  Bi2Te3 compound has been theoretically predicted (1) to be a topological
insulator, and its topologically non-trivial surface state with a single Dirac
cone has been observed in photoemission experiments (2). Here we report that
superconductivity (Tc^~3K) can be induced in Bi2Te3 as-grown single crystal
(with hole-carriers) via pressure. The first-principles calculations show that
the electronic structure under pressure remains to be topologically nontrivial,
and the Dirac-type surface states can be well distinguished from bulk states at
corresponding Fermi level. The proximity effect between superconducting bulk
states and Dirac-type surface state could generate Majorana fermions on the
surface. We also discuss the possibility that the bulk state could be a
topological superconductor.
