We propose four different mechanisms responsible for the paramagnetic or diamagnetic persistent currents in normal metal rings and determine the circumstances for changes of the current from paramagnetic to diamagnetic and vice versa. This might qualitatively reproduce the experimental results of Bluhm et al (2009 Phys. Rev. Lett. 102 136802).

There are not so many examples of real magnetic structures connected with living beings. Nanoparticles composed of magnetic iron oxides have been found in magnetotactic bacteria, some animals and plants. However, majority of structures found in living organisms are diamagnetic. Magnetic techniques used in biosciences and biotechnology are thus predominantly based on magnetic labelling of otherw...

The dynamics of the liquid crystal director in “near magic angle” sample spinning has been investigated in mesophases with positive and negative diamagnetic susceptibility anisotropies and their mixtures with near-zero macroscopic diamagnetic anisotropy. To this end the deuteron quadrupolar splitting of deuterochloroform dissolved in liquid crystals has been monitored. In systems with weakly po...

We show that a stable spontaneous current appears in a system of a spin density wave order with merons, vortices in the spin configuration with winding number +1. A meron in the spin density wave order modifies the boundary condition for eigenfunctions around it to a sign-change one. As a consequence, two types of stable current states, one with a clockwise circulation and the other with a coun...

The vanadium-vanadium interactions in the polygonal aggregates of d¹ vanadium(IV) atoms, with a total of 4k + 2 vanadium electrons (k an integer) imbedded in an electronically inactive borate matrix in certain vanadoborate structures are analogous to the ring carbon-carbon interactions in diamagnetic planar cyclic hydrocarbons. They thus represent a high-spin analogue of aromaticity. Thus, the ...

We have investigated the role of turbulence for two problems, the effect of the polarization current on the NTM and the effect of diamagnetic drifts on mode penetration. For the NTM problem, we find that the fluctuations exert a drag force on the island that results in a stabilizing slowdown in the propagation velocity. For the mode penetration problem, we have investigated the influence of pol...