quasiparticle

https://doi.org/10.1351/goldbook.08863
Discrete disorder in a multi-particulate system that exhibits particle-specific behavior and properties.
Notes:
  1. A real particle can exist by itself, out of other real particles, while a quasiparticle cannot. It exists only within a multi-particulate system, like a gas bubble inside water or beer. It looks and behaves like a particle, but it does not exist outside liquid. Such a bubble is a macroscopic quasiparticle.
  2. Characteristics typical of particles, such as the mass (referred to as effective mass), momentum, energy, velocity, mobility and ability to undergo collisions can be assigned to quasiparticles.
  3. Examples of quasiparticles related to electromagnetic field responsive materials are electron hole, exciton, magnon, phonon, plasmon, polaron and soliton.
  4. There are two main classes of quasiparticles:
    1. those of the excitation type whose motion corresponds to a motion of individual particles interacting with other parts of the system; examples are exciton, hole, soliton and polaron;
    2. those that originate from a synchronized collective motion of the whole system, referred to as collective excitations or collective modes; examples are magnon, plasmon and phonon.
Source:
PAC, 2022, 94, 15. (Glossary of terms relating to electronic, photonic and magnetic properties of polymers (IUPAC Recommendations 2021)) on page 44 [Terms] [Paper]