ABSTRACT Phase locking of an array of lasers is a highly effective method in beam shaping because it increases the output power and reduces the lasing threshold. Here, we show a conceptually

novel phase-locking mechanism based on ‘antenna mutual coupling’ in which laser elements interact through far-field radiations with definite phase relations. This allows a long-range global

coupling among the array elements to achieve a robust phase locking in two-dimensional laser arrays. The scheme is ideal for lasers with a deep subwavelength confined cavity, such as

nanolasers, whose divergent beam patterns could be used to achieve a strong coupling among the elements in the array. We demonstrated experimentally such a scheme based on subwavelength

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MULTIFUNCTIONAL WIDE-ANGLE OPTICS AND LASING BASED ON SUPERCELL METASURFACES Article Open access 18 June 2021 ON-DEMAND GENERATION OF NONDIFFRACTING HELMHOLTZ–GAUSS LASER BEAMS Article Open

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  Download references ACKNOWLEDGEMENTS This work is supported by the National Aeronautics and Space Administration and National Science Foundation, and also performed at the Center for

Integrated Nanotechnologies, a US Department of Energy, Office of Basic Energy Sciences user facility. Sandia National Laboratories is a multiprogram laboratory operated by Sandia

Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department of Electrical Engineering and Computer Science and Research Laboratory of Electronics, Massachusetts Institute of Technology,

Cambridge, 02139, Massachusetts, USA Tsung-Yu Kao & Qing Hu * LongWave Photonics LLC, Mountain View, 94043, California, USA Tsung-Yu Kao * Sandia National Laboratories, Center of

Integrated Nanotechnologies, MS 1303, Albuquerque, 87185-130, New Mexico, USA John L. Reno Authors * Tsung-Yu Kao View author publications You can also search for this author inPubMed Google

Scholar * John L. Reno View author publications You can also search for this author inPubMed Google Scholar * Qing Hu View author publications You can also search for this author inPubMed 

Google Scholar CONTRIBUTIONS T.-Y.K. conceived the strategy, designed and fabricated the antenna mutual coupled laser arrays and performed the measurements and analysis, and J.L.R. provided

the material growth. All the work was done under the supervision of Q.H. CORRESPONDING AUTHOR Correspondence to Qing Hu. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no

competing financial interests. SUPPLEMENTARY INFORMATION SUPPLEMENTARY INFORMATION Supplementary information (PDF 918 kb) RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE

CITE THIS ARTICLE Kao, TY., Reno, J. & Hu, Q. Phase-locked laser arrays through global antenna mutual coupling. _Nature Photon_ 10, 541–546 (2016).

https://doi.org/10.1038/nphoton.2016.104 Download citation * Received: 18 December 2015 * Accepted: 27 April 2016 * Published: 13 June 2016 * Issue Date: August 2016 * DOI:

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