In summer 2009 the transition from GEO600 to GEO HF has started. This upgrade includes among other important changes an increase of the light power within the interferometer from 3kW to 20kW. And that is what I am working on.
Increasing the light power as well as the implementation of squeezing will both reduce shot noise and thereby lead to a better sensitivity at high frequencies. Only with both techniques GEO HF will be able to achieve good sensitivities at high frequencies and above 2 kHz GEO will even beat the sensitivities of the enhanced detectors!
What is the problem?
Increasing the light power is not done by buying or building a new laser even although it is a part of it. Additionally there will be changes at the input mode cleaners and several problems resulting from the simple fact that there will be more light. One example is stray light coupling into different control channels but there is various more stuff to investigate.
Max Planck Institute for Gravitational Physics
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