Applied Physics Letters

Magnetically switched quantum waveguide qubit

Jason S. Harris, Richard Akis, David K. Ferry

Published Oct 1, 2001• 34 citations

Abstract

Recently, quantum computing has gained notoriety as a computational method that has the possibility to greatly increase the speed of calculations compared with traditional, binary computing. To this end, simulations of a quantum controlled-not gate implemented by a quantum waveguide are examined. The waveguide is composed of two quantum wires and a tuned coupling region and the simulations consist of a solution to Schrödinger’s equation via the Usuki method of mode matching. The use of Gaussian wave packets in previous work on this topic is questioned and various methods of tuning the coupling region in order to guide the quantum wave are investigated. Simulations are shown for a tuned waveguide in which the wave can be switched by the application of an external magnetic field.

DOI: 10.1063/1.1405428

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