Summary
Although the second-order coherence properties of a wide variety of optical fields have been investigated, the second-order coherence properties of fermion sources have been largely unexplored. In view of recent experimental proposals for novel extensions to fermionic systems of Hanbury Brown-Twiss-type experiments, it is important to understand better the coherence properties of fermion sources. In this paper a detailed study of the second-order temporal and spatial coherence of thermal electrons is made. Important distinctions between the coherence properties of thermal electrons and black-body radiation are pointed out. These distinctions arise from three principal considerations:a) particle number conservation,b) tensorial character of the basic fields,c) quantum statistics.
Riassunto
Sebbene siano state studiate le proprietà di coerenza di secondo ordine di una grande varietà di campi ottici, le proprietà di coerenza di second’ordine delle sorgenti fermioniche sono state poco esaminate. In vista delle recenti proposte sperimentali per nuove estensioni ai sistemi fermionici degli esperimenti del tipo di Hanbury Brown-Twiss, è importante capire meglio le proprictà di coerenza delle fonti fermioniche. In questo articolo, si fa uno studio dettagliato della coerenza temporale e spaziale di second’ordine degli elettroni termici. Si sottolineano importanti distinzioni tra le proprietà di coerenza degli elettroni termici e la radiazione di un corpo nero. Queste distinzioni sorgono da 3 considerazioni principali:a) conservazione del numero di particelle,b) carattere tensoriale dei campi di base,c) statistica quantistica.
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References
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Silverman, M.P. Second-order temporal and spatial coherence of thermal electrons. Nuovo Cim B 99, 227–245 (1987). https://doi.org/10.1007/BF02726584
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DOI: https://doi.org/10.1007/BF02726584