Superconductivity and the fractional quantum Hall (FQH) effect are two landmark discoveries in modern physics. Superconductivity requires the presence of an effective pairing glue, which seems incompatible with the FQH effect, which requires strong repulsive interactions among electrons. Nevertheless, experiments in two-dimensional materials have recently observed both phases in close proximity to each other. A tantalizing explanation for this interplay is Laughlin's idea of “anyon superconductivity”, which proposes that superconductivity arises from a finite density of anyons — exotic quasiparticles emerging from the FQH state — carrying fractional charge. However, a key question is how Cooper pairing can occur in systems with purely repulsive interactions. I will demonstrate that anyon superconductivity can naturally emerge from an unconventional energy hierarchy of excitations when a missing ingredient is supplied: proximity to a topological phase transition. This provides a microscopic mechanism for anyon superconductivity, and allows us to construct the first controlled model for which low-energy Cooper pairs coexist with a FQH phase. I will present analytical and numerical results which could help guide future experiments and also allow us to describe continuous transitions between FQH states and chiral superconductors.
The plasma composition in the solar corona is variable, with a strong dependency on the first ionisation potential (FIP) of elements. In flaring regions, plasma composition has been shown to have significant spatial and temporal variations, likely driven by dynamical processes triggered by energy release at the reconnection site. The origin of these variations and their impact on flare loop dynamics are not yet fully understood. In this work, we use high cadence Hinode EIS spectroscopic observations of the M-class flare peaking at 13:56 UT on 2 April 2022, alongside simulations from the 0D EBTEL hydrodynamic model, to investigate the role of plasma composition in modulating radiative losses in solar flare loops. We identify two regions along the flare loop arcade, with distinct FIP bias values as well as cooling rates, suggesting that spatial variations in plasma composition may play a key role in influencing flare loop cooling. In this framework, I will also discuss the potential of high resolution spectropolarimetric observations from the upcoming IBIS 2.0 instrument, currently under installation at the THEMIS telescope, particularly for advancing studies of the physical mechanisms driving plasma composition variations, flare dynamics and the coupling between the two.
The colour–magnitude diagrams (CMDs) of star clusters underpin stellar astrophysics. They calibrate stellar evolution models, enable age-dating of stellar populations, and provide templates for interpreting unresolved galaxies. Yet the CMDs of young massive clusters show surprising features, such as split main sequences and extended turn-offs. This raises the question of whether we truly understand the mechanisms governing stellar distributions across the CMD.
In this talk, I will show how binary interactions and stellar rotation reshape CMD morphologies. Using observations of young massive clusters in the Magellanic Clouds obtained with HST and MUSE, we measure the spin velocities of large stellar samples and characterise the clusters’ binary populations. Our results reveal distinct populations of slow and fast rotators occupying different loci in the CMD. The detection of post-interaction binaries, such as blue stragglers and stripped stars, further enables us to constrain population synthesis models and to assess the contribution of massive star clusters to the cosmic rate of compact binary mergers observed via gravitational waves.
Um Zukunftsmusik geht es im Vortrag: Mission Vigil - Weltraumwettervorhersage aus einzigartiger Perspektive. 2031 startet die ESA-Raumsonde Vigil ins All. Aus seitlicher Beobachtungsposition wird der Sonnenspäher eher als erdnahe und erdgebundene Teleskope erkennen können, wenn sich auf der Sonne gefährliches Weltraumwetter zusammenbraut. Eines der wissenschaftlichen Instrumente der Mission entsteht derzeit am MPS. Johann Hirzberger vom MPS gibt einen Überblick.
