Single-charge detection by an atomic precision tunnel junction

Abstract

We demonstrate sensitive detection of single charges using a planar tunnel junction 8.5nm wide and 17.2nm long defined by an atomically precise phosphorus doping profile in silicon. The conductance of the junction responds to a nearby gate potential and also to changes in the charge state of a quantum dot patterned 52nm away. The response of this detector is monotonic across the entire working voltage range of the device, which will make it particularly useful for studying systems of multiple quantum dots. The charge sensitivity is maximized when the junction is most conductive, suggesting that more sensitive detection can be achieved by shortening the length of the junction to increase its conductance.

4 pages; 4 figures

References in corpus (4)

• Silicon Quantum Electronics
• Electron counting in quantum dots
• Excited-state spectroscopy on a nearly-closed quantum dot via charge detection
• Measurement of valley splitting in high-symmetry Si/SiGe quantum dots

Cited by in corpus (10)

• Three-electron spin qubits
• Single-shot single-gate RF spin readout in silicon
• The formation of nonequilibrium steady states in interacting double quantum dots: When coherences dominate the charge distribution
• Observation and origin of the $\Delta$-manifold in Si:P $\delta$-layers
• Finite coupling effects in double quantum dots near equilibrium
• 3-Dimensional Tuning of an Atomically Defined Silicon Tunnel Junction
• Uncovering anisotropic effects of electric high-moment dipoles on the tunneling current in $\delta$-layer tunnel junctions
• Influence of imperfections on tunneling rate in $\delta$-layer junctions
• Atomic-scale Control of Tunnel Coupling
• Quantifying Atom-scale Dopant Movement and Electrical Activation in Si:P Monolayers