Normal-State Spin Dynamics and Temperature-Dependent Spin Resonance Energy in an Optimally Doped Iron Arsenide Superconductor

Date & Time
7 September 2009 (Mon) 14:30 – 16:00
Place
8F large seminar room, Sengen site
Speaker
Dr. Vladimir Hinkov
Affiliation
Max-Planck-Institute for Solid State Research
Title
"Normal-State Spin Dynamics and Temperature-Dependent Spin Resonance Energy in an Optimally Doped Iron Arsenide Superconductor
Abstract
Using inelastic neutron scattering we have studied the spin excitations in optimally doped BaFe(1.85)Co(0.15)As(2) (Tc = 25 K) over a wide range of temperatures and energies. I will contrast our results to findings in cuprates and heavy fermion superconductors, and discuss their implications to theory. In particular, we find that in contrast to cuprates, the spectrum is in good agreement with predictions of the theory of nearly antiferromagnetic metals, without complications arising from a pseudogap or competing incommensurate spin-modulated phases. This simplifies the theoretical treatment, and our data provide the foundation for the development of quantitative theories of magnetically mediated superconductivity in the iron arsenides.
Contact
Dr. Hiroyuki Yamase(山瀬博之)