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Energy Level diagram for n- 2 level atoms. Interaction with Radiation field. Radiation from an Extended Sample. Raise Energy level. Destroy photon. By some sort of change in basis:. Radiation from an Extended Sample. “Spin” operators are the same as before.
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Interaction with Radiation field Radiation from an Extended Sample Raise Energy level Destroy photon
By some sort of change in basis: Radiation from an Extended Sample
“Spin” operators are the same as before Absorption or emission of a photon with momentum k, Radiation Rate in k direction:
Non-linear Rayleigh scattering/superradiance Collective scattering: Dicke superradiance Rayleigh: Inouye et al., Science (1998)
Non-linear Rayleigh scattering/superradiance Recoiling atoms interfere with stationary atoms to form a diffraction grating, which then enhances scattering into that mode The Scattered Power
Non-linear Rayleigh scattering/superradiance Dipolar emission pattern radiates weakly along polarization axis, collective scattering is stronger along long axis I ~ 1-100mW/cm^2 t~ 50 ms Normal decay of atoms Superradiant decay of atoms
References Coherence in Spontaneous Radiation Processes Dicke, Phys. Rev. 93 1 99 (1954) Superradiant Rayliegh Scattering from a Bose Einstein Condensate S. Inouye, Science, 285 571 (1999) Cargese lecture notes W. Ketterle and S. Inouye: Collective enhancement and suppression in Bose-Einstein condensates. Compte rendus de l'académie des sciences, Série IV - Physique Astrophysique, vol. 2, pp. 339-380 (2001); e-print cond- mat/0101424.