Neutron scattering study of spin fluctuations in Y(Mn1-xAlx
Neutron scattering study of spin fluctuations in Y(Mn1-xAlx
复制标题
Y(Mn1-xAlx)中自旋涨落的中子散射研究
DOI：
10.1103/physrevb.38.4796
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
Shirane
中科院分区：
文献类型：
--
作者：
Motoya;Freltoft;Böni;Shirane
对一系列伪二元金属间化合物Y(Mn/sub 1-//sub x/Al/sub x/)/sub 2/进行了弹性和非弹性中子散射测量。远距反铁磁阶低于T/sub /约100在YMn/sub 2/中，只有5%的锰原子被铝原子取代，K就会坍塌。在这些化合物中，通过散射中子谱的能量宽度的变化以及磁化率测量中场迟滞的开始，可以清楚地表明自旋玻璃跃迁。在x = 0.10的化合物中，自旋涨落S的振幅随温度变化不明显，而在YMn/sub 2/中，自旋涨落S在T/sub N/时下降30%以上，然后随着温度的升高逐渐增加。自旋涨落的空间相关性至少持续到760 K，这与在YMn/ sub2 /中观察到的行为相似，但与简单局域电子磁体的特征有很大不同。
Elastic and inelastic neutron-scattering measurements have been made on a series of pseudobinary intermetallic compounds Y(Mn/sub 1-//sub x/Al/sub x/)/sub 2/. Long-range antiferromagnetic order below T/sub N/approx.100 K in YMn/sub 2/ has been shown to collapse by substitution of only 5% of the manganese atoms by aluminum atoms. In these compounds, a spin-glass transition has been clearly indicated by a change in the energy width of the scattered-neutron spectrum, as well as by the onset of field hysteresis in susceptibility measurements. In the compound with x = 0.10, the amplitude of spin fluctuations S does not change appreciably with temperature, whereas in YMn/sub 2/ it drops by more than 30% at T/sub N/ and then increases gradually with increasing temperature. A considerable degree of spatial correlations of spin fluctuations persists up to at least 760 K, which is similar to the behavior observed in YMn/sub 2/ but quite different from the characteristics of simple localized-electron magnets.