论文标题
两光子驱动的镁对共振作为旋转序列的签名
Two-photon driven magnon-pair resonance as a signature of spin-nematic order
论文作者
论文摘要
从理论上讲，我们在完全极化的挫折磁铁中，在一个不太可见的自旋纽人有序相位的完全极化的沮丧磁体中，由激光或电磁波驱动的非线性磁共振。通常，在自旋纽马磁体的饱和状态下，镁对和镁对（两麦克农结合状态）均以低能激发作用。他们的激发能量通常在Terahertz（THZ）或Gigahertz范围内。具有角动量2 $ \ hbar $的镁对通过同时吸收两个光子可以激发，并且如果施加的THZ激光器足够强，则会发生这种多光子过程。我们计算了具有磁杆（$ \ hbar $）和镁对（2 $ \ hbar $）的沮丧的四旋链系统的激光驱动磁化动力学，就像激发相似，类似于带有旋转固定相的宏观沮丧的磁铁。我们估计激光的磁场强度，以实现两种光子吸收，并考虑到使用Lindblad方程的耗散效应。我们表明，具有0.1-1.0 Tesla的AC磁场的激光激光足以观察到镁对共振。
We theoretically study the nonlinear magnetic resonance driven by intense laser or electromagnetic wave in a fully polarized frustrated magnet near a less-visible spin-nematic ordered phase. In general, both magnons and magnon pairs (two-magnon bound state) appear as the low-energy excitation in the saturated state of spin-nematic magnets. Their excitation energies are usually in terahertz (THz) or gigahertz range. Magnon pairs with angular momentum 2$\hbar$ can be excited by the simultaneous absorption of two photons, and such multi-photon processes occur if the applied THz laser is strong enough. We compute laser-driven magnetic dynamics of a frustrated four-spin system with both magnon ($\hbar$) and magnon-pair (2$\hbar$) like excitations which is analogous to a macroscopic frustrated magnet with a spin nematic phase. We estimate the required strength of magnetic field of laser for the realization of two photon absorption, taking into account dissipation effects with the Lindblad equation. We show that intense THz laser with ac magnetic field of 0.1-1.0 Tesla is enough to observe magnon-pair resonance.
