Collective modes in nodal line semimetals

Abstract

Recently, the nodal line semimetals have attracted considerable interests in condensed matter physics. We show that their distinct band structure can be detected by measuring the collective modes. In particular, we find that the dependence of the plasmon frequency ω p on the electron density n follows a ω p ∼ n 1/4 law in the long wavelength limit. Our results will be useful in the ongoing search for new candidates of nodal line semimetals.

Atomic Vacancy Control and Elemental Substitution in a Monolayer Molybdenum Disulfide for High Performance Optoelectronic Device Arrays

“…[30] The STEM image of the pristine MoS 2 (Figure 3d) shows the threefold coordinated lattice consisting of high-intensity Mo and low-intensity S atoms (Figure 3d), which can be visualized by superimposing the atomic model of perfect crystalline MoS 2 (the right schematic in Figure 3d). [31] For the further verification, the normalized intensities of STEM are simulated ( Figure S7, Supporting Information) and the statistical distributions of both experimental and simulated sulfur intensities are plotted as a histogram (Figure 3g; Figure S8, Supporting Information). The extracted content of two S atoms (2S), single sulfur vacancy (1S V ), and double sulfur vacancies (2S V ) in the pristine MoS 2 monolayer are 98.06%, 1.50%, and 0.21%, respectively, which corresponds to the density of 2.2 × 10 15 , 3.4 × 10 13 , and 4.8 × 10 12 cm −2 , respectively.…”

Tunable Weyl Points in Periodically Driven Nodal Line Semimetals

“…The main feature of the band structures of DSMs and WSMs is the linear bandtouching points ("Dirac points" and "Weyl points"), which are responsible for most of their interesting properties, including novel phenomena induced by the chiral anomaly [32][33][34][35][36][37][38][39][40][41][42][43][44]. NLSMs [45][46][47][48][49][50][51][52][53][54][55][56][57][58][59][60][61][62][63] differ in that they contain band-touching lines or rings [107], away from which the dispersion is linear.In this Letter we show that driving NLSMs by a circularly polarized light (CPL) creates WSMs, namely, nodal lines become nodal points under radiations. Our work was motivated by recent progress in Floquet topological states [64][65][66][67][68][69][70][71][72][73][74][75][76]…”

“…The main feature of the band structures of DSMs and WSMs is the linear bandtouching points ("Dirac points" and "Weyl points"), which are responsible for most of their interesting properties, including novel phenomena induced by the chiral anomaly [32][33][34][35][36][37][38][39][40][41][42][43][44]. NLSMs [45][46][47][48][49][50][51][52][53][54][55][56][57][58][59][60][61][62][63] differ in that they contain band-touching lines or rings [107], away from which the dispersion is linear.…”

Polarization‐dependent anisotropic Raman response of CVD‐grown vertically stacked MoS2 layers

“…[41] When 1H-MoS 2 layers are stacked one by one, hexagonal 2H and rhombohedral 3R phases can be formed. [18,42] In bilayer MoS 2 , the twisting angle between adjacent layers is 0 for 3R, whereas the interlayer stacking configuration of 2H is twisted 60 with respect to the adjacent layer. [13,18,42] The optical microscope and AFM topographic images in Figure 1a,b suggest that the stacking order of MoS 2 most likely corresponds to the 3R phase.…”