Loading…
Universality of Boundary Charge Fluctuations
We establish the quantum fluctuations ΔQ_{B}^{2} of the charge Q_{B} accumulated at the boundary of an insulator as an integral tool to characterize phase transitions where a direct gap closes (and reopens), typically occurring for insulators with topological properties. The power of this characteri...
Saved in:
Published in: | Physical review letters 2021-01, Vol.126 (1), p.016803-016803, Article 016803 |
---|---|
Main Authors: | , , , , , , |
Format: | Article |
Language: | English |
Subjects: | |
Citations: | Items that this one cites Items that cite this one |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | We establish the quantum fluctuations ΔQ_{B}^{2} of the charge Q_{B} accumulated at the boundary of an insulator as an integral tool to characterize phase transitions where a direct gap closes (and reopens), typically occurring for insulators with topological properties. The power of this characterization lies in its capability to treat different kinds of insulators on equal footing, being applicable to transitions between topological and nontopological band, Anderson, and Mott insulators alike. In the vicinity of the phase transition, we find a universal scaling ΔQ_{B}^{2}(E_{g}) as a function of the gap size E_{g} and determine its generic form in various dimensions. For prototypical phase transitions with a massive Dirac-like bulk spectrum, we demonstrate a scaling with the inverse gap in one dimension and a logarithmic one in two dimensions. |
---|---|
ISSN: | 0031-9007 1079-7114 |
DOI: | 10.1103/PhysRevLett.126.016803 |