Pauli spin blockade in undoped Si/SiGe two-electron double quantum dots

TL;DR

This paper demonstrates the realization of double quantum dots in undoped Si/SiGe heterostructures, observing Pauli spin blockade, which is crucial for coherent spin control in silicon-based quantum computing.

Contribution

It introduces a double top-gated design for undoped Si/SiGe quantum dots and confirms spin blockade observation in two-electron configurations.

Findings

Reliable depletion to zero charge occupancy

Charge sensing confirms electrostatic control

Observation of Pauli spin blockade in silicon quantum dots

Abstract

We demonstrate double quantum dots fabricated in undoped Si/SiGe heterostructures relying on a double top-gated design. Charge sensing shows that we can reliably deplete these devices to zero charge occupancy. Measurements and simulations confirm that the energetics are determined by the gate-induced electrostatic potentials. Pauli spin blockade has been observed via transport through the double dot in the two electron configuration, a critical step in performing coherent spin manipulations in Si.