A Cryogenic Current Comparator is a highly sensitive tool for the non-destructive online monitoring of continuous as well as bunched beams of very low intensities. The noise-limited current resolution of such a device depends on the ferromagnetic material embedded in the pickup coil of the CCC. Therefore, the main focus of research was on the low temperature properties of ferromagnetic core mat...

The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane...

We propose a concrete model which exhibits ferromagnetism and electron-pair condensation simultaneously. The model is defined on two chains and consists of the electron hopping term, the on-site Coulomb repulsion, and a ferromagnetic interaction which describes ferromagnetic coupling between two electrons, one on a bond in a chain and the other on a site in the other chain. It is rigorously sho...

The magnetic polarization of a Pt capping layer leads to an increase of the interisland magnetic coupling in a two-dimensional array of Fe islands. For small superparamagnetic islands, Pt deposition leads to a superparamagnetic–ferromagnetic transition. For larger ferromagnetic but weakly coupled islands, Pt deposition produces a stronger interisland coupling. Polar Kerr spectroscopy measuremen...

We study the approximability of computing the partition function for ferromagnetic two-state spin systems. The remarkable algorithm by Jerrum and Sinclair showed that there is a fully polynomial-time randomized approximation scheme (FPRAS) for the special ferromagnetic Ising model with any given uniform external field. Later, Goldberg and Jerrum proved that it is #BIS-hard for Ising model if we...

In this work, a facile and versatile solution route was used to fabricate room-temperature ferromagnetic fish bone-like, pteridophyte-like, poplar flower-like, cotton-like Cu@Cu2O architectures and golfball-like Cu@ZnO architecture. The ferromagnetic origins in these architectures were found to be around metal-semiconductor interfaces and defects, and the root cause for their ferromagnetism lay...

Cuprate La-R 4Ba2Cu2O10 shows ferromagnetic to antiferromagnetic phase transition by replacing La ions with rare earth R=Nd, Sm, Eu, and Gd ions at low temperature. We propose that the transition is caused by a competition between antiferromagnetic superexchange interaction of Cu spins via La ions and ferromagnetic superexchange interaction due to Hund’s rule coupling of spins of holes on oxyge...

This paper describes the recognition of micro non-magnetic (conductive) and ferromagnetic material with spinvalve magneto-resistance (SV-GMR) sensor. High frequency and static magnetic fields were applied to material for the recognition of the micro conductive and ferromagnetic material respectively. The SV-GMR sensor is used to detect the magnetic field variation occurred wherever the material...

We used ferromagnetic artificial pinning centers in superconducting NbTi wires to achieve a large critical current density (Jc) in a magnetic field. Four wires were fabricated that contained nanometer-sized arrays of Ni or Fe pins inside micron-sized filaments of Nb0.36Ti0.64 alloy. A ferromagnetic pin volume of only 2% Ni produced Jc’s ~e.g., 2500 A/mm 2 at 5 T, 4.2 K! that were comparable to ...

We present a scattering treatment of transport in S-F-S junctions with a small ferromagnetic metal region inside the junction. The charge carriers are assumed not to thermalize with the fer-romagnet conduction band, and the ferromagnetic and superconductor orders coexist close to the interfaces. This requires a small ferromagnetic region in the junction. Ferromagnetism in the junction provides ...