Datta held Alexander von Humboldt Fellowships at the Institute for Physics, University of Dortmund, Germany, 1986–88; at Dortmund in 1994, at the Physikalisches Inst., Univ. of Bonn in 2002, at Dortmund in 2004, and Bonn in 2007. He also held Associateships of the International Centre for Theoretical Physics, Trieste, Italy, from 1991 to 1995, and of the Institute of Theoretical Physics Beijing, 1997–99.