{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,18]],"date-time":"2025-12-18T14:20:38Z","timestamp":1766067638354,"version":"build-2065373602"},"reference-count":52,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2022,10,4]],"date-time":"2022-10-04T00:00:00Z","timestamp":1664841600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Science and Technology Foundation of Portuguese Ministry of Science, Technology and Higher Education (FCT\u2014MCTES)","doi-asserted-by":"publisher","award":["UID\/FIS\/00068\/2020","EXPL\/FIS-OTI\/0332\/2021"],"award-info":[{"award-number":["UID\/FIS\/00068\/2020","EXPL\/FIS-OTI\/0332\/2021"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>We report a significant numerical improvement in multi-rod laser efficiency, with an enhanced solar tracking error compensation capacity for a heliostat-parabolic system. The solar laser head was composed of a fused silica conical lens and a single conical pump cavity ensuring multiple passes through four 4.55 mm diameter, 15 mm length Nd:YAG rods. 0.76\u00b0 tracking error width at 10% laser power loss, and total multimode laser power variation of 0.05% at \u00b10.1\u00b0 solar tracking error and 0.30% at \u00b10.2\u00b0 solar tracking error were numerically calculated, being 1.27, 74.80 and 21.63 times, respectively, more than the experimental record in solar tracking error compensation capacity attained with a dual-rod side-pumping horizontal prototype pumped by the same heliostat-parabolic system. Additionally, the end-side-pumping configuration of the four-rod solar laser-enabled 43.7 W total multimode solar laser power, leading to 24.7 W\/m2 collection efficiency and 2.6% solar-to-laser power conversion efficiency, being 1.75 and 1.44 times, respectively, more than that experimentally obtained from the dual-rod side-pumping prototype. The significant improvement in solar tracking error compensation capacity with a highly efficient end-side-pumping configuration is meaningful because it reduces the cost of high-precision trackers for solar laser applications.<\/jats:p>","DOI":"10.3390\/mi13101670","type":"journal-article","created":{"date-parts":[[2022,10,9]],"date-time":"2022-10-09T04:00:02Z","timestamp":1665288002000},"page":"1670","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Highly Efficient Four-Rod Pumping Approach for the Most Stable Solar Laser Emission"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2888-718X","authenticated-orcid":false,"given":"Miguel","family":"Catela","sequence":"first","affiliation":[{"name":"Center of Physics and Technological Research (CEFITEC), Department of Physics, Faculty of Science and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4406-4108","authenticated-orcid":false,"given":"Dawei","family":"Liang","sequence":"additional","affiliation":[{"name":"Center of Physics and Technological Research (CEFITEC), Department of Physics, Faculty of Science and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal"}]},{"given":"Cl\u00e1udia R.","family":"Vistas","sequence":"additional","affiliation":[{"name":"Center of Physics and Technological Research (CEFITEC), Department of Physics, Faculty of Science and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0244-8127","authenticated-orcid":false,"given":"D\u00e1rio","family":"Garcia","sequence":"additional","affiliation":[{"name":"Center of Physics and Technological Research (CEFITEC), Department of Physics, Faculty of Science and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0591-5309","authenticated-orcid":false,"given":"Hugo","family":"Costa","sequence":"additional","affiliation":[{"name":"Center of Physics and Technological Research (CEFITEC), Department of Physics, Faculty of Science and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1951-2957","authenticated-orcid":false,"given":"Bruno D.","family":"Tib\u00farcio","sequence":"additional","affiliation":[{"name":"Center of Physics and Technological Research (CEFITEC), Department of Physics, Faculty of Science and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal"}]},{"given":"Joana","family":"Almeida","sequence":"additional","affiliation":[{"name":"Center of Physics and Technological Research (CEFITEC), Department of Physics, Faculty of Science and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,4]]},"reference":[{"key":"ref_1","unstructured":"(2022, August 04). 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