2011-2014 Simons Foundation Postdoctoral Fellow
Condensed Matter Physics
411A Jadwin Hall
My research focuses on the study of topological phenomena in condensed matter physics, with an emphasis on topological insulators. Topological insulators are recently discovered states of quantum matter which are topologically distinct from conventional insulators such as diamond or silicon. Topological insulators are characterized by a bulk energy gap, just like conventional insulators, but support gapless surface modes that are largely insensitive to perturbations such as nonmagnetic disorder. The stability of these surface modes is protected by a bulk topological invariant which describes certain quantized electromagnetic response properties of the system, just as the stability of the chiral edge modes in a quantum Hall liquid is protected by a nonzero topological Chern number which describes the quantized Hall conductance. Most recently, I have been studying the effect of magnetic impurities and electron-electron interactions on topological insulators, experimental probes of the quantized electromagnetic response properties mentioned earlier, as well as fractional generalizations of topological insulators..
- Kondo effect in the helical edge liquid of the quantum spin Hall state
- J. Maciejko, C. X. Liu, Y. Oreg, X. L. Qi, C. Wu, S. C. Zhang, Phys. Rev. Lett. 102, 256803 (2009).
- Nonlocal edge state transport in the quantum spin Hall state
- A. Roth, C. Brüne, H. Buhmann, L. W. Molenkamp, J. Maciejko, X. L. Qi, S. C. Zhang, Science 325, 294 (2009).
- Topological quantization in units of the fine structure constant
- J. Maciejko, X. L. Qi, H. D. Drew, S. C. Zhang, Phys. Rev. Lett. 105, 166803 (2010).
- Fractional topological insulators in three dimensions
- J. Maciejko, X. L. Qi, A. Karch, S. C. Zhang, Phys. Rev. Lett. 105, 246809 (2010).