Sensing the spin of an individual Ce adatom

TL;DR

This paper demonstrates a novel method to electrically detect the magnetic moment of a single Ce adatom using a Kondo-sensor tip, overcoming previous shielding challenges in rare earth element measurements.

Contribution

It introduces a new sensing technique employing a Kondo-screened tip to detect individual Ce atom magnetic moments via scanning tunneling spectroscopy.

Findings

Successfully detected magnetic moment of a single Ce atom

Calibrated sensor tip with Fe atom for accurate measurements

Demonstrated splitting of Kondo resonance as a sensing mechanism

Abstract

The magnetic moment of rare earth elements originates from electrons in the partially filled 4f orbitals. Accessing this moment electrically by scanning tunneling spectroscopy is hampered by shielding of outer-lying orbitals. Here we show that we can detect the magnetic moment of an individual Ce atom adsorbed on a Cu2N ultrathin film on Cu(100) by using a sensor tip that has its apex functionalized with a Kondo screened spin system. We calibrate the sensor tip by deliberately coupling it to a well characterized Fe atom. Subsequently, we use the splitting of the tip's Kondo resonance when approaching a spectroscopically dark Ce atom to sense its magnetic moment.