Left-handed optical radiation torque
Language
en
Article de revue
This item was published in
Nature Photonics. 2014-08, vol. 8, n° 8, p. 610-614
Nature Publishing Group
English Abstract
Optical forces and torques are two mechanical degrees of freedom available to manipulate matter, and form the basis of optical tweezing strategies. In contrast to the Keplerian intuition that objects should be pushed ...Read more >
Optical forces and torques are two mechanical degrees of freedom available to manipulate matter, and form the basis of optical tweezing strategies. In contrast to the Keplerian intuition that objects should be pushed downstream an incident photon flux, the concept of 'negative' optical forces has recently been described and has triggered many developments. Here, we report on the counterintuitive angular analogue of negative optical forces by demonstrating that circularly polarized Gaussian light beams give rise to torque with opposite sign to that of the incident optical angular momentum. Such a 'left-handed' mechanical effect is demonstrated by the use of an inhomogeneous and anisotropic transparent macroscopic medium. Practical difficulties associated with the direct observation of optically induced spinning of a macroscopic object are circumvented via the rotational Doppler effect. These results shed light on spin-orbit optomechanics and equip the left-handed optomechanical toolbox with angular features.Read less <
ANR Project
Initiative d'excellence de l'Université de Bordeaux - ANR-10-IDEX-0003
Origin
Hal imported