Infrared Study of the Spin Reorientation Transition and Its Reversal in the Superconducting State in Underdoped Ba1-xKxFe2As2

• Autoři: MALLETT B.P.P.; MARŠÍK Přemysl; YAZDI-RIZI M.; WOLF Th.; BOHMER A.E.; HARDY F.; MEINGAST C.; MUNZAR Dominik; BERNHARD Christian
• Rok publikování: 2015
• Druh: Článek v odborném periodiku
• Časopis / Zdroj: PHYSICAL REVIEW LETTERS
• Fakulta / Pracoviště MU: Přírodovědecká fakulta
• www: http://journals.aps.org/prl/pdf/10.1103/PhysRevLett.115.027003
• Doi: http://dx.doi.org/10.1103/PhysRevLett.115.027003
• Obor: Fyzika pevných látek a magnetismus
• Klíčová slova: Iron-based superconductors
• Popis: With infrared spectroscopy we investigated the spin-reorientation transition from an orthorhombic antiferromagnetic (o-AF) to a tetragonal AF (t-AF) phase and the reentrance of the o-AF phase in the superconducting state of underdoped Ba1-xKxFe2As2. In agreement with the predicted transition from a single-Q to a double-Q AF structure, we found that a distinct spin density wave develops in the t-AF phase. The pair breaking peak of this spin density wave acquires much more low-energy spectral weight than the one in the o-AF state which indicates that it competes more strongly with superconductivity. We also observed additional phonon modes in the t-AF phase which likely arise from a Brillouin-zone folding that is induced by the double-Q magnetic structure with two Fe sublattices exhibiting different magnitudes of the magnetic moment.

Související projekty

• CEITEC - středoevropský technologický institut