Understanding how symmetry-breaking processes generate order out of disorder is among the most fundamental problems of nature. The scalar Higgs mode - a massive (quasi-) particle - is a key ingredient in these processes and emerges with the spontaneous breaking of a continuous symmetry. Its related exotic and elusive axial counterpart, a Boson with vector character, can be stabilized through the simultaneous breaking of multiple continuous symmetries.
View Article and Find Full Text PDFVertical charge order shapes the electronic properties in layered charge density wave (CDW) materials. Various stacking orders inevitably create nanoscale domains with distinct electronic structures inaccessible to bulk probes. Here, the stacking characteristics of bulk 1T-TaS are analyzed using scanning tunneling spectroscopy (STS) and density functional theory (DFT) calculations.
View Article and Find Full Text PDFSolids undergoing a transition from order to disorder experience a proliferation of topological defects. The melting process generates transient quantum states. However, their dynamic nature with a femtosecond lifetime hinders exploration with atomic precision.
View Article and Find Full Text PDFIn order to understand the superconducting gap nature of a [Formula: see text] single crystal with [Formula: see text], in-plane thermal conductivity [Formula: see text], in-plane London penetration depth [Formula: see text], and the upper critical fields [Formula: see text] have been investigated. At zero magnetic field, it is found that no residual linear term [Formula: see text] exists and [Formula: see text] follows a power-law [Formula: see text] (T: temperature) with n = 2.66 at [Formula: see text], supporting nodeless superconductivity.
View Article and Find Full Text PDFThe pure Kitaev honeycomb model harbors a quantum spin liquid in zero magnetic fields, while applying finite magnetic fields induces a topological spin liquid with non-Abelian anyonic excitations. This latter phase has been much sought after in Kitaev candidate materials, such as α-RuCl. Currently, two competing scenarios exist for the intermediate field phase of this compound (B = 7 - 10 T), based on experimental as well as theoretical results: (i) conventional multiparticle magnetic excitations of integer quantum number vs.
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