Summary
The theory of Weisskopf and Wigner is estended to describe the modifications of spontaneous emission which occur when atoms or molecules emit radiation spontaneously, while simultaneously undergoing stimulated emissions or absorptions. The theory is developed generally for radiation present initially at or off resonance. It is illustrated for the simple case that decay quanta are emitted spontaneously parallel or antiparallel to the direction of propagation of radiation causing stimulated transitions. Spectral-line profiles calculated for this case are shown in appropriate limits to agree with the results of previous theories and experiment. General theoretical procedures and explicit expressions are developed for a variety of more complex situations which might reasonably be encountered in future experiments.
Riassunto
Si estende la teoria di Weisskopf e Wigner in modo da descrivere le modificazioni dell’emissione spontanea che hanno luogo quando atomi o molecole emettono spontaneamente radiazione mentre contemporancamente subiscono spontaneamente emissioni od assorbimenti stimolati. Si sviluppa la teoria in generale per la radiazione presente inizialmente alla o fuori della risonanza. La si illustra per il semplice caso in cui quanti di decadimento sono emessi spontaneamente parallelamente o antiparallelamente alla direzione di propagazione della radiazione che causa le transizioni stimolate. Si dimostra che i profili delle righe spettrali calcolati in questo caso concordano, entro limiti appropriati, con i risultati delle precedenti teorie e degli esperimenti. Si sviluppano procedimenti teorici generali ed espressioni esplicite per una varietà di situazioni più complesse che potrebbero ragionevolmente presentarsi in futuri esperimenti.
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References
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Based on a dissertation submitted to the faculty of the University of Maryland in 1968 by R. Bose in partial fulfilment of the requirements for the Ph.D. degree. The principal conclusions of this investigation were presented at the Boston meeting of the American Physical Society,Bull. Am. Phys. Soc.,13, 172 (1968).
Work at Maryland supported by Advanced Research Projects Agency (SD-101), National Aeronautics and Space Administration (NGR 21-002-022), and Army Research Office, Durham (DAHCO 4-67-C0023).
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Bose, R., White, J.A. A quantum theory of spontaneous emission in the presence of external radiation. Nuov Cim B 5, 11–20 (1971). https://doi.org/10.1007/BF02737705
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DOI: https://doi.org/10.1007/BF02737705