相关论文: Spin stiffness and quantum fluctuations in C-type …
The spin dynamics and electronic orders of the kagome system at different filling levels stand as an intriguing subject in condensed matter physics. By first-principles calculations and random phase approximation analyses, we investigate…
Recently, orthorhombic CuMnAs has been proposed to be a magnetic material where topological fermions exist around the Fermi level. Here we report the magnetic structure of the orthorhombic Cu0.95MnAs and Cu0.98Mn0.96As single crystals.…
We present the full analysis of the normal state of the spin-fermion model near the antiferromagnetic instability in two dimensions. This model describes low-energy fermions interacting with their own collective spin fluctuations, which…
We report on 31P-NMR studies of LaFe(As_{1-x}P_x)(O_{1-y}F_{y}) over wide compositions for 0<x<1 and 0<y<0.14, which provide clear evidence that antiferromagnetic spin fluctuations (AFMSFs) are one of the indispensable elements for…
Resistance fluctuation phenomenon in antidot lattices in the quantum Hall regime are studied. Magnetoresistance of finite antidot array systems in the quantum Hall plateau transition regime exhibits two types of oscillatory effect. One is…
Novel magnetic phases are expected to occur in highly frustrated spin systems. Here we study the structurally perfect kagom\'e antiferromagnet CdCu$_3$(OH)$_6$(NO$_3$)$_2\cdot$H$_2$O by magnetization, magnetic torque, and heat capacity…
Spin-phonon coupling effects, as reflected in phonon frequency shifts between ferromagnetic (FM) and G-type antiferromagnetic (AFM) configurations in cubic CaMnO$_3$, SrMnO$_3$, BaMnO$_3$, LaCrO$_3$, LaFeO$_3$ and La$_2$(CrFe)O$_6$, are…
Starting from the $CP^{N-1}$ model description of the thermally disordred phase of the $D=2$ quantum antiferromagnet, we examine the interaction of the Schwinger-boson spin-1/2 mean-field excitations with the generated gauge (chirality)…
Measurements of the static magnetization, susceptibility and ESR of Gd spin probes have been performed to study the properties of antiferromagnetically ordered La_{2-x-y}Eu_ySr_xCuO_4 (x less or equal 0.02) with the low temperature…
We report the analysis of the magnetic fluctuations in the superconducing La_{2-x}Sr_xCuO_4 and the related lanthanum cuprates having the different symmetry of the low temperature structure. The NMR and ESR investigations revealed the…
We study the properties of generalized striped phases of doped cuprate planar quantum antiferromagnets. We invoke an effective, spatially anisotropic, non-linear sigma model in two space dimensions. Our theoretical predictions are in…
We present a comprehensive study of synthesis, structure analysis, transport and thermodynamic properties of the C14 Laves phase Ta(Fe1-xVx)2. Our measurements confirm the appearance of spin-density wave (SDW) order within a dome-like…
We review ground states and excitations of a quantum antiferromagnet on triangular and other frustrated lattices. We pay special attention to the combined effects of magnetic field h, spatial anisotropy R, and spin magnitude S. The focus of…
We report magnetic susceptibility, specific heat and muon spin relaxation (muSR) experiments on the triangular antiferromagnet La2Ca2MnO7 which develops a genuine two-dimensional, three-sublattice \sqrt{3} \times \sqrt{3} magnetic order…
We investigate the frustrated magnetic interactions in cubic transition metal oxides with orbital degeneracy. The $e_g$ orbitals order easier and their ordering explains the $A$-type antiferromagnetic phase in KCuF$_3$ and LaMnO$_3$. In…
We report a systematic study by 75As nuclear-quadrupole resonance in LaFeAsO1-xFx. The antiferromagnetic spin fluctuation (AFSF) found above the magnetic ordering temperature TN = 58 K for x = 0.03 persists in the regime 0.04 < x < 0.08…
An ongoing challenge in the study of quantum materials, is to reveal and explain collective quantum effects in spin systems where interactions between different modes types are important. Here we approach this problem through a combined…
We study the nearest-neighbor Heisenberg antiferromagnet on a face-centered cubic lattice with arbitrary spin S. The model exhibits degenerate classical ground states including two collinear structures AF1 and AF3 described by different…
Elastic and inelastic neutron scattering studies reveal details of the antiferromagnetic tansition and intriguing spin-dynamics in the magneto-electric effect single crystal LiMnPO$_4$. The elastic scattering studies confirm the system is…
Elastic and inelastic neutron scattering were used to study the ordered phase of the quasi-one-dimensional spin-1/2 antiferromagnet ${\rm BaCu_{2}Si_{2}O_{7}}$. The previously proposed model for the low-temperature magnetic structure was…