- Source: Gapped Hamiltonian
In many-body physics, most commonly within condensed-matter physics, a gapped Hamiltonian is a Hamiltonian for an infinitely large many-body system where there is a finite energy gap separating the (possibly degenerate) ground space from the first excited states. A Hamiltonian that is not gapped is called gapless.
The property of being gapped or gapless is formally defined through a sequence of Hamiltonians on finite lattices in the thermodynamic limit.
An example is the BCS Hamiltonian in the theory of superconductivity.
In quantum many-body systems, ground states of gapped Hamiltonians have exponential decay of correlations.
In quantum field theory, a continuum limit of many-body physics, a gapped Hamiltonian induces a mass gap.
References
Kata Kunci Pencarian:
- Gapped Hamiltonian
- Spectral gap (physics)
- Mass gap
- Yang–Mills existence and mass gap
- Bose–Hubbard model
- Kitaev chain
- Periodic table of topological insulators and topological superconductors
- Transverse-field Ising model
- Topological degeneracy
- Symmetry-protected topological order
