µJ-level multi-cycle terahertz generation in a periodically poled Rb:KTP crystal

• DOI: 10.1364/ol.413410
• Publication Date: 2021-01-13T19:04:53Z
• Authors: Wenlong Tian; Giovanni Cirmi; Halil T. Olgun; Patrick Mutter; Carlota Canalias; Andrius Zukauskas; Lu Wang; Elias Kueny; Frederike Ahr; Anne-Laure Calendron; Fabian Reichert; Kore Hasse; Yi Hua; Damian N. Schimpf; Hüseyin Çankaya; Mikhail Pergament; Michael Hemmer; Nicholas Matlis; Valdas Pasiskevicius; Fredrik Laurell; Franz X. Kärtner
• Keywords: Crystal (programming language); Optical materials; Potassium titanyl phosphate

We demonstrate multi-cycle terahertz (MC-THz) generation in a 15.5 mm long periodically poled rubidium (Rb)-doped potassium titanyl phosphate (Rb:PPKTP) crystal with poling period of 300 µm. By cryogenically cooling the to 77 K, up 0.72 µJ energy is obtained at frequency 0.5 THz 3 GHz bandwidth. A maximum internal optical-to-terahertz conversion efficiency 0.16% achieved, which comparable results achieved using lithium niobate crystal. Neither photorefractive effects nor damage was observed <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mn>900</mml:mn> </mml:mrow> <mml:mspace width="thickmathspace"/> <mml:msup> <mml:mi mathvariant="normal">m</mml:mi> mathvariant="normal">J</mml:mi> <mml:mo>/</mml:mo> mathvariant="normal">c</mml:mi> <mml:mn>2</mml:mn> </mml:msup> </mml:math> , showing great potential Rb:PPKTP for multi-millijoule-level MC-THz generation.