Laser Interferometer Space Antenna: Challenges and new prospects

The Laser Interferometer Space Antenna (LISA) will be the first space-based gravitational wave (GW) detector designed to be sensitive to sources radiating 0.1 mHz to 1 Hz frequency band. LISA's interferometer layout entails approximate 2.5 gigameter interferometer arms oriented in a  triangular configuration which enforces a picometer level optical pathlength stability requirement to detect GWs with strains of order 10-21. In addition to detecting new astrophysical sources, LISA's interferometer design and sensitivity to low frequencies also provide exciting opportunities to detect subtle non-linear effects of General Relativity like the gravitational memory effect. In this talk, I will give a broad overview of the challenges involved in achieving the desired sensitivity. I will focus on my work on Arm locking, a feedback control system designed to suppress the dominant laser frequency noise by taking advantage of the stability of the LISA arm. Furthermore, I will also present my recent work on a time domain data stacking method designed to extract the gravitational memory imprints of LIGO binaries in the LISA data streams