Leviton (quasiparticle)

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A leviton is a collective excitation of a single electron within a metal. [1] [2] [3] [4] It has been mostly studied in two-dimensional electron gases alongside quantum point contacts. The main feature is that the excitation produces an electron pulse without the creation of electron holes. The time-dependence of the pulse is described by a Lorentzian distribution created by a pulsed electric potential. [1] [2]

Levitons have also been described in graphene. [5] [6]

The leviton is named after Leonid Levitov, who first predicted its existence in 1996. [1]

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References

  1. 1 2 3 "New 'leviton' quasiparticle spotted by physicists". physicsworld.com. 24 October 2013. Retrieved 2013-11-27.
  2. 1 2 Dubois, J.; Jullien, T.; Portier, F.; Roche, P.; Cavanna, A.; Jin, Y.; Wegscheider, W.; Roulleau, P.; Glattli, D. C. (31 October 2013). "Minimal-excitation states for electron quantum optics using levitons" (PDF). Nature. 502 (7473): 659–663. Bibcode:2013Natur.502..659D. doi:10.1038/nature12713. PMID   24153178. S2CID   4459552.
  3. "Researchers produce the first experimental pulse-generation of a single electron—a leviton". Phys.org. Retrieved 2013-11-27.
  4. Francis, Matthew (2013-10-23). "New type of quantum excitation behaves like a solitary particle". Ars Technica. Retrieved 2023-03-14.
  5. Forrester, Derek Michael; Kusmartsev, Feodor V. (May 13, 2014). "Graphene levitons and anti-levitons in magnetic fields". Nanoscale. 6 (13): 7594–7603. Bibcode:2014Nanos...6.7594F. doi: 10.1039/C4NR00754A . PMID   24893578.
  6. Forrester, Derek Michael (1 January 2015). "Confinement effects of levitons in a graphene cosmology laboratory" (PDF). RSC Advances. 5 (7): 5442–5449. doi: 10.1039/C4RA11227J .