Nikolai Delaunay, Jr. (aka Delone, Nikolai Borisovich; 22 May 1926 – 11 September 2008) was a Soviet physicist born in Leningrad, USSR (now Saint Petersburg, Russia).
[1][2] Delone, along with Maxim Ammosov and Vladimir P. Krainov, developed the ADK formula, relating tunneling ionization in laser fields.
[1] After the dissolution of the Soviet Union, he travelled abroad and worked on international collaborations on multiphoton physics.
[1] His son was Vadim Delaunay, a poet and dissident, who participated in the 1968 Red Square demonstration of protest against military suppression of the Prague Spring.
Delone published over 200 scientific papers, a four-book series on the physics of strong laser fields and on multiphoton physics, and a series of high-school level Russian textbooks.