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arXiv · 1410.5108

Are there quantum oscillations in an incommensurate charge density wave?

Yi Zhang·Akash V. Maharaj·Steven A. Kivelson
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Abstract

Because a material with an incommensurate charge density wave (ICDW) is only quasi-periodic, 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 quasi-crystal, no quantum oscillations survive at all. Rational and irrational numbers really are different.

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Yi Zhang, Akash V. Maharaj, Steven A. Kivelson. 2015-02-06. Are there quantum oscillations in an incommensurate charge density wave?. https://doi.org/10.1103/physrevb.91.085105

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