  Using high-pressure magnetotransport techniques we have discovered
superconductivity in Bi2Te, a member of the infinitely adaptive (Bi2)m(Bi2Te3)n
series, whose end members, Bi and Bi2Te3, can be tuned to display topological
surface states or superconductivity. Bi2Te has a maximum Tc= 8.6 K at P= 14.5
GPa and goes through multiple high pressure phase transitions, ultimately
collapsing into a bcc structure that suggests a universal behavior across the
series. High-pressure magnetoresistance and Hall measurements suggest a
semi-metal to metal transition near 5.4 GPa, which accompanies the hexagonal to
intermediate phase transition seen via x-ray diffraction measurements. In
addition, the linearity of Hc2(T) exceeds the Werthamer-Helfand-Hohenberg
limit, even in the extreme spin-orbit scattering limit, yet is consistent with
other strong spin-orbit materials. Considering these results in combination
with similar reports on strong spin-orbit scattering materials seen in the
literature, we suggest the need for a new theory that can address the
unconventional nature of their superconducting states.
