On the mechanical quality factors of cryogenic test masses from fused silica and crystalline quartz
On the mechanical quality factors of cryogenic test masses from fused silica and crystalline quartz
复制标题
熔融石英和结晶石英低温测试质量的机械品质因数
DOI：
--
复制
发表时间：
2007
期刊：
影响因子：
--
通讯作者：
P. Seidel
中科院分区：
文献类型：
--
作者：
A. Schroeter;R. Nawrodt;R. Schnabel;S. Reid;I. Martin;S. Rowan;C. Schwarz;T. Koettig;R. Neubert;M. Thurk;W. Vodel;A. Tunnermann;K. Danzmann;P. Seidel
目前的干涉引力波探测器（IGWD）在室温下运行，测试质量由熔融石英制成。熔融石英对 1064 nm 激光波长的吸收率非常低。它也非常适合在探测器信号频带内实现低热噪声本底，因为它提供了低机械损耗，即。 e.室温下的高品质因数（Q 因数）。然而，为了进一步降低热噪声，将测试质量冷却到低温可能是一种有趣的技术。在这里，我们比较了熔融石英及其晶体对应物的测试质量的声学本征模在低温下的 Q 因子测量结果。我们的结果表明，熔融石英的机械损耗随着温度的降低而增加，并且在频率略高于 10 kHz 时在 30 K 时达到最大值。结晶石英的损耗通常表现出较低的值，甚至低于熔融石英在 10 K 以下的室温值。我们的结果表明，与熔融石英相比，结晶石英在冷却时具有相当窄和较低的耗散峰值，因此更有希望作为在低温下运行的 IGDW 的测试质量材料。讨论了两种材料不同 Q 因子与温度行为的根源。
Current interferometric gravitational wave detectors (IGWDs) are operated at room temperature with test masses made from fused silica. Fused silica shows very low absorption at the laser wavelength of 1064 nm. It is also well suited to realize low thermal noise floors in the detector signal band since it offers low mechanical loss, i. e. high quality factors (Q factors) at room temperature. However, for a further reduction of thermal noise, cooling the test masses to cryogenic temperatures may prove an interesting technique. Here we compare the results of Q factor measurements at cryogenic temperatures of acoustic eigenmodes of test masses from fused silica and its crystalline counterpart. Our results show that the mechanical loss of fused silica increases with lower temperature and reaches a maximum at 30 K for frequencies of slightly above 10 kHz. The losses of crystalline quartz generally show lower values and even fall below the room temperature values of fused silica below 10 K. Our results show that in comparison to fused silica, crystalline quartz has a considerably narrower and lower dissipation peak on cooling and thus has more promise as a test mass material for IGDWs operated at cryogenic temperatures. The origin of the different Q factor versus temperature behavior of the two materials is discussed.