S.M.A.R.T. Lab -

Dr. Mark Harrison
BS-ME 2004, MS-NE 2005, PhD-NE 2009; On a research project with Prof. McGregor, Dr. Mark Harrison designed multi-zone modified vertical Bridgman and Stockbarger furnaces, purification systems, and analysis systems to study the effects of aliovalent doping of lanthanide halide scintillators. He purified the starting materials and grew several LaBr₃ and CeBr₃ scintillating crystals with the furnaces that he designed and built. The result of the study indicated that the CeBr₃ is readily hardened with select aliovalent dopants without degrading light yield. Energy resolution from the experimental crystals was measured to be 4% FWHM at 662 keV. Dr. Mark Harrison holds the distinction of being the first PhD student to graduate from the SMART Laboratory radiation detector program. At graduation, Dr. Harrison had 24 published papers in archival journals and conference records. Following graduation, Dr. Harrison became an assistant professor in Nuclear Engineering at the University of Florida for two years. Afterwards, Dr. Harrison was awarded a Weinberg fellowship where he worked at Oak Ridge National Laboratory for nearly five years. Dr. Harrison then moved to Argonne National Laboratory where served as the Director of the Radiation Detection Group. In 2016, Dr. Harrison returned to KSU to temporarily to assist with projects involving the INL Hodoscope. After the completion of the project, Dr. Harrison has since moved on. Advisor: Douglas S. McGregor

Mark Harrison

Mark Harrison carefully etches and cleans a quartz ampoule to be used for reacting Cd, Zn, and Te.

Mark Harrison and Dr. McGregor discuss the details of a new ampoule design for the growth furnace.

Thermal anneal of a quartz ampoule at 1200 oC in a high temperature furnace tube.

Reacting Cd,Zn, and Te to produce CdZnTe is an exothermic process. In order to keep the melted Cd,Zn, and Te materials from breaking the ampoule, it is important to first coat the quartz with a clean and vitrified film of carbon.

Simulated furnace temperature distributions.

From left to right, Martin Ohmes, Dr. McGregor, and Mark Harrison visit the aircraft carrier Midway after attending the 2005 SPIE conference in San Diego.

Growing CdZnTe is simply not enough for Mark. He is also growing LaBr3 now, shown here inspecting one of his first ingots.