Development of Highly Thermal-Conducting Spin-Materials and Elucidation of the Mechanism of the Thermal Conduction

我们已经生长了低维量子自旋系统的高质量单晶，测量了热导率，并研究了由于自旋导致的大热导率的机制，以开发新的电绝缘和高热导率的材料。结果，我们发现了几个新的因素，由于大的热导率自旋如下。（1）均匀的最近邻交换相互作用。（2）海森堡自旋系统。（3）大量子自旋数。（4）磁激发的玻色-爱因斯坦凝聚态。（5）由于自旋挫折而引起的大的自旋波动。

We have grown high-quality single crystals of low-dimensional quantum-spin systems, measured the thermal conductivity and investigated the mechanism of large thermal conductivity due to spins, in order to develop new electrically insulating and highly thermal-conducting materials using thermal conduction due to spins. As a result, we have found new several factors of large thermal conductivity due to spins as follows. (1)Uniform nearest-neighboring exchange-interaction. (2)Heisenberg spin system. (3)Large quantum-spin-number. (4)Bose-Einstein condensed state of magnetic excitations. (5)Large spin-fluctuations due to spin frustrations.