Enhancement of SHG for Squeezing in aLIGO: 2013 SURF

Document #:

LIGO-P1400193-v1

Document type:

P - Publications

Abstract:

Second harmonic generation is employed to increase LIGO's sen-
sitivity in the shot noise dominated bandwidth (100 Hz and above)
by introducing squeezed states through the dark port of the interfer-
ometer. This project characterizes and improves the second harmonic
generation of periodically poled KTP in a resonant cavity locked by a
PDH servo. These enhancements include custom mechanical stages to
control movement of the mirrors in the horizontal direction and retain
information about optimal mirror positions if the mirror mounts need
to be moved. Additionally, a digital temperature controller featuring
Beckho Ethercat terminals and TwinCat PLC software. The servo's
response characteristics (set-temperature response and step function
response) have been analyzed and suggest stable performance on the
order of days.

Files in Document:

• LIGO SURF FINAL REPORT FOR Nathan Zhao (Final TexMaker.pdf, 12.2 MB)

Other Files:

• Editable Version (Final TexMaker.tex, 48.1 kB)

Topics:

• Squeezer
• Fabrication

Authors:

• Nathan Zhao

Keywords:

Squeezing SHG Second Harmonic Generation aLIGO SURF2014

Referenced by:

• LIGO-P1400235: LIGO SURF 2014 Final Reports
• LIGO-E1700004: aLIGO, SQZ, SHG