Quantum Enhancement of a 4 km Laser Interferometer Gravitational-Wave Detector by Sheon S. Y. Chua

Author:Sheon S. Y. Chua
Language: eng
Format: epub, pdf
Publisher: Springer International Publishing, Cham

(6.4)

(6.5)

The variance of the photon number relative to quantum noise limit can be calculated as

(6.6)

with the variance of the vacuum field being unity. This illustrates that presence of optical loss returns the noise variance of the optical field back towards the quantum noise limit.

It follows that the impact of optical losses can greatly hinder the amount of squeezing measurable. Figure 6.8 illustrates the effect of optical loss on squeezing magnitude measurement for different loss percentages. It also illustrates the larger attenuation impact with greater input squeezing. For example, with 50 % optical loss, 5 dB generated squeezing becomes 1.8 dB measured squeezing, a reduction of 3.2 dB squeezing. This is compared with 40 dB generated squeezing becoming 3 dB measured squeezing, an attenuation of 37 dB.

Fig. 6.8Optical loss impact on measured squeezing magnitude, as a function of input squeezing magnitude. Optical loss curves of 5, 15, 30 and 50 % are shown. Reprinted with permission from [19], copyright (2014) by IOP Publishing

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.