Loading…
The Higgs mode in disordered superconductors close to a quantum phase transition
The concept of mass generation by means of the Higgs mechanism was strongly inspired by earlier works on the Meissner–Ochsenfeld effect in superconductors. In quantum field theory, the excitations of longitudinal components of the Higgs field manifest as massive Higgs bosons. The analogous Higgs mod...
Saved in:
Published in: | Nature physics 2015-02, Vol.11 (2), p.188-192 |
---|---|
Main Authors: | , , , , , , , , , , , , |
Format: | Article |
Language: | English |
Subjects: | |
Citations: | Items that this one cites |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | The concept of mass generation by means of the Higgs mechanism was strongly inspired by earlier works on the Meissner–Ochsenfeld effect in superconductors. In quantum field theory, the excitations of longitudinal components of the Higgs field manifest as massive Higgs bosons. The analogous Higgs mode in superconductors has not yet been observed owing to its rapid decay into particle–hole pairs. According to recent theories, however, the Higgs mode should decrease below the superconducting pairing gap 2
Δ
and become visible in two-dimensional systems close to the superconductor–insulator transition. For experimental verification, we measured the complex terahertz transmission and tunnelling density of states of various thin films of superconducting NbN and InO close to criticality. Comparing both techniques reveals a growing discrepancy between the finite 2
Δ
and the threshold energy for electromagnetic absorption, which vanishes critically towards the superconductor–insulator transition. We identify the excess absorption below 2
Δ
as strong evidence of the Higgs mode in two-dimensional quantum critical superconductors.
The Higgs mechanism is best known for generating mass for subatomic particles. Less well-known is that the idea originated in the study of superconductivity, and can be tested in the laboratory. |
---|---|
ISSN: | 1745-2473 1745-2481 |
DOI: | 10.1038/nphys3227 |