{"id":527,"date":"2020-05-22T03:36:21","date_gmt":"2020-05-22T03:36:21","guid":{"rendered":"http:\/\/www.shalomeo.com\/blog\/?p=527"},"modified":"2020-05-22T03:36:21","modified_gmt":"2020-05-22T03:36:21","slug":"ndyvo4s-advantages-over-ndyag","status":"publish","type":"post","link":"https:\/\/www.shalomeo.com\/blog\/ndyvo4s-advantages-over-ndyag\/527.html","title":{"rendered":"Nd:YVO4\u2019s advantages over Nd:YAG"},"content":{"rendered":"<p>As high as about five times larger absorption efficient over a wide pumping bandwidth around 808 nm (therefore, the dependency on pumping wavelength is much lower and a strong tendency to the single mode output).<\/p>\n<p>As large as three times larger stimulated emission cross-section at the lasing wavelength of 1064nm.<\/p>\n<p>Lower lasing threshold and higher slope efficiency.<\/p>\n<p>As a uniaxial crystal with a large birefringence, the emission is only linearly polarized.<\/p>\n<p><strong><b>Laser Properties of Nd:YVO4<\/b><\/strong><\/p>\n<ol>\n<li>One of the most attractive character of Nd:YVO4 is, compared with Nd:YAG, it has 5 times larger absorption coefficient in a broader absorption bandwidth around the 808 nm peak pump wavelength, which just matches the standard of high power laser diodes currently available. This means a smaller <strong><b><a href=\"http:\/\/www.shalomeo.com\/product\/laser-components\/laser-crystals\/ndyvo4-crystals-10.html\">Nd:YVO4 crystal<\/a>\u00a0<\/b><\/strong>that could be used for the laser, leading to a more compact laser system. For a given output power, this also means a lower power level at which the laser diode operates, thus extending the lifetime of the expensive laser diode. The broader absorption bandwidth of Nd:YVO4 which may reaches 2.4 to 6.3 times that of Nd:YAG, is also valuable. Besides more efficient pumping, Nd:YVO4 also means a broader range of selection of diode specifications. This will be helpful to laser system makers for wider tolerance and lower cost choice.<\/li>\n<li>Nd:YVO4 crystal has larger stimulated emission cross-sections, both at 1064nm and 1342nm. When a-axis cut Nd:YVO4 crystal lasing at 1064m, it is about 4 times higher than that of Nd:YAG, while at 1340nm the stimulated cross-section is 18 times larger, which leads to a CW operation completely outperforming Nd:YAG at 1320nm. These make Nd:YVO4 laser be easy to maintain a strong single line emission at the two wavelengths.<\/li>\n<li>Another important character of Nd:YVO4 lasers is, because it is an uniaxial rather than a high symmetry of cubic as Nd:YAG, what it emits is only a linearly polarized, thus avoiding undesired birefringent effects on the frequency conversion. Although the lifetime of Nd:YVO4 is about 2.7 times shorter than that of Nd:YAG, its slope efficiency can be still quite high for a proper design of laser cavity, because of its high pump quantum efficiency.<\/li>\n<\/ol>\n<p>The major laser properties of <strong>Nd:YVO4<\/strong> vs <strong>Nd:YAG<\/strong> are listed in Table below, including stimulated emission cross-sections (\u03c3), Absorption Coefficient (\u03b1) Fluorescent lifetime (\u03c4),Absorption Length (La),threshold Power (Pth) and Pump Quantum Efficiency (\u03b7s).<\/p>\n<p><img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-medium wp-image-528\" src=\"http:\/\/www.shalomeo.com\/blog\/wp-content\/uploads\/2020\/05\/Nd-YVO4-Crystals522-300x214.jpg\" alt=\"\" width=\"300\" height=\"214\" srcset=\"https:\/\/www.shalomeo.com\/blog\/wp-content\/uploads\/2020\/05\/Nd-YVO4-Crystals522-300x214.jpg 300w, https:\/\/www.shalomeo.com\/blog\/wp-content\/uploads\/2020\/05\/Nd-YVO4-Crystals522.jpg 350w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>As high as about five times larger absorption effi &hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[188,189,190,187],"_links":{"self":[{"href":"https:\/\/www.shalomeo.com\/blog\/wp-json\/wp\/v2\/posts\/527"}],"collection":[{"href":"https:\/\/www.shalomeo.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.shalomeo.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.shalomeo.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.shalomeo.com\/blog\/wp-json\/wp\/v2\/comments?post=527"}],"version-history":[{"count":0,"href":"https:\/\/www.shalomeo.com\/blog\/wp-json\/wp\/v2\/posts\/527\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.shalomeo.com\/blog\/wp-json\/wp\/v2\/media?parent=527"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.shalomeo.com\/blog\/wp-json\/wp\/v2\/categories?post=527"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.shalomeo.com\/blog\/wp-json\/wp\/v2\/tags?post=527"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}