论文标题
量子材料中的木农 - 两极元理论
Theory of magnon-polaritons in quantum Ising materials
论文作者
论文摘要
我们提出了量子iSing材料中的木量摩尔龙的理论，并开发出一种形式主义，描述了光与物质之间的耦合，因为它通过其量子临界点进行了调整。该理论应用于具有多级单位汉密尔顿人的Ising材料，其中存在多种磁通模式，例如绝缘磁铁Lihof $ _4 $。我们发现，镁 - 光子耦合强度可以通过施加的横向场来调节，并在量子ising材料中存在的软模式与光子谐振器模式之间的耦合在材料的量子临界点处有分歧。当光耦合到移动旋转或原子时，固定的旋转系统不会表现出预期的磁管反应。没有磁管反应，人们期望发散的镁 - 光子耦合强度会导致超级量子相变。但是，这忽略了任何实际系统中存在阻尼和脱干的影响。我们表明，阻尼和变质可能会阻止超级量子相变，并导致软木元素模式和谐振器模式之间的弱耦合。该理论的结果应用于微波谐振器中模型系统LIHOF $ _4 $的实验数据。
We present a theory of magnon-polaritons in quantum Ising materials, and develop a formalism describing the coupling between light and matter as an Ising system is tuned through its quantum critical point. The theory is applied to Ising materials having multilevel single-site Hamiltonians, in which multiple magnon modes are present, such as the insulating Ising magnet LiHoF$_4$ . We find that the magnon-photon coupling strengths may be tuned by the applied transverse field, with the coupling between the soft mode present in the quantum Ising material and a photonic resonator mode diverging at the quantum critical point of the material. A fixed system of spins will not exhibit the diamagnetic response expected when light is coupled to mobile spins or atoms. Without the diamagnetic response, one expects a divergent magnon-photon coupling strength to lead to a superradiant quantum phase transition. However, this neglects the effects of damping and decoherence present in any real system. We show that damping and decoherence may block the superradiant quantum phase transition, and lead to weak coupling between the soft magnon mode and the resonator mode. The results of the theory are applied to experimental data on the model system LiHoF$_4$ in a microwave resonator.
