title: A high-bandwidth spintronic position sensor.
abstract: Position sensing with resolution down to the scale of a single atom is of key importance in nanoscale science and engineering. However, only optical-sensing methods are currently capable of non-contact sensing at such resolution over a high bandwidth. Here, we report a new non-contact, non-optical position-sensing concept based on detecting changes in a high-gradient magnetic field of a microscale magnetic dipole by means of spintronic sensors. Experimental measurements show a sensitivity of up to 40 Ω/μm, a linear range greater than 10 μm and a noise floor of 0.5 pm/√[Hz]. Also shown is the use of the sensor for position measurements for closed-loop control of a high-speed atomic force microscope with a frame rate of more than 1 frame/s.
authors.affiliation: IBM Research-Zurich, Säumerstrasse 4, 8803 Rüschlikon, Switzerland. Automatic Control Laboratory, Swiss Federal Institute of Technology, Physikstrasse 3, 8092 Zurich, Switzerland.
authors.forename: Tomas
authors.initials: T
authors.lastname: Tuma
authors.forename: Angeliki
authors.initials: A
authors.lastname: Pantazi
authors.forename: Deepak R
authors.initials: DR
authors.lastname: Sahoo
authors.forename: Philipp
authors.initials: P
authors.lastname: Eib
authors.forename: Gian
authors.initials: G
authors.lastname: Salis
authors.forename: Haris
authors.initials: H
authors.lastname: Pozidis
authors.forename: Abu
authors.initials: A
authors.lastname: Sebastian