An early formulation by Stokes of the theories of the rotatory polarizations of light

AbstractThe two letters now communicated are from G. G. Stokes to W. Thomson, of dates Dec. 12–13, 1848, three years after Faraday's great magneto-optic discovery. They formulated already the permissible types for general equations of propagation, virtually on the basis of the very modern criterion of covariance,—relative to all changes of the spatial frame of reference in the case of active fluids, but having regard to the fixed direction of the extraneous magnetic field in the Faraday case. Their form was elucidated in each case by correlation with a remarkable and significant type of rotational stress in a propagating medium.

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Acting Rehearsal in Collaborative Multimodal Mixed Reality Environments

Presence Teleoperators & Virtual Environments ◽

10.1162/pres_a_00109 ◽

2012 ◽

Vol 21 (4) ◽

pp. 406-422 ◽

Cited By ~ 16

Author(s):

William Steptoe ◽

Jean-Marie Normand ◽

Oyewole Oyekoya ◽

Fabrizio Pece ◽

Elias Giannopoulos ◽

...

Keyword(s):

Facial Expression ◽

System Architecture ◽

Heterogeneous System ◽

Mixed Reality ◽

Frame Of Reference ◽

Telecommunication System ◽

Spatial Frame ◽

The Common ◽

Successes And Failures

This paper presents the use of our multimodal mixed reality telecommunication system to support remote acting rehearsal. The rehearsals involved two actors, located in London and Barcelona, and a director in another location in London. This triadic audiovisual telecommunication was performed in a spatial and multimodal collaborative mixed reality environment based on the “destination-visitor” paradigm, which we define and put into use. We detail our heterogeneous system architecture, which spans the three distributed and technologically asymmetric sites, and features a range of capture, display, and transmission technologies. The actors' and director's experience of rehearsing a scene via the system are then discussed, exploring successes and failures of this heterogeneous form of telecollaboration. Overall, the common spatial frame of reference presented by the system to all parties was highly conducive to theatrical acting and directing, allowing blocking, gross gesture, and unambiguous instruction to be issued. The relative inexpressivity of the actors' embodiments was identified as the central limitation of the telecommunication, meaning that moments relying on performing and reacting to consequential facial expression and subtle gesture were less successful.

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Active angular tuning and switching of Brewster quasi bound states in the continuum in magneto-optic metasurfaces

Nanophotonics ◽

10.1515/nanoph-2021-0412 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Diego R. Abujetas ◽

Nuno de Sousa ◽

Antonio García-Martín ◽

José M. Llorens ◽

José A. Sánchez-Gil

Keyword(s):

Magnetic Field ◽

Magnetic Dipole ◽

Bound States ◽

Electromagnetic Spectrum ◽

Resonant Modes ◽

Out Of Plane ◽

Q Factors ◽

The Impact ◽

The Continuum ◽

Magneto Optic

Abstract Bound states in the continuum (BICs) emerge throughout physics as leaky/resonant modes that remain, however, highly localized. They have attracted much attention in photonics, and especially in metasurfaces. One of their most outstanding features is their divergent Q-factors, indeed arbitrarily large upon approaching the BIC condition (quasi-BICs). Here, we investigate how to tune quasi-BICs in magneto-optic (MO) all-dielectric metasurfaces. The impact of the applied magnetic field in the BIC parameter space is revealed for a metasurface consisting of lossless semiconductor spheres with MO response. Through our coupled electric/magnetic dipole formulation, the MO activity is found to manifest itself through the interference of the out-of-plane electric/magnetic dipole resonances with the (MO-induced) in-plane magnetic/electric dipole, leading to a rich, magnetically tuned quasi-BIC phenomenology, resembling the behavior of Brewster quasi-BICs for tilted vertical-dipole resonant metasurfaces. Such resemblance underlies our proposed design for a fast MO switch of a Brewster quasi-BIC by simply reversing the driving magnetic field. This MO-active BIC behavior is further confirmed in the optical regime for a realistic Bi:YIG nanodisk metasurface through numerical calculations. Our results present various mechanisms to magneto-optically manipulate BICs and quasi-BICs, which could be exploited throughout the electromagnetic spectrum with applications in lasing, filtering, and sensing.

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