相关论文: Direct imaging of a Berry curvature nematic state …
Chiral magnetic textures, such as skyrmions, are of great interest to the condensed matter community due to their novel transport properties. The stabilization of topologically non-trivial magnetic phases, like the skyrmion lattice in MnSi,…
The anomalous Hall effect in ferromagnetic metals is classified into two based on the mechanism. The first one is the intrinsic Hall effect due to the Berry curvature in momentum space; this is a Hall effect that solely arises from the band…
The Berry curvature is a geometrical property of an energy band which acts as a momentum space magnetic field in the effective Hamiltonian describing single-particle quantum dynamics. We show how this perspective may be exploited to study…
We study nonlinear magneto-optical responses of metals by a semiclassical Boltzmann equation approach. We derive general formulas for linear and second order nonlinear optical effects in the presence of magnetic fields that include both…
Femtosecond laser excitation of materials that exhibit magnetic spin textures promises advanced magnetic control via the generation of ultrafast and non-equilibrium spin dynamics. We explore such possibilities in ferrimagnetic [Fe(0.35…
In Mott insulators the evolution of antiferromagnetic order to superconducting or charge-density-wave-like states upon chemical doping underpins the control of quantum phases. Photo-doping can induce similar transitions on the ultrafast…
Combining field-theoretical methods and ab-initio calculations, we construct an effective Hamiltonian with a single giant-spin degree of freedom, capable of the describing the low-energy spin dynamics of ferromagnetic metal nanoclusters…
Berry curvature multipoles appearing in topological quantum materials have recently attracted much attention. Their presence can manifest in novel phenomena, such as nonlinear anomalous Hall effects (NLAHE). The notion of Berry curvature…
Intertwining of different quantum degrees of freedom manifests exotic quantum phenomena in many-body systems, especially in reduced dimensionality. Here we show that monolayered NbTe2 serves as an ideal platform where lattice, charge, and…
We study the quantum nonlinear planar Hall effect in bilayer graphene under a steady in-plane magnetic field. When time-reversal symmetry is broken by the magnetic field, a charge current occurs in the second-order response to an external…
We present a formalism based on colour symmetry to analyse the momentum-space spin textures of non-collinear antiferromagnets. We show that, out of the spin textures allowed by the magnetic point group, \textcolor{\altcolor} {one can…
We study theoretically the destruction of spin nematic order due to quantum fluctuations in quasi-one dimensional spin-1 magnets. If the nematic ordering is disordered by condensing disclinations then quantum Berry phase effects induce…
In this work, we investigate collective electronic fluctuations and, in particular, the possibility of the charge density wave ordering in an infinite-layer NdNiO$_2$. We perform advanced many-body calculations for the ab-initio…
The recently introduced concept of "surface Berry plasmons" is studied in the concrete instance of a ferromagnetic conductor in which the Berry curvature, generated by spin-orbit (SO) interaction, has opposite signs for carriers parallel or…
Magnetic and ferroelectric properties of layered geometrically frustrated cluster compound FeTe$_2$O$_5$Br were investigated with single-crystal neutron diffraction and dielectric measurements. Incommensurate amplitude modulated magnetic…
We theoretically show that moderate interaction between electrons confined to move in a plane and localized magnetic moments leads to formation of a noncoplanar magnetic state. The state is similar to the skyrmion crystal recently observed…
We present the microscopic theory of improper multiferroicity in BiMnO3, which can be summarized as follows: (1) the ferroelectric polarization is driven by the hidden antiferromagnetic order in the otherwise centrosymmetric C2/c structure;…
We study an unique form of metallic ferromagnetism in which orbital moments surpasses the role of spin moments in shaping the overall magnetization. This system emerges naturally upon doping a topologically non-trivial Chern band in the…
The ability to controllably manipulate the laser-induced ultrafast magnetic dynamics is a prerequisite for future high speed spintronic devices. The optimization of devices requires the controllability of the ultrafast demagnetization time,…
Density-functional calculations are carried out to investigate incommensurate magnetic structures and ferroelectric polarization in newly discovered multiferroic material MnI$_2$. The exchange interactions among local moments on Mn are…