Kumawat Reshma, Farswan Shubham, Kaur Simranjeet, Bhatia Smriti, Sen Kaushik
Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
J Phys Condens Matter. 2024 Sep 16;36(49). doi: 10.1088/1361-648X/ad75db.
Raman scattering is an excellent method for simultaneously determining the dynamics of lattice, spin, and charge degrees of freedom. Furthermore, polarization selection rules in Raman scattering enable momentum-resolved quasiparticle dynamics. In this review, we highlight the potential of Raman scattering in probing magnetic quasiparticles or excitations in various magnetic materials. We demonstrate how temperature-dependent Raman scattering data can confirm the existence of magnons in long-range ordered magnets and fractionalized excitations in Kitaev spin liquid candidates. To make this review easily understandable to novices, we provide background information on magnons and fractionalized excitations, and explain how they become visible in the Raman scattering process. We also show how to estimate magnetic exchange interactions from the data. For both types of magnetic materials, we discuss the impact of spin-phonon coupling on the lineshape of the phonon modes. In terms of materials, we present magnetic Raman scattering data of antiferromagnetic SrIrOand LaCuO, ferromagnetic CrImonolayers, and Kitaev spin liquid candidates-RuCland-LiIrO. Overall, our review demonstrates the versatility of the Raman scattering technique in probing quasiparticles in magnetic quantum materials. The review aims to inform young experimental researchers about the potential of Raman scattering, thereby motivating them to use this technique in their research.
拉曼散射是一种同时确定晶格、自旋和电荷自由度动力学的优秀方法。此外,拉曼散射中的偏振选择规则能够实现动量分辨的准粒子动力学。在这篇综述中,我们强调了拉曼散射在探测各种磁性材料中的磁性准粒子或激发方面的潜力。我们展示了温度依赖的拉曼散射数据如何能够证实长程有序磁体中磁振子的存在以及基泰夫自旋液体候选材料中的分数化激发。为了使新手易于理解这篇综述,我们提供了关于磁振子和分数化激发的背景信息,并解释了它们如何在拉曼散射过程中显现出来。我们还展示了如何从数据中估计磁交换相互作用。对于这两种类型的磁性材料,我们讨论了自旋 - 声子耦合对声子模式线形的影响。在材料方面,我们展示了反铁磁体SrIrO和LaCuO、铁磁体CrI单层以及基泰夫自旋液体候选材料RuCl和LiIrO的磁性拉曼散射数据。总体而言,我们的综述展示了拉曼散射技术在探测磁性量子材料中的准粒子方面的多功能性。这篇综述旨在让年轻的实验研究人员了解拉曼散射的潜力,从而激励他们在研究中使用这项技术。