{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,18]],"date-time":"2025-12-18T14:21:12Z","timestamp":1766067672424,"version":"build-2065373602"},"reference-count":48,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2022,12,2]],"date-time":"2022-12-02T00:00:00Z","timestamp":1669939200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia\u2013Minist\u00e9rio da Ci\u00eancia, Tecnologia e Ensino Superior (FCT-MCTES)","doi-asserted-by":"publisher","award":["UIDB\/00068\/2020","EXPL\/FIS-OTI\/0332\/2021"],"award-info":[{"award-number":["UIDB\/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":["Energies"],"abstract":"<jats:p>A seven-rod solar laser head was conceptualized and numerically studied to improve the tracking error compensation capacity and power stability in end-side-pumping schemes. It was composed of a first-stage heliostat\u2013parabolic mirror system, a second-stage fused silica aspheric lens and a third-stage conical pumping cavity, within which seven Nd:YAG rods were mounted. Highly stable solar laser emission, with a power loss inferior to 5% for tracking errors up to \u00b10.4\u00b0, could potentially be enabled with seven 4 mm diameter, 13 mm length rods. The tracking error width at 10% laser power loss was about 1.0\u00b0, which is 1.65 times higher than the experimental record, attained by a dual-rod side-pumping prototype. Furthermore, a total multimode laser power of about 41.2 W could also be achieved, corresponding to 23.3 W\/m2 collection and 2.5% solar-to-laser power conversion efficiencies, which are 1.65 and 1.36 times higher than those obtained with the dual-rod side-pumping prototype. They are also 1.27 and 1.12 times higher than the multirod experimental records in multimode regime for the same rod material.<\/jats:p>","DOI":"10.3390\/en15239140","type":"journal-article","created":{"date-parts":[[2022,12,2]],"date-time":"2022-12-02T03:28:04Z","timestamp":1669951684000},"page":"9140","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Seven-Rod Pumping Concept for Highly Stable Solar Laser Emission"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0591-5309","authenticated-orcid":false,"given":"Hugo","family":"Costa","sequence":"first","affiliation":[{"name":"Centre of Physics and Technological Research, Physics Department, NOVA School of Science and Technology, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4406-4108","authenticated-orcid":false,"given":"Dawei","family":"Liang","sequence":"additional","affiliation":[{"name":"Centre of Physics and Technological Research, Physics Department, NOVA School of Science and Technology, 2829-516 Caparica, Portugal"}]},{"given":"Joana","family":"Almeida","sequence":"additional","affiliation":[{"name":"Centre of Physics and Technological Research, Physics Department, NOVA School of Science and Technology, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2888-718X","authenticated-orcid":false,"given":"Miguel","family":"Catela","sequence":"additional","affiliation":[{"name":"Centre of Physics and Technological Research, Physics Department, NOVA School of Science and Technology, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0244-8127","authenticated-orcid":false,"given":"D\u00e1rio","family":"Garcia","sequence":"additional","affiliation":[{"name":"Centre of Physics and Technological Research, Physics Department, NOVA School of Science and Technology, 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":"Centre of Physics and Technological Research, Physics Department, NOVA School of Science and Technology, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9370-1997","authenticated-orcid":false,"given":"Cl\u00e1udia R.","family":"Vistas","sequence":"additional","affiliation":[{"name":"Centre of Physics and Technological Research, Physics Department, NOVA School of Science and Technology, 2829-516 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"083104","DOI":"10.1063\/1.2998981","article-title":"100 W-class solar pumped laser for sustainable magnesium-hydrogen energy cycle","volume":"104","author":"Yabe","year":"2008","journal-title":"J. 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