Optical detection of small signal magnetic fields using magnetostrictive cantilevers
Open Access
Author:
Curwen, Christopher Adam
Area of Honors:
Electrical Engineering
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
Srinivas A Tadigadapa, Thesis Supervisor Dr. Julio V. Urbina, Thesis Honors Advisor
Keywords:
Magnetostriction Cantilever Vibrometer Position Sensitive Photo Detector
Abstract:
Recent technologic developments have taken advantage of the magnetoelectric effect to build small signal magnetic field sensors with controlled detection of up to pico-Tesla magnetic fields. Many of these sensors are too large for certain applications, but promising designs for magnetoelectric resonant gate transistors that can be integrated with CMOS based signal processing circuits on a silicon substrate have shown nano-Tesla sensitivities and could potentially lead the way for smart sensor systems.
This honors thesis presents the optical characterization of the micro machined titanium/ Metglas® magnetostrictive cantilevers currently used in MERGT designs for the purpose of providing evidence of the functionality of the magnetostrictive cantilever as a tool for detecting magnetic fields. The noise characteristics of cantilevers and deflections of DC biased cantilevers in response to small signal magnetic fields are presented using two different experimental setups. The first setup uses the response of a position sensitive photo detector to a laser reflecting off the cantilevers, while the second setup uses a laser doppler vibrometer to directly measure the movement of the cantilevers. The following will provide a detailed description and evaluation of experimental setups and results of these optical measurements.
