The Higgs mode is a ubiquitous collective excitation in relativistic systems with broken continuous symmetry. It is expected to appear in antiferromagnets, short coherence length superconductors, charge density waves, and superfluids near the Mott transition. Detection of the mode is a valuable test of the underlying field theory, and its mass gap is a measure of proximity to a quantum critical point. However, since the Higgs mode can decay into low energy Goldstone modes, its experimental visibility has been questioned. I will show that the visibility depends on the symmetry of the measured susceptibility. Furthermore, I will show that the Higgs peak survives even in the proximity of the strong coupling quantum critical point in two dimensions.
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