Entangled State Generation and Coherence in STM-ESR Geometries Using Quantum Master Equations

Experimental techniques using pulsed electron spin resonance (ESR) with scanning tunneling microscopy (STM) has uncovered a new method to generate entangled spin states using atomic sites prepared on a substrate [1]. In this work, we demonstrate the use of a newly developed NEGF-derived quantum master equation software (TimeESR) to model ESR-STM for realistic experimental conditions relevant to atomic-scale qubit systems. We predict changes in measured current on the STM tip within the time domain and correlate patterns in the current with the generation of a non-trivial entangled spin state. We also demonstrate the role of electron dynamics in the sequential regime on the coherence of the entangled state as a function of time.

[1] Yu Wang et al., Science 382, 87 (2023)