The ‘Higgs’ amplitude mode at the two-dimensional superfluid/Mott insulator transition

@article{Endres2012TheA,
  title={The ‘Higgs’ amplitude mode at the two-dimensional superfluid/Mott insulator transition},
  author={M. Endres and Takeshi Fukuhara and David Pekker and Marc Cheneau and Peter Schau$\beta$ and Christian Gross and Eugene A. Demler and Stefan Kuhr and Immanuel Bloch},
  journal={Nature},
  year={2012},
  volume={487},
  pages={454-458}
}
Spontaneous symmetry breaking plays a key role in our understanding of nature. In relativistic quantum field theory, a broken continuous symmetry leads to the emergence of two types of fundamental excitation: massless Nambu–Goldstone modes and a massive ‘Higgs’ amplitude mode. An excitation of Higgs type is of crucial importance in the standard model of elementary particle physics, and also appears as a fundamental collective mode in quantum many-body systems. Whether such a mode exists in low… 
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