Direct observation of single-electron decay from an artificial nucleus

• Published in: Physica. E, Low-dimensional systems & nanostructures Vol. 6; no. 1; pp. 457 - 460
• Main Authors: Cooper, J, Smith, C.G, Ritchie, D.A, Linfield, E.H, Jin, Y, Launois, H
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-02-2000
• Subjects: Charge detector; Electrometer; Electron decay; Quantum dots; 29.40.W; 73.61; Quantum dots; Electrometer; 85.30.V; 84.37; Charge detector; Electron decay
• ISSN: 1386-9477; 1873-1759
• DOI: 10.1016/S1386-9477(99)00208-8

We describe the behaviour of an isolated quantum dot charged up with an excess of 30 electrons over its equilibrium value. A non-invasive voltage probe with a charge resolution of
e/10 is fabricated next to the dot and used to measure the electron decay rate. The system behaves like an artificial nucleus with the electron escape rate following a Poisson distribution. We observe times for tunnelling of electrons out of the dot in excess of 1000 s.