The topological insulating materials offer conductive surface states
that can be useful for quantum computing, catalysis, and other
applications. In this recent work, we (Young, Chowdhury, Walter, Mele,
Kane, and Rappe, under review, 2011) show that compressing the material
strengthens the topological insulating state, while expanding the
material eventually takes this behavior away completely. Using external
pressure as a control parameter suggests general ways to strengthen
this important physical effect.