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Lasing without inversion

In laser science, lasing without inversion (LWI), or lasing without population inversion, is a technique used for laser beam generation without the requirement of population inversion. A laser working under this scheme exploits the quantum interference between the probability amplitudes of atomic transitions in order to eliminate absorption without disturbing the stimulated emission. This phenomenon is also the essence of electromagnetically induced transparency.

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In laser science, lasing without inversion (LWI),1 or lasing without population inversion, is a technique used for laser beam generation without the requirement of population inversion.2 A laser working under this scheme exploits the quantum interference between the probability amplitudes of atomic transitions in order to eliminate absorption without disturbing the stimulated emission.3 This phenomenon is also the essence of electromagnetically induced transparency.4

The basic LWI concept was first predicted by Ali Javan in 1956.56 The first demonstration of LWI was carried out by Marlan Scully in an experiment in rubidium and sodium at Texas A&M University, and then at NIST in Boulder, Colorado.7

References

References

  1. Marvin J. Weber. Handbook of Lasers. CRC Press. 2019. p. 1151. ISBN 978-1-4200-5017-2.
  2. Harris, S. E. (1989). "Lasers without inversion: Interference of lifetime-broadened resonances". Physical Review Letters. 62 (9): 1033–1036. Bibcode:1989PhRvL..62.1033H. doi:10.1103/PhysRevLett.62.1033. PMID 10040407.
  3. Mompart, J.; Corbalán, R. (2000). "Lasing without inversion" (PDF). J. Opt. B. 2 (3): R7–R24. Bibcode:2000JOptB...2R...7M. doi:10.1088/1464-4266/2/3/201. S2CID 121209763. Archived from the original (PDF) on 2020-01-01.
  4. Scully, M., & Zubairy, M. (1997). Chapter 7. In Quantum optics (p. 220). Cambridge: Cambridge University Press.
  5. Scully, M., & Zubairy, M. (1997). Chapter 7. In Quantum optics (p. 245). Cambridge: Cambridge University Press.
  6. A. Javan, Phys. Rev. 107, 1579 (1956)
  7. Javan, A. (2000). "On knowing Marlan". In Ode to a quantum physicist: A festschrift in honor of Marlan O. Scully. Elsevier.