Skip to content
6CCVD Research

Preserving Coulomb blockade in transport spectroscopy of quantum dots by dynamical tunnel barrier compensation

At a Glance

Section titled ā€œAt a Glanceā€
MetadataDetails
Publication Date2024-12-23
JournalApplied Physics Letters
AuthorsVarsha Jangir, Deepak Shah, Santanu Samanta, Sanjay Rastogi, Harvey E. Beere
InstitutionsUniversity of Cambridge, Indian Institute of Technology Bombay
Citations2

Abstract

Section titled ā€œAbstractā€

Surface-gated quantum dots (QDs) in semiconductor heterostructures represent a highly attractive platform for quantum computation and simulation. However, in this implementation, the barriers through which the QD is tunnel-coupled to source and drain reservoirs (or neighboring QDs) are usually non-rigid and capacitively influenced by the plunger-gate voltage (VP). In transport spectroscopy measurements, this leads to suppression of current and lifting of the Coulomb blockade for increasing negative and positive values of VP, respectively. Consequently, the charge-occupancy of the QD can be tuned over a rather small range of VP. By dynamically tuning the tunnel barriers to compensate for the capacitive effect of VP, here we demonstrate a protocol that allows Coulomb blockade to be preserved over a remarkably large span of charge-occupancies, as demonstrated by clean Coulomb diamonds and well-resolved excited state features. The protocol will be highly beneficial for automated tuning and identification of the gate voltage space for optimal operation of QDs in large arrays required for a scalable spin quantum computing architecture.

Tech Support

Section titled ā€œTech Supportā€

Original Source

Section titled ā€œOriginal Sourceā€

References

Section titled ā€œReferencesā€
  1. 1998 - Quantum computation with quantum dots [Crossref]
  2. 2005 - Coherent manipulation of coupled electron spins in semiconductor quantum dots [Crossref]
  3. 2017 - Coherent shuttle of electron-spin states [Crossref]
  4. 2018 - A crossbar network for silicon quantum dot qubits [Crossref]
  5. 2020 - Nagaoka ferromagnetism observed in a quantum dot plaquette [Crossref]
  6. 2021 - Quantum Simulation of Antiferromagnetic Heisenberg Chain with Gate-Defined Quantum Dots [Crossref]
  7. 2017 - Quantum simulation of a Fermi-Hubbard model using a semiconductor quantum dot array [Crossref]
  8. 2012 - Signatures of Majorana fermions in hybrid superconductor-semiconductor nanowire devices [Crossref]
  9. 2024 - A two-site Kitaev chain in a two-dimensional electron gas [Crossref]
  10. 1996 - Shell filling and spin effects in a few-electron quantum dot [Crossref]

Reads Similar to This

Robust Quantum-Network Memory Using Decoherence-Protected Subspaces of Nuclear Spins Optimization of Temperature Sensitivity Using the Optically Detected Magnetic-Resonance Spectrum of a Nitrogen-Vacancy Center Ensemble Top Heat Spreaders on GaN-based HEMT devices for improved thermal management