Low Mechanical Loss TiO2:GeO2 Coatings for Reduced Thermal Noise in Gravitational Wave Interferometers
Low Mechanical Loss TiO2:GeO2 Coatings for Reduced Thermal Noise in Gravitational Wave Interferometers
复制标题
低机械损耗 TiO2:GeO2 涂层可降低引力波干涉仪中的热噪声
DOI：
10.1103/physrevlett.127.071101
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发表时间：
2021
影响因子：
8.6
通讯作者：
Bassiri, Riccardo
中科院分区：
文献类型：
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作者：
Vajente, Gabriele;Yang, Le;Davenport, Aaron;Fazio, Mariana;Ananyeva, Alena;Zhang, Liyuan;Billingsley, Garilynn;Prasai, Kiran;Markosyan, Ashot;Bassiri, Riccardo
目前和计划中的引力波干涉探测器的灵敏度在100 Hz左右的最关键频率区域受到量子噪声和热噪声的限制。后者主要由布朗噪声：热运动起源于干涉仪反射镜中使用的电介质涂层中的弹性能量耗散。能量耗散是以机械损耗角为特征的材料特性。我们已经确定了二氧化钛（）和二氧化锗（）的混合物，其显示出足够低的内部耗散水平，以相对于现有技术的材料提供布朗噪声水平的几乎2倍的改善。我们表明，通过在干涉仪反射镜的高折射率层中使用44%和56%的混合物，可以实现符合设计要求的热噪声水平。这些结果是生产满足高级LIGO（激光干涉引力波天文台）和Virgo探测器计划升级的热噪声要求所需的反射镜的关键一步。
The sensitivity of current and planned gravitational wave interferometric detectors is limited, in the most critical frequency region around 100 Hz, by a combination of quantum noise and thermal noise. The latter is dominated by Brownian noise: thermal motion originating from the elastic energy dissipation in the dielectric coatings used in the interferometer mirrors. The energy dissipation is a material property characterized by the mechanical loss angle. We have identified mixtures of titanium dioxide () and germanium dioxide () that show internal dissipations at a level of, low enough to provide improvement of almost a factor of 2 on the level of Brownian noise with respect to the state-of-the-art materials. We show that by using a mixture of 44%and 56%in the high refractive index layers of the interferometer mirrors, it would be possible to achieve a thermal noise level in line with the design requirements. These results are a crucial step forward to produce the mirrors needed to meet the thermal noise requirements for the planned upgrades of the Advanced LIGO (Laser Interferometer Gravitational-Wave Observatory) and Virgo detectors.