{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T06:38:47Z","timestamp":1784011127540,"version":"3.55.0"},"reference-count":23,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2013,1,4]],"date-time":"2013-01-04T00:00:00Z","timestamp":1357257600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The efficient generation of second-harmonic light and squeezed light requires non-linear crystals that have low absorption at the fundamental and harmonic wavelengths. In this work the photo-thermal self-phase modulation technique is exploited to measure the absorption coefficient of periodically poled potassium titanyl phosphate (PPKTP) at 1,550 nm and 775 nm. Themeasurement results are (84\u00b140) ppm\/cmand (127\u00b124) ppm\/cm, respectively. We conclude that the performance of state-of-the-art frequency doubling and squeezed light generation in PPKTP is not limited by absorption.<\/jats:p>","DOI":"10.3390\/s130100565","type":"journal-article","created":{"date-parts":[[2013,1,4]],"date-time":"2013-01-04T10:53:47Z","timestamp":1357296827000},"page":"565-573","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Absorption Measurements of Periodically Poled Potassium Titanyl Phosphate (PPKTP) at 775 nm and 1550 nm"],"prefix":"10.3390","volume":"13","author":[{"given":"Jessica","family":"Steinlechner","sequence":"first","affiliation":[{"name":"Institut f\u00fcr Gravitationsphysik, Leibniz Universit\u00e4t Hannover and Max-Planck-Institut f\u00fcr Gravitationsphysik (Albert-Einstein-Institut), Callinstr. 38, 30167 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefan","family":"Ast","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Gravitationsphysik, Leibniz Universit\u00e4t Hannover and Max-Planck-Institut f\u00fcr Gravitationsphysik (Albert-Einstein-Institut), Callinstr. 38, 30167 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christoph","family":"Kr\u00fcger","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Gravitationsphysik, Leibniz Universit\u00e4t Hannover and Max-Planck-Institut f\u00fcr Gravitationsphysik (Albert-Einstein-Institut), Callinstr. 38, 30167 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amrit","family":"Singh","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Gravitationsphysik, Leibniz Universit\u00e4t Hannover and Max-Planck-Institut f\u00fcr Gravitationsphysik (Albert-Einstein-Institut), Callinstr. 38, 30167 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tobias","family":"Eberle","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Gravitationsphysik, Leibniz Universit\u00e4t Hannover and Max-Planck-Institut f\u00fcr Gravitationsphysik (Albert-Einstein-Institut), Callinstr. 38, 30167 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vitus","family":"H\u00e4ndchen","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Gravitationsphysik, Leibniz Universit\u00e4t Hannover and Max-Planck-Institut f\u00fcr Gravitationsphysik (Albert-Einstein-Institut), Callinstr. 38, 30167 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roman","family":"Schnabel","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Gravitationsphysik, Leibniz Universit\u00e4t Hannover and Max-Planck-Institut f\u00fcr Gravitationsphysik (Albert-Einstein-Institut), Callinstr. 38, 30167 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2013,1,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3663","DOI":"10.1103\/PhysRevLett.68.3663","article-title":"Realization of the einstein-podolsky-rosen paradoxon for continuous variables","volume":"68","author":"Ou","year":"1992","journal-title":"Phys. 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