Massless and quantized modes of kinks in the phase space of superconducting gaps

Abstract

We investigated quantized modes of kinks in the phase space of superconducting gaps in a superconductor with multiple gaps. The kink is described by the sine-Gordon model in a two-gap superconductor and by the double sine-Gordon model in a three-gap superconductor. A fractional-flux vortex exists at the edge of the kink, and a fractional-flux vortex will be stable in a three-gap superconductor with time-reversal symmetry breaking. The kink and fractional-flux vortex exhibit massless modes as a sliding motion. We show further that there are one zero-energy mode (massless mode) and quantized excitation modes in kinks, which are characteristic features of multi-gap superconductors. The equation of quantized modes for the double sine-Gordon model is solved numerically. The correction to the ground-state energy is calculated based on the renormalization theory.

9 pages, 8 figures

References in corpus (12)

• Type-1.5 Superconductors
• Chiral CP^2 skyrmions in three-band superconductors
• Magnetic response of mesoscopic superconducting rings with two order parameters
• Field- and temperature induced topological phase transitions in the three-dimensional $N$-component London superconductor
• Phase textures induced by dc current pairbreaking in multilayer structures and two-gap superconductors
• Stability of fractional vortex states in a two-band mesoscopic superconductor
• Electronic correlations stabilizing time-reversal broken chiral superconductivity in single-trilayer TiSe${}_2$
• Two-dimensional vortex behavior in highly underdoped YBa_2Cu_3O_{6+x} observed by scanning Hall probe microscopy
• Stabilizing fractional vortices in multiband superconductors with periodic pinning arrays
• Chiral sine-Gordon model
• Fluctuation-induced Nambu-Goldstone bosons in a Higgs-Josephson model
• Renormalization group theory of effective field theory models in low dimensions

Cited by in corpus (6)

• Mechanism of High-Temperature Superconductivity in Correlated-Electron Systems
• Wobbling kinks in a two-component scalar field theory: Interaction between shape modes
• Solitary oscillations and multiple antikink-kink pairs in the double sine-Gordon model
• Zero-energy modes, fractional fermion numbers and the index theorem in a vortex-Dirac fermion system
• Fractional skyrmion and absence of low-lying Andreev bound states in a micro fractional-flux quantum vortex
• Unconventional and anomalous magnetic field distribution in a bilayer superconductor with geometric constraints