Pressure-driven 5f localized-itinerant transition and valence fluctuation in cubic phase californium

Pressure-driven insulator-metal transition in cubic phase UO2

Understanding the electronic properties of actinide oxides under pressure poses a great challenge for experimental and theoretical studies. Here, we investigate the electronic structure of cubic phase uranium dioxide at different volumes using a combination of density functional theory and dynamical mean-field theory. The ab initio calculations predict an orbital-selective insulator-metal trans...

Fluctuation-driven electroweak phase transition.

We examine the dynamics of the electroweak phase transition in the early Universe. For Higgs masses in the range 46 < MH < 150 GeV and top quark masses less than 200 GeV, regions of symmetric and asymmetric vacuum coexist to below the critical temperature, with thermal equilibrium between the two phases maintained by fluctuations oi both phases. We propose that the transition to the asymmetric ...

Pressure-driven Quantum Phase Transition

The zero-temperature quantum phase transition (QPT) is driven by quantum fluctuations, in contrast to the more familiar finite temperature transitions driven by thermal fluctuations. This paper demonstrates our work on two kinds of QPTs in two different materials, respectively. The first work focuses on the pressure-driven antiferromagnetic QPT in pure chromium which is a model system for study...

The localized-to-delocalized transition in mixed-valence chemistry.

Spin Excitations in Localized and Itinerant Magnets

Collective excitations in magnetic materials can be investigated by means of inelastic neutron scattering. We show that this experimental method gives access to the complete spectrum of magnetic fluctuations through the energyand momentum-dependence of the dynamical susceptibility. We focus on the dynamical properties of magnets with localized spin densities and of metals. From such studies, mi...