Coulomb blockade in Etched Single and Few Layer MoS2 Nanoribbons

TL;DR

This paper demonstrates Coulomb blockade phenomena in etched MoS2 nanoribbons, revealing quantum dot formation and potential for quantum information applications in two-dimensional materials.

Contribution

It reports the observation of Coulomb blockade and quantum dot formation in MoS2 nanoribbons, a novel platform for quantum device engineering.

Findings

Coulomb diamonds indicate single-electron tunneling.

Quantum dots as small as 10-35nm are formed.

Potential for spin-valley qubits in 2D materials.

Abstract

Confinement in two-dimensional transition metal dichalcogenides is an attractive platform for trapping single charge and spins for quantum information processing. Here, we present low temperature electron transport through etched 50-70nm MoS2 nanoribbons showing current oscillations as a function of gate voltage. On further investigations current through the device forms diamond shaped domains as a function of source-drain and gate voltage. We associate these current oscillations and diamond shaped current domains with Coulomb blockade due to single electron tunneling through a quantum dot formed in the MoS2 nanoribbon. From the size of the Coulomb diamond, we estimate the quantum dot size as small as 10-35nm. We discuss the possible origins of quantum dot in our nanoribbon device and prospects to control or engineer the quantum dot in such etched MoS2 nanoribbons which can be a promising platform for spin-valley qubits in two-dimensional transition metal dichalcogenides.