Alexei Yurievich Kitaev (Russian: Алексей Юрьевич Китаев; born August 26, 1963) is a Russian–American professor of physics at the California Institute of Technology and permanent member of the Kavli Institute for Theoretical Physics.[1] He is best known for introducing the quantum phase estimation algorithm and the concept of the topological quantum computer[2] while working at the Landau Institute for Theoretical Physics. He is also known for introducing the complexity class QMA and showing the 2-local Hamiltonian problem is QMA-complete, the most complete result for k-local Hamiltonians.[3] Kitaev is also known for contributions to research on a model relevant to researchers of the AdS/CFT correspondence started by Subir Sachdev and Jinwu Ye; this model is known as the Sachdev–Ye–Kitaev (SYK) model.[4]
Kitaev was educated in Russia, receiving an M.Sc. from the Moscow Institute of Physics and Technology (1986), and a Ph.D. from the Landau Institute for Theoretical Physics under the supervision of Valery Pokrovsky in 1989.[5] He served previously as a researcher (1999–2001) at Microsoft Research, a research associate (1989–1998) at the Landau Institute and a professor at Caltech (2002–present).[1]
In 2008 Kitaev was awarded a MacArthur Fellowship.
In July 2012, he was an inaugural awardee of the Breakthrough Prize in Fundamental Physics, the creation of physicist and internet entrepreneur, Yuri Milner.[6]
In 2015, he was jointly awarded the 2015 Dirac Medal by ICTP.[7]
In 2017, he was, together with Xiao-Gang Wen, the winner of the Oliver E. Buckley Condensed Matter Prize.[8]
In 2021, he was elected into the National Academy of Sciences.[9]
In 2024, he received the Henri Poincaré Prize from the International Association of Mathematical Physics.[10]
In 2024, he was awarded a 2024 Basic Science Lifetime Award in Theoretical Physics.
In February–March 2022, he signed an open letter by Breakthrough Prize laureates condemning the 2022 Russian invasion of Ukraine.[11]