3/5/2015 Julia Cation
Written by Julia Cation
A paper written by Professor and Ralph A. Andersen Endowed Chair Bill King and his research group (with collaboration from Alexander Vakakis, the W. Grafton and Lillian B. Wilkins Professor) has been named one of 20 most accessed articles of 2014 in the journal Review of Scientific Instruments.
The abstract of the paper, entitled, “Atomic force microscope infrared spectroscopy on 15 nm scale polymer nanostructures” states, “We measure the infrared spectra of polyethylene nanostructures of height 15 nm using atomic force microscope infrared spectroscopy (AFM-IR), which is about an order of magnitude improvement over state of the art. In AFM-IR, infrared light incident upon a sample induces photothermal expansion, which is measured by an AFM tip.
The thermomechanical response of the sample-tip-cantilever system results in cantilever vibrations that vary in time and frequency. A time-frequency domain analysis of the cantilever vibration signal reveals how sample thermomechanical response and cantilever dynamics affect the AFM-IR signal. By appropriately filtering the cantilever vibration signal in both the time domain and the frequency domain, it is possible to measure infrared absorption spectra on polyethylene nanostructures as small as 15 nm.”First author on the paper, Jonathan Felts, is now an assistant professor of mechanical engineering at Texas A&M. Hanna Cho, the paper’s second author, is an assistant professor of mechanical engineering at Texas Tech, where she runs the Micro/Nano Multiphysical Dynamics Lab.