Materials Sciences and Engineering Research Highlights

Squeezed Nanocrystals

We have developed and validated a model which predicts size-independent shapes of metal nanoparticles that are supported on a solid surface and blanketed by a two-dimensional material such as graphene.

Manipulating Coherent Transport in Topologically Protected Surface States

Topology-protected charge transport on surfaces of three-dimensional topological insulators (TIs) is breaking new ground in quantum science and technology.

Ab Initio Simulation of DNP Enhancements

Accelerating the discovery of improved polarizing agents through simulation requires a proper treatment of the concerted dynamics of thousands of spins over several seconds, far exceeding conventional approaches incorporating only a handful of spins. This was achieved by restricted state space methods and a Monte Carlo optimization algorithm to calculate the enhancements directly, without worrying about the timescale of the interactions. This new approach enabled the calculation of DNP enhancements in systems containing upwards of 50 spins allowing for the importance of the spin diffusion and the diffusion barrier to be determined.

Simple stress criterion for navigating phase transformations

Lattice instability criterion is linear in stresses for any stress state in a material.

New Quantum Criticality Discovered in Superconductivity

Understanding the link between magnetism and unconventional superconductivity remains a grand challenge in quantum materials. Significant progress gaining deeper insight into this challenge has been made via the first observation of a quantum criticality (QC) with a hedgehog spin-vortex crystal antiferromagnetic state.

Rapid Characterization of Organolead Halide Perovskites

Organolead halide and mixed halide perovskites (CH3NH3PbX3, CH3NH3PbX3–nYn, X and Y = Cl–, Br–or I–), are promising materials for photovoltaics and optoelectronic devices but phase segregation halide ion speciation in mixed halide perovskites remain a challenge. Here we show that both fast MAS and DNP-enhanced solid-state NMR spectroscopy can increase sensitivity while reducing data acquisition time.