The vibrating sample magnetometer (VSM) is a versatile tool used to quantify the magnetization of nanomaterials and magnetic samples. An important work in progress is the low-cost development of this state-of-the-art technique.
Bilal Aftab Usman, a physics graduate from the 2012 batch at LUMS is working on this project. Using a mechanical vibrator oscillating a sample inside a strong magnetic field, it is possible to pick up modulated magnetic signals from giant magnetoresistive (GMR) or Hall sensors. The acquired signal, owing to its exceedingly small signal-to-noise ratio is fed into a homemade lock-in amplifier. In the picture, Bilal is shown building and testing the various components of the system.