Mechanism of angular momentum transfer from microwaves to a copper ring
2016 (English)In: European Physical Journal D: Atomic, Molecular and Optical Physics, ISSN 1434-6060, E-ISSN 1434-6079, Vol. 70, no 8, 172Article in journal (Refereed) Published
In the exchange of orbital angular momentum between an electromagnetic wave and a copper ring we examine the origin of the Angular Momentum. We then investigate the transfer mechanism between the microwave and the object, and compare it with other mechanisms. We evidence a transfer mechanism based on the reflection of the electromagnetic field on the copper ring. In particular, at a microscopic scale, we show that the electromagnetic field induces alternative electric currents in the ring, with a small drift. Although little, the resistivity of copper leads to a force that rotates the ring. The estimation of the torque, which is of the order of 10(-8) Nm, is in good agreement with the experimental measurements. We also show that the transfer of electromagnetic orbital angular momentum to objects could be a way to measure the orbital angular momentum carried by electromagnetic fields, and we discuss possible applications.
Place, publisher, year, edition, pages
2016. Vol. 70, no 8, 172
Fusion, Plasma and Space Physics
IdentifiersURN: urn:nbn:se:uu:diva-307876DOI: 10.1140/epjd/e2016-70193-6ISI: 000382741600011OAI: oai:DiVA.org:uu-307876DiVA: diva2:1048843