News and events

News and events

Current events QSciTech


This week's QSciTech speaker is Marco Ornigotti from University of Rostock.

Location: Multipurpose room
Time: Thursday 21 September at 12pm
Speaker: Dr Marco Ornigotti
Title: On the separation of the angular momentum of light for optical beams
Abstract: Traditionally, the angular momentum of light is calculated for “bullet-like” electromagnetic wave packets, although in actual optical experiments “pencil-like” beams of light are more commonly used. The fact that a wave packet is bounded transversely and longitudinally while a beam has, in principle, an infinite extent along the direction of propagation, renders incomplete the textbook calculation of the spin/orbital separation of the angular momentum of a light beam. In this lecture,  I will show that a novel,  extra surface part must be added in order to preserve the gauge invariance of the optical angular momentum per unit length. The impact of this extra term is quantified by means of two examples: a Laguerre-Gaussian and a Bessel beam, both circularly polarized.

QSciTech journal club:

Time: currently in preparation 

Location: Multipurpose room E6B 2.300.

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