Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Toward the manipulation of a single spin in an AlGaAs/GaAs single-electron transistor

Sami Amasha, Kenneth MacLean, Dominik M. Zumbühl, Iuliana P. Radu, M. A. Kastner, Micah P. Hanson, Arthur C. Gossard

Published May 5, 2006• 6 citations

Abstract

Single-electron transistors (SETs) are attractive candidates for spin qubits. An AlGaAs/GaAs SET consists of a confined two-dimensional droplet of electrons, called an artificial atom or quantum dot, coupled by tunnel barriers to two conducting leads. Controlling the voltages on the lithographic gates that define the quantum dot allows us to confine a single electron in the dot, as well as to adjust the tunnel barriers to the leads. By applying a magnetic field, we can split the spin-up and spin-down states of the electron by an energy |g|μBB; the goal is to utilize coherent superpositions of these spin states to construct a qubit. We will discuss our attempts to observe electron spin resonance (ESR) in this system by applying magnetic fields at microwave frequencies. Observation of ESR would demonstrate that we can manipulate a single spin and allow us to measure the decoherence time T2*.

DOI: 10.1117/12.665548

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