English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We study a Kondo state that is strongly influenced by its proximity to anw^-1/2 singularity in the metallic host density of states. This singularityoccurs at the bottom of the band of a 1D chain, for example. We first analyzethe non-interacting system: A resonant state e_d, located close to the bandsingularity, suffers a strong `renormalization', such that a bound state iscreated below the bottom of the band in addition to a resonance in thecontinuum. When e_d is positioned right at the singularity, the spectral weightof the bound state is 2/3, irrespective of its coupling to the conductionelectrons. The interacting system is modeled using the Single Impurity AndersonModel, which is then solved using the Numerical Renormalization Group method.We observe that the Hubbard interaction causes the bound state to suffer aseries of transformations, including level splitting, transfer of spectralweight, appearance of a spectral discontinuity, changes in binding energy (thelowest state moves farther away from the bottom of the band), and developmentof a finite width. When e_d is away from the singularity and in theintermediate valence regime, the impurity occupancy is lower. As e_d movescloser to the singularity, the system partially recovers Kondo regimeproperties, i.e., higher occupancy and lower Kondo temperature T_K. Theimpurity thermodynamic properties show that the local moment fixed point isalso strongly affected by the existence of the bound state. When e_d is closeto the singularity, the local moment fixed point becomes impervious to chargefluctuations (caused by bringing e_d close to the Fermi energy), in contrast tothe local moment suppression that occurs when e_d is away from the singularity.We also discuss an experimental implementation that shows similar results tothe quantum wire, if the impurity's metallic host is an armchair graphenenanoribbon.

Quantum impurity with 2/3 local moment in 1D quantum wires: an NRG study