Marginally stable cavity simulation : FFT vs Modal Model

Document #:

LIGO-T1000226-v2

Document type:

T - Technical notes

Abstract:

The sideband field resonating in a marginally stable cavity with thermal deformation was calculated using FFT and modal model, and a large discrepancy was observed. This document explains the limitation of the use of modal model when the mode mismatch is not good.

Files in Document:

• compare FFT and modal model calculations of fields in marginally stable cavity (T1000226-v2.pdf, 1.7 MB)
• matlab code to calculate the field in a FP cavity using Hankel transform (HnklFP.m, 3.2 kB)

Topics:

• Core Optics
• Modelling

Authors:

• Hiro Yamamoto

Keywords:

modal model FFT marginal stable cavity SB

Notes and Changes:

Result using Hankel Transform is added