Quantum Fluctuations and the Closing of the Coulomb Gap in a Correlated Insulator

The “switchable mirror” yttrium hydride is one of the few strongly correlated systems with a continuous Mott-Hubbard metal-insulator transition. We systematically map out the low temperature electrical transport from deep in the insulator to the quantum critical point using persistent photoconductivity as a drive parameter. Both activated hopping over a Coulomb gap and power-law quantum fluctuations must be included to describe the data. Collapse of the data onto a universal curve within a dynamical scaling framework (with corrections) requires zν=6.0±0.5, where ν and z are the static and dynamical critical exponents, respectively

Нелинейная нетерова краевая задача в критическом случае

Знайдено необхiднi та достатнi умови iснування розв’язкiв слабко нелiнiйної нетерової крайової задачi для системи звичайних диференцiальних рiвнянь у критичному випадку.We construct necessary and sufficient conditions for the existence of the solution of a Noether weakly nonlinear boundary-value problem for a system of ordinary differential equations in the critical case