"Disruption of quantum oscillations by an incommensurate charge density wave"

Yi Zhang: Akash V. Maharaj, and Steven Kivelson; Phys. Rev. B 91, 02/09/2015.

Additional Authors: Akash V. Maharaj, and Steven Kivelson

Abstract:

Because a material with an incommensurate charge density wave (ICDW) is only quasiperiodic, Bloch’s theorem does not apply and there is no sharply defined Fermi surface. We will show that, as a consequence, there are no quantum oscillations which are truly periodic functions of 1/B (where B is the magnitude of an applied magnetic field). For a weak ICDW, there exist broad ranges of 1/B in which approximately periodic variations occur, but with frequencies that vary inexorably in an unending cascade with increasing 1/B . For a strong ICDW, e.g., in a quasicrystal, no quantum oscillations survive at all. Rational and irrational numbers really are different.