Herbert Kroemer, 95, Dies; Laid Groundwork for Modern Technologies

Herbert Kroemer was born on Aug. 25, 1928, in the city of Weimar, Germany, the eldest of three brothers. His father was a civil servant and his mother took care of the home. Neither parent had finished high school, but they emphasized education for their children. (When Dr. Kroemer eventually decided to study physics, he recalled, his father asked what that was and whether he could make a living at it.)

The young Herbert displayed an immediate aptitude for math and physics, but he was also bored and disruptive. In math, he got into trouble by teaching some other students methods that they did not understand, whereupon the teacher made a deal with him: If he would refrain from disrupting the class, he did not have to turn in any work and would be guaranteed a top grade. He stuck to the deal.

After high school, he entered the University of Jena, about 15 miles southeast of Weimar. The entire region, which lay in East Germany, was by then under the jurisdiction of the Soviet Union, and Dr. Kroemer, like many students and professors, chafed under the restrictive government. After only a year, he decided to leave.

This was in 1948, during the Berlin Blockade, when the Allies were flying supplies into West Berlin after the Soviets had cut off railway, road and canal access. Dr. Kroemer, who had worked for the summer at Siemens, the technology company, stood in line for two days at the airport, then flew out on a British plane.

Before he left, he had written to several universities seeking admission. He eventually found a spot at the University of Göttingen, where he was tutored by Fritz Sauter, who specialized in solid-state physics. After Dr. Kroemer gave a colloquium on a new idea relating to transistors, Dr. Sauter suggested that he submit his paper for his master’s in theoretical physics. A year later, in 1952, Dr. Kroemer obtained his Ph.D.