Crossed optical cavities with large mode diameters

Heinz, Andre; Trautmann, Jan; Santic, Neven; Park, Annie Jihyun; Bloch, Immanuel und Blatt, Sebastian (2021): Crossed optical cavities with large mode diameters. In: Optics Letters, Vol. 46, No. 2: pp. 250-253

Abstract

We report on a compact, ultrahigh-vacuum compatible optical assembly to create large-scale, two-dimensional optical lattices for use in experiments with ultracold atoms. The assembly consists of an octagon-shaped spacer made from ultra-low-expansion glass, to which we optically contact four fused silica cavity mirrors, making it highly mechanically and thermally stable. The mirror surfaces are nearly plane-parallel, which allows us to create two perpendicular cavity modes with diameters similar to 1mm. Such large mode diameters are desirable to increase the optical lattice homogeneity, but lead to strong angular sensitivities of the coplanarity between the two cavity modes. We demonstrate a procedure to precisely position each mirror substrate that achieves a deviation from coplanarity of d = 1(5) mu M. Creating large optical lattices at arbitrary visible and near-infrared wavelengths requires significant power enhancements to overcome limitations in the available laser power. The cavity mirrors have a customized low-loss mirror coating that enhances the power at a set of relevant visible and near-infrared wavelengths by up to 3 orders of magnitude.. (C) 2021 Optical Society of America

• Item Type: Journal article
• Faculties: Physics
• Subjects: 500 Science > 530 Physics
• ISSN: 0146-9592
• Language: English