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Published on: September 25, 2020
Coherence Switching with Metamaterials
Matias Koivurova1,2, Tommi K Hakala3, Jari Turunen3
1Tampere University, Faculty of Engineering and Natural Sciences, 33720 Tampere, Finland.
Abstract:
We demonstrate, theoretically, how the insertion of an enhanced epsilon-near-zero (EENZ) mirror in a laser cavity grants exceptional control over the coherence properties of the emitted light beam. By exploiting the peculiar sensitivity to polarization of EENZ materials, we achieve superior control over the spatial coherence of the emitted laser light, which can be switched at will between nearly incoherent and fully coherent, solely by means of polarization optics. Our EENZ cavity design is expected to be an efficient, compact, reconfigurable, and easily scalable source of light for illumination and speckle contrast imaging, as well as any other application that benefits from controlled spatial coherence.
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