Heterodyne Interferometer with Phasemeter for LISA

The LISA Technology Package (LTP) is a technology demonstration mission in preparation for the LISA space-borne gravitational wave detector. A central part of the LTP is the optical metrology package (heterodyne interferometer with phasemeter) which monitors the distance between two test masses with a noise level of 10 pm/√Hz. Detailed laboratory investigations have demonstrated the feasibility of the interferometer concept, the alignment measurement techniques, and the phasemeter operation. An engineering model of the optical bench is complete and undergoes extensive tests.

Bibliography

[1] G. Heinzel et al., The LTP interferometer and phasemeter, Class. Quantum Grav. 21 (2004) S581 – S587