X G Zheng
Saga University, Japan
Title: Geometrically frustrated magnetism and quantum atomic properties in hydroxyl salts
Biography
Biography: X G Zheng
Abstract
Hydroxyl salts exist in nature. The most familiar might be the hydroxyl chloride Cu2(OH)3Cl (atacamite), which forms naturally on copper and bronze as a green patina and is widely recognized as imparting characteristics to the Statue of Liberty. But only in recent years, their intriguing magnetism, with prominent geometric frustration, have been uncovered by us. Geometrically frustrated magnets, in which localized magnetic moments on triangular, kagome or pyrochlore lattices interact through competing exchange interactions, have been of intense recent interest due to the diversity in the exotic ground states that they display and potential applications that they may bring out. The diverse experimental reports of unconventional magnetic properties also provide challenge and testing ground for theoretical models. Till now, we have discovered that the hydroxyl salts of the type M2(OH)3Cl or M(OH)Cl, where M is a magnetic ion of Cu2+, Ni2+, Co2+, Fe2+, or Mn2+, are geometrically frustrated magnets resulting from their crystal structures as illustrated in figure I. Furthermore, in some of these compounds we found the occurrence of ferroelectricity with multiferroic features. In this talk, I will review our experimental results on hydroxyl salts, together with a brief introduction to a less-known experimental technique mSR.