Dr. Joshua Cohn

Professor and Chairman
Fall 2017 classes:  PSC 101, PHY 362
email: cohn@physics.miami.edu 
voice: (305) 284 7123
Fax: (305) 284 4222
Rm 309, James L. Knight Physics Building
1320 Campo Sano Ave., Coral Gables, Fl. 33146

My research involves measuring low-temperature electronic, magnetic, and thermal properties of novel materials that manifest interesting physics and show some potential to be useful in future electronic devices. These physical properties measurements, like electrical conductivity, thermal conductivity, and thermoelectricity, involve attaching very small wires to small crystalline specimens (mm sized), cooling them in liquid cryogens (liquid nitrogen and liquid helium), and using specialized voltmeters, current sources, and occasionally high-field magnets to study their properties. A separate research effort involves making "thin films" of some of these same materials -- thin coatings of 100 or so atomic layers of a material of interest deposited on a crystalline insulating surface. The method of deposition involves a high-powered laser that vaporizes a "target" of the material of interest inside a high-vacuum chamber (pulsed-laser deposition). We study these films using x-ray crystallography (to determine their structural properties) and measure their low-temperature properties with the techniques mentioned above. Thin films are a first step toward making useful devices.

For more information please see my web site.