Roy AS, Hoekstra AFT, Rosenbaum TF, Griessen R. Quantum fluctuations and the closing of the Coulomb gap in a correlated insulator.
Phys Rev Lett 2002;
89:276402. [PMID:
12513227 DOI:
10.1103/physrevlett.89.276402]
[Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2002] [Indexed: 05/24/2023]
Abstract
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 znu=6.0+/-0.5, where nu and z are the static and dynamical critical exponents, respectively.
Collapse