state. Like two tiny bar magnets, two atoms can stick together and form a new particle that propagates in the crystal. The MPQ team has now succeeded to observe these most elementary mobile magnetic domains, the two-magnon states, directly and to resolve their dynamics with time-resolved measurements. This study complements conventional spectroscopy in solid state crystals which yields information on momentum and frequency of the magnetic excitations. Bound states of excitations can influence the thermal conductance properties of low-dimensional ferromagnets or the propagation speed of quantum information in magnetic wires.



Zazzle Space market place

No comments:

Post a Comment