自旋阻挫重费米子体系中的量子相变

近藤效应和RKKY交换相互作用的竞争决定了多数重费米子化合物的基态性质。通过压力、磁场等非热力学参量调控，该类材料能够在绝对零温附近实现费米液体和磁有序相之间的连续转变，提供了研究量子相变的理想平台。另一方面，在绝缘的量子磁体中，自旋阻挫引起的量子涨落抑制低温下长程磁有序的发生，导致自旋液体相等新奇物态的产生。在近藤晶格中引入自旋阻挫将给重费米子材料提供一个新的调控维度，深刻改变该类材料的量子临界相图，是重费米子材料领域的一个新颖研究方向。文章首先介绍阻挫重费米子体系的研究背景，然后针对CePdAl的物性展开讨论，探讨阻挫对重费米子材料量子临界物性的影响以及量子临界相的普适性。

Quantum phase transitions in geometrically frustrated heavy-fermion compounds

The competition between the Kondo effect and the Ruderman- Kittel- Kasuya-Yosida exchange interaction determines the ground state of most heavy- fermion compounds. By employing non-thermal tuning parameters like pressure and magnetic field, Fermi liquids and magnetically ordered phases can be tuned smoothly to each other in these compounds, offering an ideal playground for quantum criticality. On the other hand, spin frustration is an effective approach to produce novel quantum phenomena such as spin liquids in insulating quantum magnets. Introducing spin frustration into heavy fermion systems will profoundly affect their ground state, and is emerging as a new research direction. Following a brief introduction to frustrated heavy-fermion compounds, we will first describe our recent work on frustrated CePdAl, and then discuss the observed quantumcritical phase that is intimately related to spin frustration.