Positional Accuracy of 3D Printed Quantum Emitter Fiber Couplers

Abstract

Precise positioning of optical elements plays a key role in the performance of optical systems. While additive manufacturing techniques such as 3D printing enable the creation of entire complex micro-objectives in one step, thus rendering lens alignment unnecessary, certain applications require precise positional alignment of the printing process with respect to the substrate. For example, in order to efficiently couple quantum emitters to single-mode fibers, which is a crucial step in the development of real world quantum networks, precise alignment between the emitter, the coupling optics, and the single-mode fiber is of utmost importance. In this work, the positioning accuracy of a Photonics Professional GT (Nanoscribe GmbH) 3D printing machine is evaluated by using the integrated piezo stage to align to gold markers that is manufactured via e-beam lithography. By running a statistical analysis of 38 printing cycles, a mean positional error of only 80 nm is determined. Additionally, an entire system is 3D printed that can couple quantum emitters to optical single-mode fibers. Examining the focal spot of the 3D printed micro-optics, a positional accuracy of ≈ 1 µm in all three dimensions is found, as well as excellent quality of the focal spot.