PHASE-TRANSITION-INDUCED CARRIERMASS ENHANCEMENT IN 2D RUDDLESDEN− POPPER PEROVSKITES
Michal Baranowski and Paulina Plochocka, LNCMI-Toulouse Organic-inorganic halide perovskites have become the “next big thing” in emerging semiconductor materials, with their unprecedented rapid development and successful application in high-performance photovoltaics. Yet, their inherent instabilities with respect to moisture remain [...]
NEGATIVE THERMAL EXPANSION IN A MAGNETICALLY FRUSTRATED SPINEL
Lisa Rossi and Ben Bryant, HFML Nijmegen Frustrated magnets are materials with competing spin interactions, which cannot be simultaneously satisfied. While these materials have become most famous as a playground for novel phases, such as quantum spin liquids, they [...]
CYCLOTRON EMISSION FROM MASSLESS KANE ELECTRONS
Milan Orlita, LNCMI-Grenoble. When a magnetic field is applied to a solid, the continuous density of electronic states transforms into a set of discrete energy levels, known as Landau levels. Electrons excited in such a ladder may recombine, with [...]
UNCOVERING THE MICROSCOPIC NATURE OF THE FIELD-INDUCED PHASE TRANSITION IN HoFe5Al7
Denis Gorbunov, HLD Dresden. Intermetallic compounds based on 3d and 4f elements combine high magnetic ordering temperatures, typical of 3d metals, and the large magnetic anisotropy of the magnetic rare-earths elements. The application of external magnetic fields tunes the [...]
MAGNETIC-FIELD-INDUCED METAMAGNETISM AND REENTRANT SUPERCONDUCTIVITY IN THE HEAVY-FERMION SUPERCONDUCTOR UTe2
William Knafo, Marc Nardone (LNCMI Toulouse), Sanu Mishra (LNCMI Grenoble) and Georg Knebel (CEA-Grenoble). Following the recent discovery of superconductivity in the heavy-fermion paramagnet UTe2, which is suspected to lie on the verge of ferromagnetism [S. Ran et al., [...]
ELECTRICAL RESISTIVITY ACROSS A NEMATIC QUANTUM CRITICAL POINT
Nigel Hussey, HFML Nijmegen. It is not only elemental or ordinary metals that superconduct. Today, scientists are also fascinated by strange metals that undergo phase transitions (e.g. to a magnetic state) before superconductivity sets in. If they find the [...]
BRAZILIAN PHD INTERNSHIPS AT HFML: SUCCESSFUL COLLABORATION
Steffen Wiedmann, HFML Nijmegen. In 2017 and 2018, two PhD students from Brazil came to Nijmegen to do a part of their post-graduate program at the EMFL facility in Nijmegen. They obtained a one-year PhD fellowship from the Federal Agency [...]
PRESSURE TUNING OF EXCHANGE COUPLINGS IN A FRUSTRATED MAGNET
Sergei Zvyagin, HLD Dresden. Spin-1/2 triangular-lattice Heisenberg antiferromagnets represent one of the most important classes of frustrated quantum magnets, demonstrating a complex interplay between geometrical frustration, quantum fluctuations, and magnetic order. In spite of their simple magnetic structures (Figure, [...]
PULSED-FIELD NMR STUDY OF CeIn3 UP TO 56 T
Yo Tokunaga, JAEA Tokai, Nicolas Bruyant, LNCMI-Toulouse, and Ilya Sheikin, LNCMI-Grenoble. Heavy-fermion materials exhibit a diverse range of fascinating phenomena including quantum phase transition (QPTs), non-Fermiliquid behavior, and novel states of matter such as unconventional superconductivity. The application of [...]
INSULATING STATES OF REPLICA DIRAC FERMIONS IN GRAPHENE SUPERLATTICES
Sergio Pezzini, Steffen Wiedmann, Uli Zeitler, HFML Nijmegen. Two-dimensional layers of graphene and hexagonal boron nitride (hBN) both have a honeycomb atomic structure, with a slight lattice mismatch of 1.8 %. When placing graphene on top of hBN one [...]