Related papers: Intrinsic and extrinsic nonstationary field-driven…
The parametric excitation of spin waves by coherent surface acoustic waves is demonstrated experimentally in metallic magnetic thin film structures. The involved magnon modes are analyzed with micro-focused Brillouin light scattering…
Quantum dots are recognized as a suitable platform for studying thermodynamic phenomena involving single electronic charges and spins in nano-scale devices. However, such a thermodynamic system is usually driven by electron reservoirs at…
We develop a technique to compute the high-frequency asymptotics of spin correlators in weakly interacting disordered spin systems. We show that the dynamical spin correlator decreases exponentially at high frequencies, $<…
The very low temperature properties of two pyrochlore compounds, Yb2Ti2O7 and Gd2Sn2O7, were investigated using an ensemble of microscopic and bulk techniques. In both compounds, a first order transition is evidenced, as well as spin…
We report muon spin relaxation and inelastic neutron measurements on the Heusler system YbPd$_2$Sn. Localised anisotropic and quasi-elastic Yb magnetic fluctuations are observed below $T = 150$K. Both $\mu$SR and neutron data indicate a…
We study the flow of a spinor (F=1) Bose-Einstein condensate in the presence of an obstacle. We consider the cases of ferromagnetic and polar spin-dependent interactions and find that the system demonstrates two speeds of sound that are…
The low-dimensional s=1/2 compound (NO)[Cu(NO3)3] has recently been suggested to follow the Nersesyan-Tsvelik model of coupled spin chains. Such a system shows unbound spinon excitations and a resonating valence bond ground state due spin…
We combine two aspects of magnetic frustration, multiferroicity and emergent quasi-particles in spin liquids, by studying magneto-electric monopoles. Spin ice offers to couple these emergent topological defects to external fields, and to…
We present a comprehensive study of polar and magnetic excitations in BiFeO3 ceramics and a thin film epitaxially grown on an orthorhombic (110) TbScO3 substrate. Infrared reflectivity spectroscopy was performed at temperatures from 5 to…
An analysis is presented of the behaviour of muons in the low-temperature state in spin ice. It is shown in detail how the behavior observed in some previous muon experiments on spin ice in a weak transverse field may result from the…
The description and detection of unconventional magnetic states such as spin liquids is a recurring topic in condensed matter physics. While much of the efforts have traditionally been directed at geometrically frustrated antiferromagnets,…
Zero-field muon-spin relaxation measurements of the frustrated triangular quantum magnet AgNiO2 are consistent with a model of charge disproportionation that has been advanced to explain the structural and magnetic properties of this…
Quantum spin liquids are exotic phases of matter that are prevented from being frozen even at zero temperature, and appear disordered by local probes that monitor the subsystems. Driven by quantum fluctuations, topological spin liquids are…
Increasing the spin coherence time (T2) is a major area of interest for spin defect systems such as the silicon (V$_Si$) and carbon (V$^\pm _C$) vacancies in 4H-SiC. Usually as temperature increases, T2 decreases due to the thermal bath.…
There is a long-time quest for understanding physical mechanisms of weak magnetic field interaction with biological matter. Two factors impeded the development of such mechanisms: first, a high (room) temperature of a cellular environment,…
Spin fluctuations are reported near the magnetic field driven quantum critical point in YbRh2Si2. On cooling, ferromagnetic fluctuations evolve into incommensurate correlations located at q0=+/- (delta,delta) with delta=0.14 +/- 0.04 r.l.u.…
We study the decoherence of a spin-1/2 induced by an environment which is on the verge of a continuous phase transition. We consider spin environments described by the ferromagnetic and antiferromagnetic Heisenberg models on a square…
Counterintuitive order-disorder phenomena emerging in antiferromagnetically coupled spin systems have been reported in various studies. Here we perform a systematic effective field theory analysis of two-dimensional bipartite quantum…
The phonon dispersion was measured at room temperature along (0,0,L) in the tetragonal phase of LaFeAsO using inelastic x-ray scattering. Spin-polarized first-principles calculations imposing various types of antiferromagnetic order are in…
Muon spin rotation and relaxation experiments in the pyrochlore iridate Eu2Ir2O7 yield a well-defined muon spin precession frequency below the metal-insulator/antiferromagnetic transition temperature TM = 120 K, indicative of long-range…