Agenda

  Observation of a Kondo impurity state and universal screening using a charge pseudospin

Anne Anthore (C2N)

Horaire/Time : le mardi 20 juin 2023 à 14:00

Lieu/Place : Visio-conférence Zoom hybride depuis Salle Nevill Mott D420, Institut Néel

Zoom link: https://univ-grenoble-alpes-fr.zoom.us/j/91808901596?pwd=UWZ2cml2N1VBOEZBenk0d3RJek9rdz09

Résumé/Abstract : The Kondo effect, deriving from a local magnetic impurity mediating electron-electron interactions, constitutes a flourishing basis for understanding a variety of intricate many-body problems. Its experimental implementation in tunable circuits has made possible advances through well-controlled investigations. However, these have mostly concerned transport properties, whereas thermodynamic observations – notably the fundamental measurement of the spin of the Kondo impurity – remain elusive in test-bed circuits. In this talk, I will present how we directly observe the state of the impurity and its progressive screening with a novel combination of a « charge » Kondo circuit and a charge sensor. We establish the universal renormalization flow from a single free spin to a screened singlet, the associated reduction in the magnetization, and the relationship between scaling Kondo temperature and microscopic parameters.