An Alexandrite Laser System for Positronium Laser Cooling

• DOI: 10.2139/ssrn.4821804
• Publication Date: 2024-05-08T20:56:43Z
• Authors: Natali Gusakova; Antoine Camper; Ruggero Caravita; Luca Penasa; Lisa Theresa Glö...; Tim Wolz; Valts Krumins; Fredrik Parnefjo...; Saiva Huck; Marco Volponi; Benjamin Rienaecker; Gunn Khatri; Jan Malamant; Sebastiano Mariazzi; Roberto Sennen Brusa; Louis Cabaret; Daniel Pierre Co...; Michael Doser
• Keywords: Positronium

We report on a Q-switched alexandrite based ∼100 ns long pulse duration ultra-violet laser system. The central wavelength of the fundamental pulse is set by a Volume Bragg Grating in reflection and can be tuned between 728 nm and 742 nm. The spectral bandwidth is ∼130 GHz. This laser system was designed in view of Doppler cooling of a cloud of a near room temperature positronium by strongly saturating the 13S–23P transition. In addition, we report on the development of a KD*P Pockels cell driver designed to both Q-switch the cavity and induce a sharp falling edge of the laser pulse so that the end of the positronium-laser interaction time can be controlled with nanosecond precision.<br/>We report on a Q-switched alexandrite based- 100 ns long pulse duration ultra-violet laser system. The central wavelength of the fundamental pulse is set by a Volume Bragg Grating in reflection and can be tuned between 728 nm and 742 nm. The spectral bandwidth is- 130 GHz. This laser system was designed in view of Doppler cooling of a cloud of a near room temperature positronium by strongly saturating the 1 3 S- 2 3 P transition. In addition, we report on the development of a KD*P Pockels cell driver designed to both Q-switch the cavity and induce a sharp falling edge of the laser pulse so that the end of the positronium-laser interaction time can be controlled with nanosecond precision.<br/>