6533b7d2fe1ef96bd125edcc
RESEARCH PRODUCT
Universal decay cascade model for dynamic quantum dot initialization.
Vyacheslavs KashcheyevsBernd Kaestnersubject
PhysicsCondensed Matter - Mesoscale and Nanoscale PhysicsStrongly Correlated Electrons (cond-mat.str-el)FOS: Physical sciencesGeneral Physics and AstronomyInitializationCoulomb blockade02 engineering and technologyDecoupling (cosmology)Electron021001 nanoscience & nanotechnology01 natural sciencesComputational physicsCondensed Matter - Strongly Correlated ElectronsQuantum dotCascadeQuantum mechanicsMesoscale and Nanoscale Physics (cond-mat.mes-hall)0103 physical sciencesMaster equationProbability distribution010306 general physics0210 nano-technologydescription
Dynamic quantum dots can be formed by time-dependent electrostatic potentials in nanoelectronic devices, such as gate- or surface-acoustic-wave-driven electron pumps. Ability to control the number of captured electrons with high precision is required for applications in fundamental metrology and quantum information processing. In this work we propose and quantify a scheme to initialize quantum dots with a controllable number of electrons. It is based on the stochastic decrease in the electron number of a shrinking dynamic quantum dot and is described by a nuclear decay cascade model with "isotopes" being different charge states of the dot. Unlike the natural nuclei, the artificial confinement is time-dependent and tunable, so the probability distribution for the final "stable isotopes" depends on the external gate voltage. We derive an explicit fitting formula to extract the sequence of decay rate ratios from the measurements of averaged current in a periodically driven device. This provides a device-specific fingerprint which allows to compare different devices and architectures, and predict the upper limits of initialization accuracy from low precision measurements.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2009-01-26 | Physical review letters |