NUM division - Featured Research
Finite-temperature critical points and quantum critical end point in a 2D magnet
The Mermin–Wagner theorem has long told us that in two dimensions a continuous symmetry can be broken, allowing a finite order parameter, only at zero temperature. Now PSI theorist Bruce Normand, working with colleagues in Aachen, Amsterdam, Lausanne and Paris, has circumvented this rule. The team was considering the thermodynamics
Quantum magnets under pressure
The demonstration that applied pressure can substantially change – rather than merely tweak – the properties of a metal–organic quantum magnet indicates a route to designing quantum materials with tailored properties.
Multiferroics turned upside down
Experiments demonstrating the inversion of entire domain patterns in multiferroic crystals highlight just how versatile this class of materials is, and indicate a route to exploring novel functionalities.
Imaging the inside of injection needles with neutrons
Researchers from the Paul Scherrer Institute PSI, the University of Basel and Roche have used neutron imaging to investigate why cool storage is crucial for syringes pre-filled with a liquid medication.
A theory for the gapless field-induced quantum spin-liquid phase of α−RuCl3
The material α−RuCl3 continues to garner attention as the current poster child for realising the Kitaev model. New work places recent experimental observations on a solid theoretical footing, and concludes that the physics of α−RuCl3 is not dominated by Kitaev interactions.
Spin ice goes quantum
Numerous intriguing behaviours have been observed already in magnetic materials known as spin ices. But now for the first time direct manifestations of quantum mechanical effects have been seen in such a system.
The field-induced quantum spin-liquid phase of α−RuCl3 is gapless
Throughout 2017, the material α−RuCl3 has continued to inspire and fascinate those interested in correlated condensed matter. New experimental data now provide unique insight, and pose fresh challenges.
A null result full of insights
A laboratory-based search for axion dark matter ended, not unexpectedly, without a discovery. It provides, however, valuable constraints for the properties that these hypothetical particles can have — and thus a guide to where to look next.
Magnetic structures take a new turn
The unexpected finding that in an ‘artificial spin ice’ magnetostatic energy can be transformed into directed rotation of magnetization provides fresh insights into such nano-patterned magnetic structures — and might enable novel applications in nanoscale devices.