Browse Prior Art Database

Temperature-Stabilized Magnetic Field Sensor

IP.com Disclosure Number: IPCOM000036535D
Original Publication Date: 1989-Oct-01
Included in the Prior Art Database: 2005-Jan-29
Document File: 2 page(s) / 28K

Publishing Venue

IBM

Related People

Lambert, SE: AUTHOR [+3]

Abstract

Disclosed is the concept of stabilizing the temperature of a superconducting magnetic field sensor.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 52% of the total text.

Page 1 of 2

Temperature-Stabilized Magnetic Field Sensor

Disclosed is the concept of stabilizing the temperature of a superconducting magnetic field sensor.

The electrical resistance R of a superconductor is strongly influenced by both temperature and magnetic field. Application of superconductors to the detection of magnetic fields may therefore require temperature stability of the detecting element to avoid spurious indications of changes in magnetic field.

The temperature of a superconducting magnetic field sensor can be actively stabilized by using a heater and a temperature-sensitive element all placed in good thermal contact with one another. Appropriate materials exist which exhibit temperature-dependent variations of properties such as dielectric constant, electrical resistance, or conductance across a pn junction. The particular application would determine how sensitive this temperature-dependent property could be to magnetic fields.

One application of such a sensor is for the detection of magnetically encoded data from a rotating surface, one example of which is a computer disk drive. In this case, electronic temperature stabilization circuitry, such as that shown in the figure, can be used to vary the power applied to the superconducting element in such a way as to keep the resistance (averaged over a suitable time constant) at a value which is a fixed fraction of the normal state resistance. This temperature control circuit is designed to have no significant response to the high frequency resistance changes associated with magnetic signals. The data recorded on the disk are detected as voltage changes across the superconducting element or as changes in the current into that element, depending on the bias scheme selected. The advantage of this scheme is that a...