Научная сессия и заседание Учёного совета

Повестка дня:

1. Е. Вавилова, М. Яковлева, H.-J. Grafe, S. Zimmermann, А.Альфонсов, H. Luetkens, H.-H. Klauss, А. Малюк, S. Wurmehl, B. Büchner, В.Катаев. Основное состояние и низкоэнергетическая магнитная динамика фрустрированной шпинели CoAl2O4 по данным ЯМР, ЭПР и мюонной спектроскопии.

We report a combined experimental study of magnetic properties of a single crystal of the frustrated diamond lattice antiferromagnet CoAl2O4  with Co 2+   electron spin resonance, Al  nuclear magnetic resonance, and muon spin rotation/relaxation techniques. With our local probes, we show that the frustration of spin interactions and the Co/Al site disorder strongly affect the spin dynamics. The experimental results evidence inhomogeneous and slow magnetic fluctuations and the occurrence of short-range electron spin correlations far above a characteristic temperature T =8K at which the spin system turns into in a quasistatic state. Our data indicate that this spin order is likely short range and unconventional with spin fluctuations persistent even at T≪8K. The results of three spectroscopy techniques highlight a nontrivial role of structural disorder for the magnetism of a frustrated diamond spin lattice at the proximity to the critical point.

  2. Разное