Quantum-Dot Cellular Automata using Buried Dopants

Abstract

The use of buried dopants to construct quantum-dot cellular automata is investigated as an alternative to conventional electronic devices for information transport and elementary computation. This provides a limit in terms of miniaturisation for this type of system as each potential well is formed by a single dopant atom. As an example, phosphorous donors in silicon are found to have good energy level separation with incoherent switching times of the order of microseconds. However, we also illustrate the possibility of ultra-fast quantum coherent switching via adiabatic evolution. The switching speeds are numerically calculated and found to be 10's of picoseconds or less for a single cell. The effect of decoherence is also simulated in the form of a dephasing process and limits are estimated for operation with finite dephasing. The advantages and limitations of this scheme over the more conventional quantum-dot based scheme are discussed. The use of a buried donor cellular automata system is also discussed as an architecture for testing several aspects of buried donor based quantum computing schemes.

Minor changes in response to referees comments. Improved section on scaling and added plot of incoherent switching times

References in corpus (7)

• Atomically precise placement of single dopants in Si
• Charge-based quantum computing using single donors in semiconductors
• Coherent electronic transfer in quantum dot systems using adiabatic passage
• Decoherence Rate of Semiconductor Charge Qubit Coupled to Acoustic Phonon Reservoir
• Measuring the decoherence rate in a semiconductor charge qubit
• Correlated charge detection for read-out of a solid state quantum computer
• Development and operation of the twin radio frequency single electron transistor for solid state qubit readout

Cited by in corpus (7)

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• Robust Charge-based Qubit Encoding
• Physics-based mathematical models for quantum devices via experimental system identification
• Charge-to-spin conversion of electron entanglement states and spin-interaction-free solid-state quantum computation
• A multiplexed single electron transistor for application in scalable solid-state quantum computing
• Electronic transport in Si:P delta-doped wires