Arm cavity round-trip loss measurement with ITM inhomogeneity and birefringence

Document #:

JGW-T2011633-v4

Document type:

T

Submitted by:

Yuta Michimura

Updated by:

Yuta Michimura

Document Created:

25 Apr 2020, 15:40

Contents Revised:

25 Apr 2020, 16:35

Metadata Revised:

25 Jun 2021, 11:11

Abstract:

Arm cavity round-trip loss (RTL) is usually estimated from the power reduction in the arm reflection when the arm cavity is locked. But this method can be wrong when there is significant ITM birefringence and when you are detecting s-pol and p-pol with some bias.
Correct way of measuring RTL is discussed.

Related klog:
https://klog.icrr.u-tokyo.ac.jp/osl/?r=7307
https://klog.icrr.u-tokyo.ac.jp/osl/?r=9314
https://klog.icrr.u-tokyo.ac.jp/osl/?r=9393

Files in Document:

• RoundtripLossBirefringence.pdf (683.1 kB)
• RoundtripLossBirefringence.ppt (574.5 kB)

Topics:

• Activity:KAGRA
• Detector:Interferometer

Authors:

• Yutaro Enomoto
• Yuta Michimura

Keywords:

birefringence

Related Documents:

• JGW-G1910369: Polarization issue in PRC
• JGW-G1910388: Polarization issue in the central IFO
• JGW-T1910380: How to compute birefringence map from TWE maps

Referenced by:

• JGW-T2113073: TMS polarization monitor plan
• JGW-D2112956: [CONFIDENTIAL] Specification sheet for non-polarizing beam splitters for in-air optical tables

Approved for use in external presentations:

Unapproved