Year: 2025
Type: article
Abstract: Superconductivity is achieved by the pairing of electrons and phase coherence between the Cooper pairs. According to the Bardeen-Cooper-Schrieffer theory, quasiparticles with Bogoliubov dispersion exist in the superconducting state, leading to the particle-hole symmetric coherence peaks on the single particle tunneling spectrum. Here we report the observation of two kinds of tunneling spectra showing only one side of the coherence peak in the underdoped cuprate superconductor Bi2Sr2-xLaxCuO6, and we name the electronic states as half-Bogoliubons. Based on the model that two doped holes bind into a local pair within the 4a0 × 4a0 plaquette, we attribute the half-Bogoliubons to one-hole or three-hole intermediate states for phase coherence. An entanglement of distinct half-Bogoliubons would lead to the dynamic hopping of charge freedom, resulting in the phase coherence between the local pairs. Our results unravel a unique process for establishing the phase coherence through exchanging a charge between regions with local pairs. The authors report the observation of tunneling spectra with extremely asymmetric coherence peaks in the underdoped cuprate superconductor Bi2Sr2-xLaxCuO6. They argue that the extremely asymmetric peaks arise from ‘half-Bogoliubons’, corresponding to three-hole and one-hole excitations of the local pairing state of two holes per 4a0 × 4a0 plaquette.
Source: Nature Communications
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $6,990
OpenAlex ID: W4416959250