Year: 2024
Type: article
Abstract: A review of recent advances in spacetime optics is given, with special emphasis on time-refraction. This is a basic optical process, occurring at a temporal discontinuity or temporal boundary, that is able to produce various different effects, such as frequency shifts, energy amplification, time-reflection and photon emission. If, instead of a single discontinuity, we have two reverse temporal boundaries, we can form a temporal beam-splitter, where temporal interferences can occur. It will also be shown that, in the presence of an axis of symmetry, such as a magnetic field, the temporal beam-splitter can induce a rotation of the initial polarization state, similar to a Faraday rotation. Recent work on time-crystals, superluminal fronts and superfluid light will be reviewed. Time-gates, based on spacetime optical effects will be discussed. We also mention recent work on optical metamaterials. Finally, the quantum properties of time-refraction, which imply the emission of photon from vacuum, are considered, while similar problems in high energy QED associated with electron-positron pairs are briefly mentioned.
Source: Symmetry
DOI: 10.3390/sym16111548
Author: José Tito Mendonça
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,728
OpenAlex ID: W4404499710