Automated, deep reactive ion etching free fiber coupling to nanophotonic devices

TL;DR

This paper introduces a rapid, scalable, and DRIE-free method for aligning nanophotonic devices with optical fibers, achieving precision comparable to traditional DRIE-based techniques, suitable for quantum photonic applications.

Contribution

The authors present a novel, temperature-stable self-aligning fiber coupling method that is easy to implement, versatile, and fully automatable, eliminating the need for DRIE processes.

Findings

Alignment precision of 1.2±0.4 μm achieved

Thermal cycling stability within 0.2 μm

Method is scalable and suitable for quantum photonics

Abstract

Rapid development in integrated optoelectronic devices and quantum photonic architectures creates a need for optical fiber to chip coupling with low losses. Here we present a fast and generic approach that allows temperature stable self-aligning connections of nanophotonic devices to optical fibers. We show that the attainable precision of our approach is equal to that of DRIE-process based couplings. Specifically, the initial alignment precision is $1.2\pm 0.4\mu m$, the average shift caused by mating $<0.5\mu m$, which is in the order of the precision of the concentricity of the employed fiber, and the thermal cycling stability is $<0.2\mu m$. From these values the expected overall alignment offset is calculated as $1.4 \pm 0.4\mu m$. These results show that our process offers an easy to implement, versatile, robust and DRIE-free method for coupling photonic devices to optical fibers. It can be fully automated and is therefore scalable for coupling to novel devices for quantum photonic systems.