A spin-wave analysis is developed to calculate the energies of the localized excitations occurring in two-dimensional ferromagnetic van der Waals monolayers when a substitutional magnetic impurity is introduced. The magnetic ions lie on a bipartite honeycomb lattice (similar to that for graphene) and the theory includes the effects of both Ising anisotropy and single-ion anisotropy to stabilize the magnetic ordering perpendicular to the atomic plane at low temperatures. A Dyson-equation formalism, together with the spin-dependent Green's functions derived for van der Waals monolayers, is employed to evaluate the existence conditions and energies for the impurity modes, which lie above the band of spin-wave states of the pure host material. For realistic parameter values it is found that typically two impurity modes may exist, depending on the spin quantum number for the magnetic impurity atom. Numerical applications are made to CrIand CrGeTeas the host materials.
The absence of intrinsic magnetism in two-dimensional (2D) materials demands functionalization as necessary for broadening their applications. In this work, doping with transition metals (Mn and Fe) is proposed to modify the electronic and magnetic properties of a GeS monolayer. A pristine monolayer is an indirect gap semiconductor with an energy gap of 0.
This study demonstrated the impact of formic acid (FAc), a common reactive impurity in pharmaceutical excipients, on the stability of mirabegron (MB). The investigation of MB-excipient compatibility tests revealed the formation of a new degradation product, FAc-DP, at 0.2% after 7 days of isothermal stress at 55°C.
RMn6Sn6 (R = rare-earth) kagome magnets have been one of the research focuses in condensed matter physics, primarily due to their exotic physical properties rooted in the interplay between magnetism and nontrivial topological band structures. We reported herein the crystal growth of Cr substituted DyMn4Cr2Sn6 and investigations on their magnetotransport properties. It is unveiled that the Mn kagome layer is destroyed and the in-plane ferromagnetic exchange is consequently weakened by the substituted nonmagnetic Cr.
Optically accessible spin-active nanomaterials are promising as quantum nanosensors for probing biological samples. However, achieving bioimaging-level brightness and high-quality spin properties for these materials is challenging and hinders their application in quantum biosensing. Here, we demonstrate bright fluorescent nanodiamonds (NDs) containing 0.
Background: Moxidectin is an active pharmaceutical ingredient (API) extensively used in various drug products within the pharmaceutical and animal health sectors. Despite its widespread use, the analytical methods prescribed by the United States Pharmacopeia (USP) and European Pharmacopoeia (EP, Ph. Eur.
