E K Zavoiskii Institute for Technical Physics of the RAS, Kazan 420029, Russia.
J Phys Condens Matter. 2014 Jan 15;26(2):026003. doi: 10.1088/0953-8984/26/2/026003. Epub 2013 Dec 10.
The spin dynamics of copper pyrazine dinitrate (Cu(C4H4N2)(NO3)2), a model spin-1/2 Heisenberg antiferromagnetic (AF) chain system, was investigated by means of electron spin resonance (ESR). Using the high-field ESR we evidenced the inequivalence of Cu sites belonging to adjacent spin chains in the ac planes of this compound. It was revealed that the dominating interchain interaction is of zig-zag-type. This interaction gives rise to geometrical frustration strongly affecting the character of AF ordering. Combining our experimental findings with the results of a quasiclassical approach we predict that at low temperatures the system orders in an incommensurate spiral state.
我们通过电子自旋共振（ESR）研究了铜吡嗪二硝酸盐（Cu(C4H4N2)(NO3)2）的自旋动力学，这是一个模型自旋-1/2 海森堡反铁磁（AF）链系统。通过高场 ESR，我们证明了该化合物 ac 面中相邻自旋链的 Cu 位不等价。结果表明，主导的链间相互作用是之字形型。这种相互作用导致强烈影响 AF 有序特征的几何各向异性。将我们的实验结果与准经典方法的结果相结合，我们预测在低温下，系统将以非调谐螺旋状态有序。
