Interplay of Electric Dipole Spin Resonance and Multilevel Landau-Zener Interference in p-Type Silicon Quantum Dots

TL;DR

This study investigates microwave-induced spin dynamics in p-type silicon quantum dots, revealing complex resonance behaviors due to the interplay of spin-orbit effects and multilevel Landau-Zener interference, with implications for spin qubit control.

Contribution

It demonstrates the combined effects of EDSR and MLLZ interference on spin resonance spectra in silicon quantum dots, supported by numerical simulations.

Findings

Observation of more than two resonance lines in PSB leakage current.

Main resonance exhibits both positive and negative peaks as magnetic field varies.

Numerical simulations agree with experimental spectra.

Abstract

In this work, we examine microwave responses of the Pauli spin blockade (PSB) leakage current through a p-type silicon double quantum dot. We observe more than the expected two resonance lines with the main resonance line exhibits both positive and negative peaks as a function of the magnetic field, corresponding to enhancement and suppression of the PSB leakage current, respectively. We attribute the observed spectra to the interplay between two spin rotation mechanisms: spin-orbit-mediated electric dipole spin resonance (EDSR) and multilevel Landau-Zener (MLLZ) interference, both of which are present in electrically driven devices with strong spin-orbit coupling (and enhanced in the vicinity of orbital level crossings). A numerical simulation taking into account both mechanisms show agreement with the experimental results. While these unconventional spectral behaviours can be readily suppressed away from the orbital level crossing or in devices with weak spin-orbit coupling, our study showcases the potential complexity of spin-rotating mechanisms for electrically driven spin qubits.