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arXiv · 2109.13872

Laser Cooling of a Yb Doped Silica Fiber by 18 Kelvin From Room Temperature

Brian Topper·Mostafa Peysokhan·Alexander R. Albrecht·Angel S. Flores·Stefan Kuhn·Denny Haessner·Sigrun Hein·Christian Hupel·Johannes Nold·Nicoletta Haarlammert·Thomas Schreiber·Mansoor Sheik-Bahae·Arash Mafi
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Abstract

A ytterbium doped silica optical fiber has been cooled by 18.4K below ambient temperature by pumping with 20W of 1035nm light in vacuum. In air, cooling by 3.6K below ambient was observed with the same 20W pump. The temperatures were measured with a thermal imaging camera and differential luminescence thermometry. The cooling efficiency is calculated to be 1.2+-0.1%. The core of the fiber was codoped with Al3+ for an Al to Yb ratio of 6:1, to allow for a larger Yb concentration and enhanced laser cooling.

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Brian Topper, Mostafa Peysokhan, Alexander R. Albrecht, Angel S. Flores, Stefan Kuhn, Denny Haessner, Sigrun Hein, Christian Hupel, Johannes Nold, Nicoletta Haarlammert, Thomas Schreiber, Mansoor Sheik-Bahae, Arash Mafi. 2021-09-28. Laser Cooling of a Yb Doped Silica Fiber by 18 Kelvin From Room Temperature. https://doi.org/10.1364/ol.444709

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