Alexei Lvovich Efros (Russian: Алексей Львович Эфрос, born 1938) is an American theoretical physicist who specializes in condensed matter physics.
Following graduation, he continued working at the Ioffe Institute and in the process received a second PhD in 1972 in semiconductor physics.
In 1986, he received the Landau Prize in theoretical physics from the Soviet Academy of Sciences.
During the dissolution of the Soviet Union in 1989 he emigrated to the United States and was a visiting distinguished scholar at University of California, Riverside.
In 1992, he was elected a fellow of the American Physical Society "for his work on the theory of transport in disordered systems".