John Kearney

Status:  4th year undergraduate student

Project: Unexpected Structural and Electronic Behavior of Sn3N4

Advisor:  Dr. Ashkan Salamat

Email:  kearney@unlv.nevada.edu

Education:

  • B.S. in Physics will be completed in Spring 2018

John Kearney

Research:

My research involves static high pressure/temperature studies of various materials using laser heated and resistive heated diamond anvil cells (DAC).  Through my work I have carried out experiments in the multi-megabar pressure regime using a DAC.  I have used electrical discharge machining and laser drillers for gasket preparation, and single and triple grating spectrometers for Raman spectroscopy to measure pressure and collect data on samples.  Tin nitride has shown the remarkable behavior of a band gap energy that increases as pressure is increased, and my work on tin nitride has involved setting up an optical absorption system to measure bang gap energies in the visible range of samples at high pressure.

Both CO2 and Nd:YAG lasers have been used to laser heat conducting materials and wide band gap semi-conductors.  I have conducted X-ray diffraction and absorption at Argonne National Lab during these laser heating experiments to give insight to the structural and electronic behavior of Sn34.  Through the X-ray absorption experiments I have become familiar with performing DAC experiments using beryllium as a gasket material.  This highly toxic low-Z metal is necessary for absorption experiments so as not to scatter incident X-rays.

National Laboratories:

  • X-ray diffraction experiments at Argonne National Laboratory Advanced Photon source
  • X-ray absorption spectroscopy experiments at Argonne National Laboratory Advanced Photon Source

Collaborations with national lab scientists:

  • Collaboration with Dr. Changyong Park from Argonne National Laboratory Advanced Photon Source
  • Collaboration with Dr. Jesse Smith from Argonne National Laboratory Advanced Photon Source

Professional schools & workshops:

  • 2015 UNLV Extreme Crystals Weekend workship

Awards:

  • 2016 Russell L. & Brenda Frank Endowed Scholarship
  • 2016 NSF EPSCoR Undergraduate Research Opportunity scholarship

Presentations:

  • 2017 Poster presentation at SSAA annual review conference