[超导国家重点实验室学术报告]三角晶格稀土氧族化合物AReCh2中自旋激发的研究进展

阻挫磁性是当今凝聚态物理研究的重要内容。虽已经历长期探索，在自旋阻挫材料中寻找量子自旋液体仍然是一个富有挑战的课题。在许多已知的量子自旋液体候选材料中，磁性杂质、结构缺陷、无序等的存在都会影响人们对其磁基态的判断，从而降低其量子自旋液体基态的可信度。因而，寻找不存在结构缺陷、无序的阻挫磁性材料是实现量子自旋液体的重要前提。2018年出现的具有铜铁矿结构的三角晶格稀土氧族化合物AReCh2 (A为碱金属，Re为稀土元素，Ch为氧族元素)中被证明不易存在结构缺陷和无序，而且很多AReCh2材料在实验中都没有形成磁有序，因此被认为是实现量子自旋液体态的理想材料体系。随后的非弹性中子散射也相继在NaYbO2，NaYbSe2等材料中观测到了连续的自旋激发，被认为是分数化的自旋子激发，为量子自旋液体态的存在提供了重要证据。

[超导国家重点实验室学术报告]Electronic state control in layered quantum materials

The multifunctional behaviors of quantum materials are driven by the intricate interplay between charge, orbital and spin degrees of freedom. Advances in modern field-effect devices allow for unprecedented control of these degrees of freedom, revealing a plethora of exotic physical phenomena such as superconductivity and long-range magnetic order. In this talk, I will provide an overview of our recent progress in controlling the emerging physical phenomena in layered quantum devices and how they offer new insights to the underlying physics. First, I will discuss the observation of a spontaneous anomalous Hall effect, a trademark of time-reversal symmetry breaking, in a doped layered polar semiconductor. Notably, the magnitude of anomalous Hall conductivity can be enhanced by tuning the carrier density, which sheds new light on the interplay of magnetic and ferroelectric-like responses [1]. Next, I will present recent results on the electric field control at the interfaces of ionic gated tellurium thin flake devices, demonstrating a fourfold increase in the Rashba spin-orbit coupling coefficient.

超导实验室学术报告1

超导实验室学术报告
超导实验室学术报告