Thermal lensing in cryogenic sapphire substrates

Tomaru, T.; Suzuki, Toshikazu; Miyoki, S.; Uchiyama, Takashi; Taylor, C.; Yamamoto, A.; Shintomi, T.; Kuroda, K.

doi:10.1088/0264-9381/19/7/412

Cited by 38 publications

(29 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The assumed values for lower temperatures represent a conservative extrapolation. Tomaru et al [26] measured β for sapphire at temperatures down to 5 K. But in the temperature range from 5 K to 40 K they were TABLE I. Assumed thermal properties for silicon and sapphire.…”

Section: A Materials Propertiesmentioning

confidence: 99%

Thermorefractive noise of finite-sized cylindrical test masses

et al. 2011

View full text Add to dashboard Cite

We present an analytical solution for the effect of thermorefractive noise considering finite-sized cylindrical test masses. For crystalline materials at low temperatures the effect of finite dimensions becomes important. The calculations are independently performed using the FluctuationDissipation-Theorem and Langevin's approach. Our results are applied to the input test mass of the current and future cryogenic gravitational wave detectors CLIO, LCGT, and ET and are compared to the respective standard quantum limit. For a substrate temperature of 10 K we find that the thermorefractive noise amplitude of the silicon input test mass in ET is only a factor of 2 below the standard quantum limit for frequencies above 500 Hz. Thus, thermorefractive noise of the input test mass could become a severe limitation if one uses techniques to beat the standard quantum limit like, e.g., squeezing. In contrast the effect of thermorefractive noise of the input test mass is negligible for CLIO and LCGT.

show abstract

Section: A Materials Propertiesmentioning

confidence: 99%

Thermorefractive noise of finite-sized cylindrical test masses

et al. 2011

View full text Add to dashboard Cite

show abstract

“…Sapphire is transparent to the standard wavelength adopted in the gravitational wave detectors (1064 nm). It shows relatively small thermal lensing [51] due to its large thermal conductivity at low temperature (2330 W· m −1 K −1 at 10 K), but the high optical absorption (about 90 ppm/cm [52]) measured in the available substrate samples, constrains the interferometer design and limits the future light power increase in the main Fabry-Perot cavities. Future improvement in the optical properties of the Sapphire substrate could enhance the possibilities of this solution.…”

Section: Mirror Thermal Noisementioning

confidence: 99%

Toward a third generation of gravitational wave observatories

Punturo

Lück

2010

Gen Relativ Gravit

View full text Add to dashboard Cite

Large gravitational wave interferometric detectors, like Virgo and LIGO, demonstrated the capability to reach their design sensitivity, but to transform these machines into an effective observational instrument for gravitational wave astronomy a large improvement in sensitivity is required. Advanced detectors in the near future and third generation observatories in slightly more than one decade will open the possibility to perform gravitational wave astronomical observations from the Earth. An overview of the technological progress needed to realize a third generation observatory, like the Einstein Telescope (ET), and a possible evolution scenario are discussed in this paper.

show abstract

“…As the thermo-refractive coefficient of sapphire is smaller than 9 Â 10 À8 K À1 at temperatures below 40 K (Ref. 13) the effect of the windows onto the final results is negligible.…”

mentioning

confidence: 99%