Research output: Contribution to journal › Article › peer-review
Grigorii S. Sokolovskii, Vasileia Melissinaki, Ksenia A. Fedorova, Vladislavv Dudelev, Sergey N. Losev, Vladislav E. Bougrov, Wilson Sibbett, Maria Farsari, Edik U. Rafailov
Multimode high-power laser diodes suffer from inefficient beam focusing, leading to a focal spot 10-100 times greater than the diffraction limit. This inevitably restricts their wider use in 'direct-diode' applications in materials processing and biomedical photonics. We report here a 'super-focusing' characteristic for laser diodes, where the exploitation of self-interference of modes enables a significant reduction of the focal spot size. This is achieved by employing a conical microlens fabricated on the tip of a multimode optical fibre using 3D laser nano-printing (also known as multi-photon lithography). When refracted by the conical surface, the modes of the fibre-coupled laser beam self-interfere and form an elongated narrow focus, usually referred to as a 'needle' beam. The multiphoton lithography technique allows the realisation of almost any optical element on a fibre tip, thus providing the most suitable interface for free-space applications of multimode fibre-delivered laser beams. In addition, we demonstrate the optical trapping of microscopic objects with a super-focused multimode laser diode beam thus rising new opportunities within the applications sector where lab-on-chip configurations can be exploited. Most importantly, the demonstrated super-focusing approach opens up new avenues for the 'direct-diode' applications in material processing and 3D printing, where both high power and tight focusing is required.
Original language | English |
---|---|
Article number | 14618 |
Number of pages | 9 |
Journal | Scientific Reports |
Volume | 8 |
DOIs | |
Publication status | Published - 2 Oct 2018 |
Discover related content
Find related publications, people, projects and more using interactive charts.
Research output: Contribution to journal › Article › peer-review
Research output: Contribution to journal › Article › peer-review
Research output: Chapter in Book/Report/Conference proceeding › Conference contribution
Research output: Contribution to journal › Article › peer-review
Research output: Contribution to journal › Article › peer-review
Research output: Contribution to journal › Article › peer-review
Research output: Contribution to journal › Article › peer-review
Research output: Contribution to journal › Article › peer-review
Research output: Contribution to journal › Article › peer-review
Research output: Contribution to journal › Article › peer-review
Matt Carter (Reviewer)
Activity: Publication peer-review and editorial work types › Peer review of manuscripts
Manon Karin Schweinfurth (Member of editorial board)
Activity: Publication peer-review and editorial work types › Editor of research journal
Alan J. Stewart (Member of editorial board)
Activity: Publication peer-review and editorial work types › Editor of research journal
Matt Carter (Reviewer)
Activity: Publication peer-review and editorial work types › Peer review of manuscripts
Monica Arso Civil (Reviewer)
Activity: Publication peer-review and editorial work types › Peer review of manuscripts
ID: 256214141