Jump to content

Gapped Hamiltonian: Difference between revisions

From Wikipedia, the free encyclopedia
Content deleted Content added
upd
oops
Line 3: Line 3:
The property of being gapped or gapless is formally defined through a sequence of Hamiltonians on finite [[Lattice model (physics)|lattices]] in the [[thermodynamic limit]].<ref>{{Cite web|url=https://physics.stackexchange.com/questions/4930/what-does-it-mean-for-a-hamiltonian-or-system-to-be-gapped-or-gapless/29166|title=quantum mechanics - What does it mean for a Hamiltonian or system to be gapped or gapless?|website=Physics Stack Exchange|access-date=2019-02-02}}</ref>
The property of being gapped or gapless is formally defined through a sequence of Hamiltonians on finite [[Lattice model (physics)|lattices]] in the [[thermodynamic limit]].<ref>{{Cite web|url=https://physics.stackexchange.com/questions/4930/what-does-it-mean-for-a-hamiltonian-or-system-to-be-gapped-or-gapless/29166|title=quantum mechanics - What does it mean for a Hamiltonian or system to be gapped or gapless?|website=Physics Stack Exchange|access-date=2019-02-02}}</ref>


An example is the [[BSC theory|BSC Hamiltonian]] in the theory of superconductivity.
An example is the [[BCS theory|BCS Hamiltonian]] in the theory of superconductivity.


In [[quantum field theory]], a continuum limit of many-body physics, a gapped Hamiltonian induces a [[mass gap]].
In [[quantum field theory]], a continuum limit of many-body physics, a gapped Hamiltonian induces a [[mass gap]].

Revision as of 09:35, 2 February 2019

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.[1]

An example is the BCS Hamiltonian in the theory of superconductivity.

In quantum field theory, a continuum limit of many-body physics, a gapped Hamiltonian induces a mass gap.

References

  1. ^ "quantum mechanics - What does it mean for a Hamiltonian or system to be gapped or gapless?". Physics Stack Exchange. Retrieved 2019-02-02.