ISSN:
1434-6036
Keywords:
PACS. 74.70.Dd Ternary, quaternary and multinary compounds (including Chevrel phases, borocarbides ets.) - 76.80.+y Mössbauer effect; other -ray spectroscopy
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract: In a previous study of the Er3+ spin relaxation rate in ErNi2B2C (Bonville et al., Z. Phys. B 101, 511 (1996)), we found that its thermal dependence showed an anomaly at the superconducting transition temperature ( = 10.5 K). This behaviour could be related either to a superconductivity-related change in the density of conduction band states to which the Er3+ spin is coupled or alternatively to the slowing down of the Er3+ spin fluctuations due to the development of short range magnetic order above the long range ordering temperature ( 6 K). To identify the origin of the anomaly, we compared the results of a 166Er Mössbauer study on Er(Ni0.975Co0.025)2B2C where is depressed to 4 K and remains near 6 K, and on Er0.2Y0.8Ni2B2C where = 14.2 K and there is no long range order. We conclude the relaxation anomaly is due to the onset of short range magnetic order. The normal state coupling of the 4 f-conduction electron exchange in the partially diluted sample is = 0.015. We also present 166Er Mössbauer measurements of the hyperfine field in single crystal ErNi2B2C which provide information concerning the direction of the magnetically ordered Er3+ moments in the superconducting phase.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s100510070181
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