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Conference on Precision Electromagnetic Measurements

Miniature DC SQUID devices for the detection of single atomic spin-flips: scaling of flux sensitivity with device dimension

Chris I. Pakes, Patrick Josephs-Franks, R.P. Reed

Published Nov 7, 2002• 0 citations
Publisher

Abstract

We report progress towards a SQUID based system capable of detecting single atomic spin-flips. The scaling of the flux sensitivity with SQUID loop dimension of miniature niobium DC SQUID devices is examined and shown experimentally to vary as predicted. Our smallest device, with loop size 3 /spl mu/m/spl times/3 /spl mu/m, is capable of detecting a few spins in a 1 Hz bandwidth.

DOI
10.1109/cpem.2000.850965

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We report progress towards a SQUID based system capable of detecting single atomic spin-flips. The scaling of the flux sensitivity with SQUID loop dimension of miniature niobium DC SQUID devices is examined and shown experimentally to vary as predicted. Our smallest device, with loop size 3 /spl mu/m/spl times/3 /spl mu/m, is capable of detecting a few spins in a 1 Hz bandwidth.
We report progress toward a superconducting quantum interference device (SQUID)-based system capable of detecting a few atomic spin-flips. The scaling of the flux sensitivity with SQUID loop dimension of miniature niobium dc SQUID devices is examined and shown experimentally to vary as predicted. Our smallest device, with loop size 3 /spl mu/m/spl times/3 /spl mu/m, is capable of detecting 40 spins in a 1-Hz bandwidth. We address the task of depositing a sample, of nanoscale dimension, within the SQUID loop.
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