In this work, the magnetism of the single crystal Cr 1/3 NbS 2 , which exhibits chiral magnetic soliton lattice (CSL) state, is investigated. The magnetization displays strong magnetic anisotropy when the field is applied perpendicularly and parallel to the c-axis in low field region (H < H S , H S is the saturation field). The critical exponents of Cr 1/3 NbS 2 are obtained as β = 0.370(4), γ = 1.380(2), and δ = 4.853(6), which are close to the theoretical prediction of three-dimensional Heisenberg model. Based on the scaling equation and the critical exponents, the H − T phase diagram in the vicinity of the phase transition is constructed, where two critical points are determined.One is a tricritical point which locates at the intersection between the CSL, forced ferromagnetic (FFM), and paramagnetic (PM) states. The other one is a critical point situated at the boundaries between CSL, helimagnetic (HM), and PM states. I. INTRODUCTIONMagnetic materials with chirality have attracted considerable attention due to spintextures such as helimagnetic (HM) structure, conical magnetic ordering, magnetic skyrmion, chiral bobber [1][2][3][4][5]. The chirality with spin-orbital coupling in the crystal structure results in an antisymmetric exchange interaction called the Dzyaloshinskii-Moriya (DM) interaction, which is 1∼2 orders of magnitude weaker than the ferromagnetic coupling [6,7].The competition between the DM interaction with the ferromagnetic coupling causes the appearance of chiral spin-texture [8]. When an external magnetic field is applied above a threshold value, the HM ordering is usually modulated into particle-like spin-texture such as skyrmion, magnetic soliton.Recently, the monoaxial chiral magnet Cr 1/3 NbS 2 becomes prominent due to the chiral magnetic soliton lattice (CSL), which is a type of superlattice structure consist of periodic helical spin texture [9][10][11]. The crystal structure for Cr 1/3 NbS 2 belongs to the space group P 6 3 22 [12,13]. The hexagonal layers in 2H-NbS 2 are intercalated by the Cr ions which are in the trivalent state with localized moments S = 3/2, whereas the electronic conduction originates from an unfilled band of Nb atoms. Due to the strong magnetocrystalline anisotropy and DM interaction, Cr 1/3 NbS 2 displays a ground state of helical magnetic ordering with vector along the c-axis [13,14]. The magnetic sate can be modulated differently through the direction of the applied external field. When H is applied parallel to the c-axis, the HM ordering is polarized to conical ordering, and finally to forced ferromagnetical (FFM) phase. However, when H is applied perpendicularly to the c-axis, the HM structure with 48 nm changes continuously into CSL state, which is well reproduced by the one-dimensional chiral sine-Gordon model [10]. Further increase of H results in a phase transition from an incommensurate CSL to a commensurate FFM state [15]. It has been demonstrated that CSL can be effectively manipulated by magnetic field or current injection, which supplies potential ap...

The chiral helimagnet Cr 1/3 NbS 2 hosts exotic spin textures, whose influence on the magnetotransport properties make this material an ideal candidate for future spintronic applications. To date, the interplay between macroscopic magnetic and transport degrees of freedom is believed to result from a reduction in carrier scattering following spin order. Here, we present electronic structure measurements across the helimagnetic transition temperature T C that challenges this view. We show that the Fermi surface is comprised of strongly hybridized Nband Cr-derived electronic states, and that spectral weight close to the Fermi level increases anomalously as the temperature is lowered below T C. These findings are rationalized on the basis of first principle density functional theory calculations, which reveal a large nearestneighbor exchange energy, suggesting the interaction between local spin moments and hybridized Nb-and Cr-derived itinerant states to go beyond the perturbative interaction of Ruderman-Kittel-Kasuya-Yosida, suggesting instead a mechanism rooted in a Hund's exchange interaction.

We combine Raman scattering spectroscopy and lattice dynamics calculations to reveal the fundamental excitations of the intercalated metal monolayers in the Fe x TaS 2 (x = 1/4, 1/3) family of materials. Both in-and out-of-plane modes are identified, each of which has trends that depend upon the metal−metal distance, the size of the van der Waals gap, and the metal-to-chalcogenide slab mass ratio. We test these trends against the response of similar systems, including Crintercalated NbS 2 and RbFe(SO 4 ) 2 , and demonstrate that the metal monolayer excitations are both coherent and tunable. We discuss the consequences of intercalated metal monolayer excitations for material properties and developing applications.