He served as a research assistant for the Whitman Archive from 2013 to 2018 and is currently in an advisory position. Stefan's research interests lie in the area of nineteenth-century American poetry and its intersections with science and technology. His scholarship related to Whitman has appeared in American Literature, College Literature, Walt Whitman Quarterly Review, and the South Central Review. Stefan's translation of Whitman's Jack Engle into German appeared in 2017 (Das Kulturelle Gedächtnis).