Studies of Quantum Magnetism with Magnetic Resonance and Thermodynamic Measurements

我的团队的研究将主要涉及材料中的磁性研究，旨在揭示和理解物质的新量子状态。这通常是通过研究所谓的受挫磁铁来实现的，在这种磁铁中，不同的能量相互作用之间存在竞争，因此它们不能同时得到满足。在这样的系统中，人们希望排除普通的磁序，获得奇特的基态。例如，我们将研究被称为自旋冰的受挫材料，其中的基本激发可以描述为磁单极子，以及量子自旋液体材料，其中可能存在异常的量子纠缠基态。我的团队还将研究被称为多铁性的材料，这种材料结合了磁性和电极化，可能会展示受挫磁性的一些首批应用。最后，我们还将研究各种导电系统，在这些系统中，多个自由度(包括磁性)和电子之间的强相互作用导致了有趣的物质量子相。 我们将采用的主要研究技术是固体核磁共振和磁化率测量。当磁化率测量高精度地显示不同磁性贡献的总和时，核磁共振可以分离出不同的成分，并揭示样品内部的磁场分布。因此，这种组合方法可以简明扼要地总结为探测样品内部和外部的磁性。这两种高度互补的技术在非常广泛的温度范围内，从室温到绝对零度以上20 MK，这两种高度互补的技术的独特组合，将使我的研究小组能够探索令人兴奋的量子材料，并做出深刻的发现。

My group's research will primarily involve the study of magnetism in materials and will aim to expose and understand new quantum states of matter. Often this will be done by studying so-called frustrated magnets in which there is a competition between different energetic interactions so that they cannot all be simultaneously satisfied. The hope in such systems is to preclude ordinary magnetic order and obtain exotic ground states. For example, we will study frustrated materials called "spin ice" in which the basic excitations can be described as magnetic monopoles, as well as quantum spin liquid materials in which there may exist unusual quantum-entangled ground states. My group will also research materials known as multiferroics, which combine magnetism and electric polarization and may show some of the first applications for frustrated magnetism. Finally we will also study various conducting systems in which many degrees of freedom (including magnetism) and strong interactions between electrons lead to interesting quantum phases of matter. The primary research techniques that we will employ are solid-state nuclear magnetic resonance (NMR) and magnetic susceptibility measurements. Where susceptibility measurements reveal the sum of different magnetic contributions with high precision, NMR can separate out the different components and reveal the distribution of magnetic fields inside a sample. Thus this combined approach may be succinctly summarized as probing the magnetism both inside and outside of a sample. The unique combination of these two highly complementary techniques, over a very broad range of temperatures, from room temperature down to 20 mK above absolute zero, will position my research group to explore exciting quantum materials and make profound discoveries.