A Low-Power, High-Sensitivity Micromachined Optical Magnetometer
Rahul R. Mhaskar, Svenja A. Knappe, John E. Kitching
We demonstrate a fiber-optically coupled optical magnetometer based on a microfabricated 87Rb vapor cell in a micromachined silicon sensor head. The cell is optically heated with light at 1.5 mm brought to the cell through an optical fiber and absorbed by colored filters attached to the cell windows. A second fiber-optically coupled probe beam optically pumps and interrogates the atoms. A sensitivity below 20 fΤ/√Hz is achieved in the frequency band from 15 Hz to 100 Hz. Such a sensor might find application in measurements of magnetic fields from biological sources such as the human heart and brain.