Magnetic Properties of Thin Films

This spectroscopic image shows what are called microwave-frequency magnetic resonances of an array of parallel, metallic thin film nanowire "stripes". The peak in the center reflects resonances occurring at the stripe edges.  The strong horizontal bar of violet, black, and white, is due to resonances in the body of the stripes.

Image Credit: Brian Maranville

A research team from NIST, IBM and MIT recently demonstrated a spectroscopic technique for measuring the magnetic properties of the edges of nickel-iron alloy thin films. The thin films of metal were arranged in an array of parallel nanowires (called “stripes”) atop a silicon disk. The researchers beamed microwaves of different frequencies over the stripes and measured the magnetic vibrations or resonances that resulted. Because a thin film’s edge resonates differently from its center, the researchers were able to determine how the edge affects the magnetic properties of the film. The results of this work may impact the design of future nanoscale electronics. 

This spectroscopic image shows what are called microwave-frequency magnetic resonances of an array of parallel, metallic thin film nanowire "stripes". The peak in the center reflects resonances occurring at the stripe edges. The strong horizontal bar of violet, black, and white, is due to resonances in the body of the stripes. 

Dr. Robert D. McMichael at NIST was the scientist in charge of the overall research project. Dr. David Abraham at IBM generously made repeated, customized samples for the NIST team. Dr. Brian Maranville, a member of APS, was the research physicist in charge of measurements and data organization. 

Measurements from the Edge: Magnetic Properties of Thin Films