Abstract

Nulling interferometry was first introduced in the 1970’s and proved to be successful in detecting and imaging exoplanets. Through the use of a photonic device called a 3D tricoupler we can perform both nulling interferometry and fringe tracking simultaneously. A 3D tricoupler device comprises of 3 single mode waveguides which can provide achromatic interferometric suppression of star light. We present laboratory characterisation of the 3D tricouplers fabricated by the femtosecond direct write technique as well as numerical solutions to coupled mode equations providing a parameter scan to optimise fabrication. We also present polarisation dependency of the tricoupler devices as well as an interferometric analysis of the output intensity as a function of input phase.

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