Condensed-Matter Physics & Materials Science Seminar
"Room-temperature magnetic spiral order induced by disorder"
Presented by Christopher Mudry, Paul Scherrer Institut, Switzerland
Monday, July 2, 2018, 1:30 pm
ISB Bldg. 734 Conf. Rm. 201 (upstairs)
Hosted by: Alexei Tsvelik
Upon cooling, the compound YBaCuFeO5 undergoes a phase transition to an antiferromagnetic long-range ordered phase. Upon further cooling, a second phase transition to a magnetic spiral phase takes place. The latter transition temperature depends on the sample preparation and can reach room temperature. We propose a mechanism to explain the transition to a magnetic spiral ordered phase due to frustrating magnetic interactions that are introduced randomly along a single crystallographic direction as caused by a particular type of chemical disorder. This mechanism could open the way to high-temperature multiferroism.