Editing Quasiparticle (section)

==Common examples ==
{{See also|List of quasiparticles}}
This section contains most common examples of quasiparticles and collective excitations. 

*In solids, an electron quasiparticle is an [[electron]] as affected by the other forces and interactions in the solid. The electron quasiparticle has the same [[electric charge|charge]] and [[Spin (physics)|spin]] as a "normal" ([[elementary particle]]) electron, and like a normal electron, it is a [[fermion]]. However, its mass can differ substantially from that of a normal electron; see the article [[effective mass (solid-state physics)|effective mass]].<ref name="Kaxiras">{{cite book |author=Kaxiras |first=Efthimios |url=https://books.google.com/books?id=WTL_vgbWpHEC&pg=PA65 |title=Atomic and Electronic Structure of Solids |date=9 January 2003 |publisher=Cambridge University Press |isbn=978-0-521-52339-4 |pages=65–69 |language=en}}</ref> Its electric field is also modified, as a result of [[electric field screening]]. In many other respects, especially in metals under ordinary conditions, these so-called Landau quasiparticles{{Citation needed|date=August 2008}} closely resemble familiar electrons; as [[Michael F. Crommie|Crommie's]] "[[quantum corral]]" showed, an [[Scanning tunneling microscope|STM]] can image their [[interference (wave propagation)|interference]] upon scattering.
*A [[electron hole|hole]] is a quasiparticle consisting of the lack of an electron in a state; it is most commonly used in the context of empty states in the [[valence band]] of a [[semiconductor]].<ref name="Kaxiras"/> A hole has the opposite charge of an electron.
*A [[phonon]] is a collective excitation associated with the vibration of atoms in a rigid [[crystal structure]]. It is a [[quantum]] of a [[sound wave]].<ref>{{Cite book |last=Wilczek |first=Frank |title=Fundalmentals : Ten Keys to Reality |date=2021 |publisher=Penguin Press |isbn=9780735223790 |location=New York, New York |page=88 |language=en-us |lccn=2020020086}}</ref>
*A [[magnon]] is a collective excitation<ref name=Kaxiras/> associated with the electrons' spin structure in a crystal lattice. It is a quantum of a [[spin wave]].
*In materials, a photon quasiparticle is a [[photon]] as affected by its interactions with the material. In particular, the photon quasiparticle has a modified relation between wavelength and energy ([[dispersion relation]]), as described by the material's [[index of refraction]]. It may also be termed a [[polariton]], especially near a resonance of the material. For example, an [[exciton-polariton]] is a superposition of an exciton and a photon; a [[Phonon polariton|phonon-polariton]] is a superposition of a phonon and a photon.
*A [[plasmon]] is a collective excitation, which is the quantum of [[plasma oscillation]]s (wherein all the electrons simultaneously oscillate with respect to all the ions).
*A [[polaron]] is a quasiparticle which comes about when an electron interacts with the [[polarization density|polarization]] of its surrounding ions.
*An [[exciton]] is an electron and hole bound together.