Obituary of Jan Tauc

Jan Tauc, a pioneer in semiconductor physics,died peacefully of heart failure after a period of declining health following the death of his wife Vera. They had moved to the West after retiring from Brown so as to be near their children’s families.

Jan was born in Pardubice, Bohemia(now the Czech Republic) In 1932 his father, a post-office accountant, was transferred to Opava (Sudetenland) a town annexed by Hitler in 1938. Jan vividly recalled how the family, not ethnic German, was given a few hours to leave. His father was transferred to Brno (Moravia) and Jan obtained a three-year fellowship to continue high school in Nimes (France). German occupation of the Czech part of the republic forced him to return, after only one year, to Brno where he finished his high school degree, but the Nazis had closed the universities. The war started in 1939. Jan was allowed to attend a two-year technical school while working at a factory engaged in weapons production. In his “free time” he taught himself physics and mathematics. As the war ended, universities reopened with an overwhelming number of students and a shortage of professors (many died in the war or in concentration camps). Jan got his E.E. degree in two years and in 1949 a degree of Dr. of technical sciences at Charles University in Prague. During this time he married Vera Koubelova.They had two children: Elena and Jan Jr.

Having heard of the discovery of the transistor, Jan began research in the field, managing to build the first point-contact transistor in the country. In 1952 the communists founded the Czechoslovak Academy of Sciences (CSAV) for the purpose of centralizing scientific research. Contrary to the universities, it offered its members a certain degree of political laxity. Jan, although not a party member, was asked to head the Semiconductors Department of its Institute of technical physics, a position he held til 1969 together with that of Professor at Charles University. His department soon achieved regognition on both sides of the Iron Curtain and Jan was allowed to attend the 4th International Conference on the Physics of Semiconductors (ICPS) in Rochester, NY, where he convinced the committee to choose Prague as the venue for the next ICPS. The 5th ICPS thus took place there in 1960, with Jan as chair of the program committee. It was the first such event held in the communist world.

Jan was interested in photovoltaic, thermoelectric and optical properties of crystalline semiconductors, having collaborated with Antoncik and Abraham to unravel the role of the spin-orbit splitting in the dielectric function. in the mid.1960’s he became interested in amorphous semiconductors due to their ease of preparation and photovoltaic applications. His paper with the Rumanian Grigorovici and Vancu on the electronic properties of amorphous germanium became the basis of semiempirical studies of amorphous structures and led to the often-used eponym “Tauc gap”. Research on amorphous semiconductors and metals occupied much of his subsequent scientific life.

In the spring of 1969, shortly after the invasion of Czechoslovakia by the Russians, Jan was still able to leave the country and travel with his family to Bell for a 12 months stay. The idea to emigrate had not crossed his mind until October, when he received a letter from the CSAV revoking his leave and demanding immediate return under threat of prosecution. Cardona and wife, close friends, went to Murray Hill to help them sort out the agonizing situation. They hinted the possibility of a faculty position at Brown. After this position materialized, in Physics and Engineering, Jan accepted it. He held it for 22 years, until retirement in 1992. In Prague he was sentenced in absentia to 5 years in jail.

Jan’s scientific life can be divided into two nearly equal periods of about 20 years each: Prague and Providence. It is remarkable that he was able to produce such influential papers under the precarious economic and political conditions in Prague. His most cited paper (over 1500 citations) belongs to this period; it is this work that secured him the position at Brown. In Dec.1987 he and his Brown coworkers Maris and Thomsen, were issued a valuable patent for a method to investigate properties of thin films using picosecond spectroscopy. He authored or edited several books and was editor of three important professional journals.

Jan received numerous honors including membership in the NAS, the Isakson Prize and the Adler award of the APS, and De Scientia et Humanitate Optime Meritis Medal from the Czech Academy.