论文标题
dirac旋转液体中的单极约瑟夫森效应
Monopole Josephson Effects in a Dirac Spin Liquid
论文作者
论文摘要
狄拉克旋转液体(DSL)是无间隙的状态,但由于描述它们的有效田间理论 - (2+1) - 维量子量子电动力学(QED $ _3 $)。此外,已知DSL是各种看似无关的有序状态的“母体状态”,例如抗铁磁体和价值键固体,从某种意义上说,可以通过凝结出现量规场的磁性单子来获得有序状态。有效田间理论中的运算符(例如新兴电场)是否可以在外部诱导和测量?在这项工作中,我们利用父状态图片认为答案是肯定的。我们提出了一系列的“单极约瑟夫森效应”,当两个有序状态被父级DSL的区域分离时。特别是,我们表明可以诱导AC单极约瑟夫森效应,该效应表现为自旋液体中的AC新兴电场,并伴有可测量的自旋电流。此外,我们表明,这种新兴电场可以测量为拉曼散射中的尖锐可调峰。这项工作提供了理论上的原理证明,即可以使用更多传统状态在外部诱导,操纵和探测自旋液体中的新出现量规场,该状态提供了一个通用平台来研究外来的自旋相。
Dirac Spin liquids (DSLs) are gapless featureless states, yet interesting by virtue of the effective field theory describing them -- (2+1)-dimensional quantum electrodynamics (QED$_3$). Further, a DSL is known to be a "parent state" of various seemingly unrelated ordered states, such as antiferromagnets and valence bond solids in the sense that one can obtain ordered states by condensing magnetic monopoles of the emergent gauge field. Can operators in the effective field theory, such as the emergent electric field, be externally induced and measured? In this work, we exploit the parent state picture to argue that the answer is yes. We propose a range of "monopole Josephson effects" that arise when two ordered states are separated by a region of the parent DSL. In particular, we show that one can induce an AC monopole Josephson effect, which manifests itself as an AC emergent electric field in the spin liquid, accompanied by a measurable spin current. Further, we show that this AC emergent electric field can be measured as a sharp tunable peak in Raman scattering. This work provides a theoretical proof of principle that emergent gauge fields in spin liquids can be externally induced, manipulated, and probed using more conventional states, which offers a generic platform for studying the exotic spin phases.