Charge ordering of magnetic monopoles in triangular spin ice patterns

Artificial spin ice offers the possibility to investigate a variety of dipolar orderings, spin frustrations and ground states. However, the most fascinating aspect is the realization that magnetic charge order can be established without spin order. We have investigated magnetic dipoles arranged on a honeycomb lattice as a function of applied field, using magnetic force microscopy. For the easy direction with the field parallel to one of the three dipole sublattices we observe at coercivity a maximum of spin frustration and simultaneously a maximum of charge order of magnetic monopoles with alternating charges $\pm$ 3.Comment: 7 pages, 4 figure

Malvina, or Spoken and Written Word in the Novel

This study by Szary-Matywiecka presents Malvína, or the Heart’s Intuition by Maria Wirtemberska, the first Polish psychological novel, as a work worth of critical attention. Despite its didactic message about the superiority of the heart over the mind, the work met with early success. The study deals with several aspects of the novel, while making use of methods developed by structuralists and formalists, including Michał Głowiński’s concept of formal mimesis. At the same time, it relies on current theories on language and proves that Malvína is not merely a sentimental book. The novel makes use of the traditional motif of twins separated at birth who finally meet many years later, and captures a picture of society of that time in Warsaw. The plot is permeated by the theme of doubling, two main male characters, double literary energy, and the double self of Wirtemberska as both the narrator and author.Publishe

Single pulse modeling and the bi-drifting subpulses of radio pulsar B1839-04

We study the bi-drifting pulsar B1839-04, where the observed subpulse drift direction in the two leading pulse components is opposite from that in the two trailing components. Such diametrically opposed apparent motions challenge our understanding of an underlying structure. We find that for the geometry spanned by the observer and the pulsar magnetic and rotation axes, the observed bi-drifting in B1839-04 can be reproduced assuming a non-dipolar configuration of the surface magnetic field. Acceptable solutions are found to either have relatively weak $(\sim 10^{12} \,{\rm G})$ or strong $(\sim 10^{14} \,{\rm G})$ surface magnetic fields. Our single pulse modeling shows that a global electric potential variation at the polar cap that leads to a solid-body-like rotation of spark forming regions is favorable in reproducing the observed drift characteristics. This variation of the potential additionally ensures that the variability is identical in all pulse components resulting in the observed phase locking of subpulses. Thorough and more general studies of pulsar geometry show that a low ratio of impact factor to opening angle $(\beta / \rho)$ increases the likelihood of bi-drifting to be observed. We thus conclude that bi-drifting is visible when our line of sight crosses close to the magnetic pole.Comment: 15 pages, 14 figures, accepted for publication in Ap