High pressure differential conductance measurements of (Pb,Sn)Se

Topological transitions have been recognized as a new type of quantum phase transition.  Recently, a number of papers have reported scanning tunneling microscope (STM) measurements of the Landau level spectra of topologically non-trivial materials.  Such measurements can offer substantial insight into the nature of the transition between topologically distinct phases.  Although applied pressure represents an attractive means to drive a topological quantum phase transition, STM measurements can not be performed under high pressure conditions.  In this talk, I will discuss our recent attempts to observe Landau level spectra in compressed (Pb,Sn)Se using differential conductance measurements. \\* \\* Acknowledgements: TAP supported by REU NSF DMR-1461019. Pressure cell development and measurements at high magnetic fields supported by the National High Magnetic Field Laboratory User Collaboration Grants Program.  Synthesis, characterization, and high pressure measurements supported by NSF DMR-1453752.