Georgi Stefanov Nadjakov (8.01.1897 -24.02.1981) was a Bulgarian physicist, a member of the Bulgarian Academy of Sciences (1945) and its vice-president in 1945 — 58. He was born in Dupnitsa (now Stanke Dimitrov). He graduated from Sofia University (1920), and in 1925-26 worked in Paris with P. Langevin and M. Skłodowska-Curie. From 1927 he taught at Sofia University (professor from 1932, rector in 1947 — 52), and in 1946 — 71 he was director of the Physical Institute with the Atomic Scientific and Experimental Base of the Bulgarian Academy of Sciences.
His research was in the physics of dielectrics and semiconductors, magnetism and nuclear physics. He discovered the photoelectret state (1937).
He was an active public figure, chairman of the Bulgarian Committee for the Defence of Peace and a member of the World Peace Council. A foreign member of the USSR Academy of Sciences (1958). Dimitrov Prize (1950).