Domain Wall Patterning and Giant Response Functions in Ferrimagnetic Spinels.

The manipulation of mesoscale domain wall phenomena has emerged as a powerful strategy for designing ferroelectric responses in functional devices, but its full potential is not yet realized in the field of magnetism. This work shows a direct connection between magnetic response functions in mechanically strained samples of Mn O and MnV O and stripe-like patternings of the bulk magnetization which appear below known magnetostructural transitions. Building off previous magnetic force microscopy data, a small-angle neutron scattering is used to show that these patterns represent distinctive magnetic phenomena which extend throughout the bulk of two separate materials, and further are controllable via applied magnetic field and mechanical stress.

Asymmetric Fraunhofer spectra in a topological insulator-based Josephson junction.

Josephson junctions with topological insulators as their weak link (S-TI-S junctions) are predicted to host Majorana fermions, which are key to creating qubits for topologically protected quantum computing. But the details of the S-TI-S current-phase relation and its interplay with magnetic fields are not well understood. We fabricate a BiSejunction with NbTi leads and measure the Fraunhofer patterns of the junction with applied in-plane fields.

Finite momentum Cooper pairing in three-dimensional topological insulator Josephson junctions.

Unconventional superconductivity arising from the interplay between strong spin-orbit coupling and magnetism is an intensive area of research. One form of unconventional superconductivity arises when Cooper pairs subjected to a magnetic exchange coupling acquire a finite momentum. Here, we report on a signature of finite momentum Cooper pairing in the three-dimensional topological insulator BiSe.

A simple chemical vapor deposition method for the production of highly conductive polymer poly(3,4-ethylenedioxythiophene).

Conductive thin films of Poly(3,4-ethylenedioxythiophene) (PEDOT) have been successfully deposited on a variety of substrates by a simple chemical vapor deposition (CVD) method starting from the liquid monomer (EDOT) and using FeCl3 as a catalyst. Resistivity measurements indicated very good conductivity of the material, comparable with other previously reported values for PEDOT deposited by CVD. Further cyclic voltammetry measurements indicated a value of around -4.