相关论文: Spin stiffness and quantum fluctuations in C-type …

We have developed a consistent theory of the Heisenberg quantum antiferromagnet in the disordered phase with a short range antiferromagnetic order on the basis of the path integral for spin coherent states. We have presented the Lagrangian…

We report the signatures of dynamic spin fluctuations in the layered honeycomb Li$_3$Cu$_2$SbO$_6$ compound, with a 3$d$ S = 1/2 $d^9$ Cu$^{2+}$ configuration, through muon spin rotation and relaxation ($\mu$SR) and neutron scattering…

The proximity effect of a C-type antiferromagnet (C-AFM) with the spin canting at low temperature is investigated in the hybrid Nd0.35Sr0.65MnO3(NSCO)/YBa2Cu3O7(YBCO) oxide system through magnetic and transport measurements. It is found…

Spin fluctuations were studied over a wide momentum ($\hbar Q$) and energy ($E$) space in the frustrated $d$-electron heavy-fermion metal LiV$_2$O$_4$ by time-of-flight inelastic neutron scattering. We observed the overall $Q$$-$$E$…

We report the magnetic and calorimetric measurements in single crystal samples of the square lattice $J_{1}-J_{2}$ quantum antiferromagnet BaCdVO(PO$_4$)$_2$. An investigation of the scaling of magnetization reveals a "dimensionality…

We develop an approach to describe antiferromagnetic magnons on a bipartite lattice supporting the N\'{e}el state using fractionalized degrees of freedom typically inherent to quantum spin liquids. In particular we consider a long-range…

We consider the effect of thermal fluctuations on rotating spinor F=1 condensates in axially-symmetric vortex phases, when all the three hyperfine states are populated. We show that the relative phase among different components of the order…

We derive a master equation that allows us to study non-equilibrium dynamics of a quantum antiferromagnet. By resorting to spin-wave theory, we obtain a closed analytic form for the magnon decay rates. These turn out to be closely related…

We report a neutron diffraction and muon spin relaxation muSR study of static and dynamical magnetic properties of BaCo2V2O8, a quasi-one-dimensional spin-chain system. A proposed model for the antiferromagnetic structure includes: a…

In this paper, we revisit the antiferromagnetic (AF) phase diagram of the single-band three-dimensional half-filled Hubbard model on a simple cubic lattice studied within the dynamical mean field theory (DMFT). Although this problem has…

In La1.48Nd0.4Sr0.12CuO4 the 139La and 63Cu NQR relaxation rates and signal wipe-out upon lowering temperature are shown to be due to purely magnetic fluctuations. They follow the same renormalized classical behavior as seen in neutron…

We study a localized spin coupled to an Anderson impurity to model the situation found in higher transition metal or rare earth compounds like e.g.\ LaMnO$_3$ or Gd monopnictides. We find that, even for large quantum numbers of the…

We present the ground state properties of a new quantum antiferromagnet YbBO$_3$ in which the isotropic Yb$^{3+}$ triangular layers are separated by a non-magnetic layer of partially occupied B and O(2) sites. The magnetization and heat…

We investigate the wavepacket spreading after a single spin flip in prototypical two-dimensional ferromagnetic and antiferromagnetic quantum spin systems. We find characteristic spatial magnon density profiles: While the ferromagnet shows a…

The spin waves in the multi-k antiferromagnet, USb, soften and become quasielastic well below the AFM ordering temperature, T_N. This occurs without a magnetic or structural transition. It has been suggested that this change is in fact due…

We present a SU(2) gauge theory of fluctuating magnetic order in the two-dimensional Hubbard model. The theory is based on a fractionalization of electrons in fermionic chargons and bosonic spinons. The chargons undergo N\'eel or spiral…

In general, quantum fluctuations are suppressed in ferromagnetic materials because they admit a simple unfrustrated ground state, greatly limiting the scope of phenomena that can be observed in these materials. In this work, we show how…

The magnetic structure of (La${}_{1.8}$Eu${}_{0.2}$)CuO${}_4$ has been studied by magnetization measurements of single crystals, which show antiferromagnetic long-range order below $T_N$ = 265 K and a structural phase transition at $T_s$ =…

Magnetic excitations in the spin-$\frac{1}{2}$ distorted kagome lattice antiferromagnet Cs$_2$Cu$_3$SnF$_{12}$, which has an ordered ground state owing to the strong Dzyaloshinskii-Moriya interaction, were studied using inelastic neutron…

The relation between three-dimensional lattice structure and magnetism in correlated electron systems is explored for face centered cubic (FCC), body centered cubic (BCC), and simple cubic (SC) lattices. In particular, we question which…