Dielectric mirror leakage at large angles of incidence limits the effectiveness of solid state optical refrigerators due to
reheating caused by photon absorption in an attached load. In this paper, we present several thermally conductive link
solutions to greatly reduce the net photon absorption. The Los Alamos Solid State Optical Refrigerator (LASSOR) has
demonstrated cooling of a Yb<sup>3+</sup> doped ZBLANP glass to 208 K. We have designed optically isolating thermal link
geometries capable of extending cooling to a typical heat load with minimal absorptive reheating, and we have tested the
optical performance of these designs. A surrogate source operating at 625 nm was used to mimic the angular distribution
of light from the LASSOR cooling element. While total link performance is dependent on additional factors, we have
found that the best thermal link reduced the net transmission of photons to 0.04%, which includes the trapping mirrors
8.1% transmission. Our measurements of the optical performance of the various link geometries are supported by
computer simulations of the designs using Code V, a commercially available optical modeling software package.
We have used the thermal modeling tool in COMSOL Multiphysics to investigate factors that affect the thermal
performance of the optical refrigerator. Assuming an ideal cooling element and a non-absorptive dielectric trapping
mirror, the three dominant heating factors are blackbody radiation from the surrounding environment, conductive heat
transfer through mechanical supports, and the absorption of fluoresced photons transmitted through the thermal link.
Laboratory experimentation coupled with computer modeling using Code V optical software have resulted in link
designs capable of reducing the transmission to 0.04% of the fluoresced photons emitted toward the thermal link. The
ideal thermal link will have minimal surface area, provide complete optical isolation for the load, and possess high
thermal conductivity. Modeling results imply that a 1cm<sup>3</sup> load can be chilled to 102 K with currently available cooling
efficiencies using a 100 W pump laser on a YB:ZBLANP system, and using an ideal link that has minimal surface area
and no optical transmission. We review the simulated steady-state cooling temperatures reached by the heat load for
several link designs and system configurations as a comparative measure of how well particular configurations perform.