Temperature and magnetic field induced multiple magnetic transitions inDyAg2

Abstract

The magnetic properties of the rare-earth intermetallic compoundDyAg2 are studied in detail with the help of magnetization and heat capacity measurements.It is shown that the multiple magnetic phase transitions can be induced inDyAg2 both by temperature and magnetic field. The detailed magnetic phase diagram ofDyAg2 is determined experimentally. It was already known thatDyAg2 undergoes an incommensurate to commensurate antiferromagnetic phase transition close to10 K. The present experimental results highlight the first order nature of this phase transition,and show that this transition can be induced by magnetic field as well. It is further shown thatanother isothermal magnetic field induced transition or metamagnetic transition exhibited byDyAg2 atstill lower temperatures is also of first order nature. The multiple magnetic phase transitions inDyAg2 give rise to large peaks in the temperature dependence of the heat capacitybelow 17 K, which indicates its potential as a magnetic regenerator material forcryocooler related applications. In addition it is found that because of the presenceof the temperature and field induced magnetic phase transitions, and becauseof short range magnetic correlations deep inside the paramagnetic regime,DyAg2 exhibits a fairly large magnetocaloric effect over a wide temperature window, e.g., between10 and 60 K.