Pauli Spin Blockade of Heavy Holes in a Silicon Double Quantum Dot

TL;DR

This paper demonstrates Pauli spin blockade in heavy holes within a silicon double quantum dot, revealing strong spin-orbit interaction and providing insights for fast electrical spin manipulation in quantum computing.

Contribution

It reports the first observation of Pauli spin blockade in heavy holes in silicon quantum dots and characterizes the spin relaxation mechanisms and spin-orbit interaction strength.

Findings

Pauli spin blockade observed in heavy hole regime.

Heavy hole g-factor approximately 0.93.

Spin-orbit interaction strength around 110 μeV.

Abstract

In this work, we study hole transport in a planar silicon metal-oxide-semiconductor based double quantum dot. We demonstrate Pauli spin blockade in the few hole regime and map the spin relaxation induced leakage current as a function of inter-dot level spacing and magnetic field. With varied inter-dot tunnel coupling we can identify different dominant spin relaxation mechanisms. Applying a strong out-of-plane magnetic field causes an avoided singlet-triplet level crossing, from which the heavy hole g-factor $\sim$ 0.93, and the strength of spin-orbit interaction $\sim$ 110 $\mu$eV, can be obtained. The demonstrated strong spin-orbit interaction of heavy hole promises fast local spin manipulation using only electrical fields, which is of great interest for quantum information processing.