This material is based on research sponsored in part by the Defense Advanced Research Projects Agency (DARPA) through a Young Faculty Award under grant D23AP00174-00. The views and conclusions contained here are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, by DARPA, the Department of the Interior, or the US government. This work is supported by the Laboratory Directed Research and Development programme at Sandia National Laboratories, a multimission laboratory managed and operated by the National Technology and Engineering Solutions of Sandia, a wholly owned subsidiary of Honeywell International for the National Nuclear Security Administration of the US Department of Energy under contract DE-NA0003525. This work was performed, in part, at the Center for Integrated Nanotechnologies, an Office of Science User Facility, operated for the US Department of Energy Office of Science. This paper describes objective technical results and analysis. Any subjective views or opinions that might be expressed in the paper do not necessarily represent the views of the US Department of Energy or the US government.