Hartman graduated in 1934 from the
University of Nevada with a B.S. in electrical engineering and in 1938 from
Cornell University with a Ph.D. in physics. His thesis advisor was Lloyd P. Smith (1904–1988). Hartman was a physics instructor at Cornell for the academic year 1938–1939. From 1939 to 1946 he worked at
Bell Telephone Laboratories. During WW II he worked with
James Brown Fisk and
Homer D. Hagstrum in the development of centimeter-wave generators for airborne radar. Hartman was a faculty member in the physics department of Cornell University from 1946 to 1983, when he retired as professor emeritus. From 1971 to 1973 he was the associate director of Cornell's School of Applied and Engineering Physics. He helped to establish the
Cornell High-Energy Synchrotron Source (CHESS). Upon his death he was survived by his widow, three daughters, two grandchildren, and four great-grandchildren. ==Selected publications==