Electrotunable artificial molecules based on van der Waals heterostructures

Abstract

Quantum confinement has made it possible to detect and manipulate single-electron charge and spin states. The recent focus on two-dimensional (2D) materials has attracted significant interests on possible applications to quantum devices, including detecting and manipulating either single-electron charging behavior or spin and valley degrees of freedom. However, the most popular model systems, consisting of tunable double-quantum-dot molecules, are still extremely difficult to realize in these materials. We show that an artificial molecule can be reversibly formed in atomically thin MoS2 sandwiched in hexagonal boron nitride, with each artificial atom controlled separately by electrostatic gating. The extracted values for coupling energies at different regimes indicate a single-electron transport behavior, with the coupling strength between the quantum dots tuned monotonically. Moreover, in the low-density regime, we observe a decrease of the conductance with magnetic field, suggesting the observation of Coulomb blockade weak anti-localization. Our experiments demonstrate for the first time the realization of an artificial quantum-dot molecule in a gated MoS2 van der Waals heterostructure, which could be used to investigate spin-valley physics. The compatibility with large-scale production, gate controllability, electron-hole bipolarity, and new quantum degrees of freedom in the family of 2D materials opens new possibilities for quantum electronics and its applications.

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• 2D materials and van der Waals heterostructures
• The Valley Hall Effect in MoS2 Transistors
• Magnetic Control of Valley Pseudospin in Monolayer WSe2
• Demonstration of Entanglement of Electrostatically Coupled Singlet-Triplet Qubits
• Fast pick up technique for high quality heterostructures of bilayer graphene and hexagonal boron nitride
• Ultrafast Manipulation of Valley Pseudospin
• Valley Polarization by Spin Injection in a Light-Emitting van der Waals Heterojunction
• Valley-spin blockade and spin resonance in carbon nanotubes
• Electrostatically confined monolayer graphene quantum dots with orbital and valley splittings
• Spin-valley relaxation and quantum transport regimes in two-dimensional transition metal dichalcogenides
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Cited by in corpus (29)

• Semiconductor Quantum Computation
• Nanomaterials for Quantum Information Science and Engineering
• Gate-Tunable Quantum Dot in a High Quality Single Layer MoS${}_2$ Van der Waals Heterostructure
• Coulomb blockade in an atomically thin quantum dot coupled to a tunable Fermi reservoir
• Stable and scalable metallic phase on MoS2 using forming-gas microwave plasma
• Valley qubit in gated MoS${}_2$ monolayer quantum dot
• Dielectrics for Two-Dimensional Transition Metal Dichalcogenide Applications
• Impurity-assisted electric control of spin-valley qubits in monolayer MoS${}_2$
• Gate-Controlled Quantum Dots Based on Two-Dimensional Materials
• Gate-defined, Accumulation-mode Quantum Dots in Monolayer and Bilayer WSe${}_2$
• Spin-valley system in a gated MoS${}_2$-monolayer quantum dot
• Gate controlled quantum dots in monolayer WSe2
• Valley two-qubit system in a MoS${}_2$-monolayer gated double quantum dot
• The effect of valley, spin and band nesting on the electronic properties of gated quantum dots in a single layer of transition metal dichalcogenides (TMDCs)
• Quantum transport through MoS${}_2$ constrictions defined by photodoping
• Gate defined quantum dot realized in a single crystalline InSb nanosheet
• Non-Destructive Low-Temperature Contacts to MoS2 Nanoribbon and Nanotube Quantum Dots
• Coherent Charge Oscillations in a Bilayer Graphene Double Quantum Dot
• Coulomb Blockade Spectroscopy of a ${\mathrm{MoS}}_2$ Nanotube
• Theory of valley-resolved spectroscopy of a Si triple quantum dot coupled to a microwave resonator
• Molecular Switching Operation in Gate Constricted Interface of MoS${}_2$ and hBN Heterostructure
• Tunable p-n junction barriers in few-electron bilayer graphene quantum dots
• Valley-selective energy transfer between quantum dots in atomically thin semiconductors
• Coherent Transport in Y-Junction Graphene Waveguide
• Preparation and Readout of Multielectron High-Spin States in a Gate-Defined GaAs/AlGaAs Quantum Dot
• Theory of field-modulated spin-valley-orbital pseudospin physics
• Gate-defined single-electron transistors in twisted bilayer graphene
• Flavor Quantum Dots and Artificial Quark Model in Transition Metal Dichalcogenides
• Spin-valley qubits in gated quantum dots in a single layer of transition metal dichalcogenides