Subluminal and superluminal velocities of free-space photons
DOI (Low Temperature Physics):
https://doi.org/10.1063/10.0044812Ключові слова:
free-space photons, wave packets, group velocity, phase velocityАнотація
Розглянуто прямолінійне поширення електромагнітних хвильових пакетів у вільному просторі, використовуючи теорію електромагнітного поля, скалярне поширення хвильових пакетів та квантово-механічний формалізм. Показано, що просторово локалізовані хвильові пакети за своєю природою характеризуються субсвітловою груповою швидкістю та надсвітловою фазовою швидкістю, добуток яких дорівнює с2. Ці швидкості також відомі як «енергетична» та «імпульсна» швидкості, запроваджені К. Мілтоном та Дж. Швінгером. Наведено загальні висновки за допомогою явних обчислень для гаусових та більш високих порядків пучків та хвильових пакетів, а також підкреслено тонкощі квантово-механічного опису, заснованого на «хвильовій функції фотона».
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