Towards understanding two-level-systems in amorphous solids: insights from quantum circuits

@article{Mller2017TowardsUT,
  title={Towards understanding two-level-systems in amorphous solids: insights from quantum circuits},
  author={Clemens M{\"u}ller and Jared H. Cole and J{\"u}rgen Lisenfeld},
  journal={Reports on Progress in Physics},
  year={2017},
  volume={82}
}
Amorphous solids show surprisingly universal behaviour at low temperatures. The prevailing wisdom is that this can be explained by the existence of two-state defects within the material. The so-called standard tunneling model has become the established framework to explain these results, yet it still leaves the central question essentially unanswered—what are these two-level defects (TLS)? This question has recently taken on a new urgency with the rise of superconducting circuits in quantum… 

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