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Ring quantum cascade lasers with twisted wavefronts.

ABSTRACT: We demonstrate the on-chip generation of twisted light beams from ring quantum cascade lasers. A monolithic gradient index metamaterial is fabricated directly into the substrate side of the semiconductor chip and induces a twist of the light's wavefront. This significantly influences the obtained beam pattern, which changes from a central intensity minimum to a maximum depending on the discontinuity count of the metamaterial. Our design principle provides an interesting alternative to recent implementations of microlasers operating at an exceptional point.

SUBMITTER: Szedlak R

PROVIDER: S-EPMC5964118 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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Ring quantum cascade lasers with twisted wavefronts.

Szedlak Rolf R Hisch Thomas T Schwarz Benedikt B Holzbauer Martin M MacFarland Donald D Zederbauer Tobias T Detz Hermann H Andrews Aaron Maxwell AM Schrenk Werner W Rotter Stefan S Strasser Gottfried G

Scientific reports 20180522 1

We demonstrate the on-chip generation of twisted light beams from ring quantum cascade lasers. A monolithic gradient index metamaterial is fabricated directly into the substrate side of the semiconductor chip and induces a twist of the light's wavefront. This significantly influences the obtained beam pattern, which changes from a central intensity minimum to a maximum depending on the discontinuity count of the metamaterial. Our design principle provides an interesting alternative to recent imp ...[more]

PMID: 29789653

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