Magnetic monopoles have been proposed as emergent quasiparticles in pyrochlore spin ice compounds. However, unlike semiconductors and two-dimensional electron gases where the charge degree of freedom can be actively controlled by chemical doping, interface modulation, and electrostatic gating, there is as of yet no analogue of these effects for emergent magnetic monopoles. To date, all experimental investigations have been limited to large ensembles comprised of equal numbers of monopoles and antimonopoles in bulk crystals.

We present direct evidence for an enhanced superconducting Tc on the surface of cleaved single crystals of Ba(Fe 0.95 Co 0.05)2As2. Transport measurements performed on samples cleaved in ultra-high vacuum show a significantly enhanced superconducting transition when compared to equivalent measurements performed in air. Deviations from the bulk resistivity appear at 21 K, well above the 10 K bulk Tc of the underdoped compound.

We have studied the low temperature electrical transport properties of LaxSr1-xCuO2 thin films grown by oxide molecular beam epitaxy on (1 1 0) GdScO3 and TbScO3 substrates. The transmission electron microscopy measurements and the x-ray diffraction analysis confirmed the epitaxy of the obtained films and the study of their normal state transport properties, removing the ambiguity regarding the truly conducting layer, allowed to highlight the presence of a robust hidden Fermi liquid charge transport in the low temperature properties of infinite layer electron doped cuprate superconductors.

The synthesis of stoichiometric Sr2RuO4 thin films has been a challenge because of the high volatility of ruthenium oxide precursors, which gives rise to ruthenium vacancies in the films. Ru vacancies greatly affect the transport properties and electronic phase behavior of Sr2RuO4, but their direct detection is difficult due to their atomic dimensions and low concentration. We applied polarized X-ray absorption spectroscopy at the oxygen K edge and confocal Raman spectroscopy to Sr2RuO4 thin films synthesized under different conditions.

Recent research on photocathodes for photoinjectors has focused on the understanding of the photoemission process at low energy (i.e. at photon energy close to the material’s work function) as well as on the study of ordered and innovative photocathode materials, with the aim of minimizing the emittance at the cathode. We here present a preliminary study on low energy photoemission from (100) oriented Ba1−xLaxSnO3 thin films, characterizing their quantum efficiency and the mean transverse energy of the photoelectrons.

The interplay between strong spin-orbit coupling and electron correlations has recently been the subject of intense investigation, due to a number of theoretically predicted phases such as quantum spin liquids, unconventional superconductivity, complex magnetic orders, and correlated topological phases of matter. In particular, iridates have been proposed as a promising family of materials which could host a number of these phases.

SrCuO2/Sr0.9La0.1CuO2/SrCuO2 trilayers were grown by oxide-molecular beam epitaxy. The thicknesses of the top and bottom SrCuO2 layers were fixed, while the thickness of the infinite-layer electron-doped cuprate Sr0.9La0.1CuO2 central layer was systematically changed. Transmission electron microscopy, x-ray reflectivity and x-ray diffraction measurements were performed to assess the sample quality and the abruptness of the interfaces.

SnSe2 is a layered main-group metal dichalcogenide that has exhibited gate-tunable interfacial superconductivity as well as promising optoelectronic applications. Here, we synthesize SnSe2 films by molecular beam epitaxy and investigate their electronic structure with angle-resolved photoemission spectroscopy (ARPES). A comparison between density functional theory calculations and ARPES data from a thick film reveals the importance of spin-orbit coupling and out-of-plane dispersion in the SnSe2 valence bands, which were neglected in previous studies of its electronic structure.

The transition temperature T c of unconventional superconductivity is often tunable. For a monolayer of FeSe, for example, the sweet spot is uniquely bound to titanium-oxide substrates. By contrast for La 2−x Sr x CuO 4 thin films, such substrates are sub-optimal and the highest T c is instead obtained using LaSrAlO 4 . An outstanding challenge is thus to understand the optimal conditions for superconductivity in thin films: which microscopic parameters drive the change in T c and how can we tune them?