Suppressing ghost beams: Backlink options for LISA

In this article we discuss possible design options for the optical phase reference system, the so called backlink, between two moving optical benches in a LISA satellite. The candidates are based on two approaches: Fiber backlinks, with additional features like mode cleaning cavities and Faraday isolators, and free beam backlinks with angle compensation techniques. We will indicate dedicated ghost beam mitigation strategies for the design options and we will point out critical aspects in case of an implementation in LISA. © Published under licence by IOP Publishing Ltd. DFG/SFB/1128 Deutsches Zentrum für Luft- und Raumfahrt (DLR) Bundesministerium für Wirtschaft und Technologie/50 OQ 0601 NASA/NNX15AC48G