Studies on quantum and frustrated spin systems by ultra-low temperature high-field multi-frequency ESR

我们研制了高磁场多频电子自旋共振（ESR）装置，在静磁场下可测量到0.1K，在脉冲磁场下可测量到0.6K，用于研究两种具有显著量子效应和竞争交换相互作用的磁体。我们发现了新的ESR信号高于一个临界场，在那里的能隙消失，这是没有观察到的温度下降到1.3K的前者，和一个ESR共振场的移动后者。

We have developed high magnetic field multi-frequency electron spin resonance (ESR) apparatuses that can measure down to 0.1K in a static magnetic field and down to 0.6K in a pulsed magnetic field to study two kinds of magnets with remarkable quantum effects and competing exchange interactions. We have found novel ESR signals above a critical field where the energy gap vanishes which were not observed at the temperatures down to 1.3K for the former, and the shift of an ESR resonance field for the latter.