Ultrasmall particle detection using a submicron Hall sensor

Journal Article · Sat May 15 00:00:00 EDT 2010 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.3360584· OSTI ID:21476229

Kazakova, O; Gallop, J ^[1]; Panchal, V ^[1]; See, P ^[1]; Cox, D C ^[1]; Spasova, M ^[2]; Cohen, L F ^[3]

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1. National Physical Laboratory, Teddington TW11 0LW (United Kingdom)
2. Center for Nanointegration, University of Duisburg-Essen, Duisburg 47048 (Germany)
3. Imperial College London, London SW7 2BW (United Kingdom)

We demonstrate detection of a single FePt nanoparticle (diameter 150 nm, moment {approx}10{sup 7} {mu}{sub B}) using an ultrasensitive InSb Hall sensor with the bar lateral width of 600 nm. The white noise of a typical nanodevice, S{sub V}{sup 1/2{approx_equal}}28 nV/{radical}Hz, is limited only by two-terminal resistance of the voltage leads which results in a minimum field sensitivity of the device B{sub min}=0.87 {mu}T/{radical}Hz. To detect a single FePt bead, we employed a phase-sensitive method based on measuring the ac susceptibility change in a bead when exposed to a switched dc magnetic field. Such nano-Hall devices, enabling detection of potentially even smaller moments, are of considerable significance both for nanomagnetic metrology and high sensitivity biological and environmental detectors.

• OSTI ID: 21476229
• Journal Information: Journal of Applied Physics, Vol. 107, Issue 9; Conference: 11. joint MMM-Intermag conference, Washington, DC (United States), 18-22 Jan 2010; Other Information: DOI: 10.1063/1.3360584; (c) 2010 American Institute of Physics; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

77 NANOSCIENCE AND NANOTECHNOLOGY
ELECTRIC CONDUCTIVITY
ELECTRIC POTENTIAL
HALL EFFECT
INDIUM ANTIMONIDES
INTERMETALLIC COMPOUNDS
IRON
MAGNETIC FIELDS
MAGNETIC SUSCEPTIBILITY
NANOSTRUCTURES
NOISE
PARTICLES
PLATINUM
SENSITIVITY
SENSORS
TRANSDUCERS
ALLOYS
ANTIMONIDES
ANTIMONY COMPOUNDS
ELECTRICAL PROPERTIES
ELEMENTS
INDIUM COMPOUNDS
MAGNETIC PROPERTIES
METALS
PHYSICAL PROPERTIES
PLATINUM METALS
PNICTIDES
TRANSITION ELEMENTS