Effects of Geometrical Spin Frustration on Triangular Spin Tubes Formed in CsCrF_4 and α-KCrF_4
Effects of Geometrical Spin Frustration on Triangular Spin Tubes Formed in CsCrF_4 and α-KCrF_4
复制标题
几何自旋挫败对CsCrF_4和α-KCrF_4中形成的三角形自旋管的影响
DOI：
10.1143/jpsj.80.084714
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发表时间：
2011
影响因子：
1.7
通讯作者：
Y.Miura
中科院分区：
文献类型：
--
作者：
H.Manaka;T.Etoh;Y.Honda;N.Iwashita;K.Ogata;N.Terada;T.Hisamatsu;M.Ito;Y.Narumi;A.Kondo;K Kindo;Y.Miura
我们对CsCrF 4和α-KCrF 4中由等边和不等边三角形自旋管组成的高质量S =3/2多晶化合物分别进行了X射线衍射、磁化率、热容、高场磁化强度和电子自旋共振实验。在这两种化合物中，三角形平面内的几何自旋阻挫与沿管的一维性沿着共存。在CsCrF_4中，在1.5K以上没有出现磁性长程有序，这与先前的报道[H. Manakaet al.：J.Phys.Soc.Jpn.78（2009）093701]。在低温（T）区，热容量出现T线性分量，磁化曲线显示有限的初始斜率。因此，CsCrF 4是一种无间隙的自旋液体状态，不仅在每个等边三角形中，而且在沿着管中包含共振自旋单重态对。而α-KCrF 4在TN_1 = 2.5（1）K和TN_2 = 4.0（1）K时发生了连续的磁相变，这是因为在每个非等边三角形中通过三条Cr-F-Cr路径的超交换相互作用失去了平衡。
We conducted X-ray diffraction, magnetic susceptibility, heat capacity, high-field magnetization, and electron spin resonance experiments on high-quality polycrystallineS=3/2 compounds consisting of equilateral and non-equilateral triangular spin tubes in CsCrF4and α-KCrF4, respectively. In both compounds, geometrical spin frustration in the triangular planes coexists with one-dimensionality along the tubes. In CsCrF4, no magnetic long-range order appeared above 1.5 K, which agrees with a prior report [H. Manakaet al.: J. Phys. Soc. Jpn.78(2009) 093701]. In a low temperature (T) regime,T-linear component of heat capacity appeared and magnetization curves showed finite initial slopes. As a result, CsCrF4consists of a gapless spin-liquid state encompassing resonating spin-singlet pairs not only in each equilateral triangle but also along the tubes. In contrast, for α-KCrF4, successive magnetic phase transitions occurred atTN1= 2.5(1) K and atTN2= 4.0(1) K because superexchange interactions through three Cr–F–Cr paths in each non-equilateral triangle lost their equilibrium.