Spatially structured photons that travel in free space slower than the speed of light

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21340%2F15%3A00226131" target="_blank" >RIV/68407700:21340/15:00226131 - isvavai.cz</a>

Výsledek na webu

<a href="http://www.sciencemag.org/content/347/6224/857.abstract" target="_blank" >http://www.sciencemag.org/content/347/6224/857.abstract</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1126/science.aaa3035" target="_blank" >10.1126/science.aaa3035</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Spatially structured photons that travel in free space slower than the speed of light

Popis výsledku v původním jazyce

That the speed of light in free space is constant is a cornerstone of modern physics. However, light beams have finite transverse size, which leads to a modification of their wave vectors resulting in a change to their phase and group velocities. We study the group velocity of single photons by measuring a change in their arrival time that results from changing the beam?s transverse spatial structure. Using time-correlated photon pairs, we show a reduction in the group velocity of photons in both a Bessel beam and photons in a focused Gaussian beam. In both cases, the delay is several micrometers over a propagation distance of ~1 meter. Our work highlights that, even in free space, the invariance of the speed of light only applies to plane waves.

Název v anglickém jazyce

Spatially structured photons that travel in free space slower than the speed of light

Popis výsledku anglicky

That the speed of light in free space is constant is a cornerstone of modern physics. However, light beams have finite transverse size, which leads to a modification of their wave vectors resulting in a change to their phase and group velocities. We study the group velocity of single photons by measuring a change in their arrival time that results from changing the beam?s transverse spatial structure. Using time-correlated photon pairs, we show a reduction in the group velocity of photons in both a Bessel beam and photons in a focused Gaussian beam. In both cases, the delay is several micrometers over a propagation distance of ~1 meter. Our work highlights that, even in free space, the invariance of the speed of light only applies to plane waves.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

BH - Optika, masery a lasery

OECD FORD obor

—

Projekt

—

Návaznosti

V - Vyzkumna aktivita podporovana z jinych verejnych zdroju

Rok uplatnění

2015

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

SCIENCE

ISSN

0036-8075

e-ISSN

—

Svazek periodika

347

Číslo periodika v rámci svazku

6224

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

4

Strana od-do

857-860

Kód UT WoS článku

000349761100039

EID výsledku v databázi Scopus

2-s2.0-84923241748