Understanding and Reducing Thermal Noise via Atomistic Simulations

该奖项是根据2009年《美国复苏和再投资法案》(公法111-5)提供资金的。最先进的第一原理量子力学计算将用于了解Ta2O5等介质涂层的机械性能。机械性能会影响材料中的热噪声，从而限制超高精度干涉仪的性能，如激光干涉仪引力波天文台(LIGO)中使用的干涉仪，或腔稳激光系统的频率稳定性。高级LIGO是LIGO的下一次重大升级，目前正在建设中，预计将受到最关键的50-150赫兹频段的热噪声的限制，而几种最先进的频率稳定系统的性能则受到低至几赫兹频率的热噪声的限制。设计具有所需性能的介质涂层具有普遍的社会意义。所提出的研究活动在许多远超LIGO的高精度光学测量中都有应用，例如时间和频率测量。表征材料的计算方法也将在各种其他领域有用，如纳米科学、材料科学和生物科学。该项目还将为研究生提供计算物理方面的严格培训。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). State-of-the-art first-principles quantum mechanical calculations will be used to understand the mechanical properties of dielectric coatings such as Ta2O5. Mechanical properties affect thermal noise in materials that can limit the performance of ultra high-precision interferometers, such those employed in the Laser Interferometer Gravitational-Wave Observatory (LIGO), or the frequency stability of cavity-stabilized laser systems. Advanced LIGO, the next major upgrade of LIGO now under construction, is expected to be limited by thermal noise in the most critical 50-150 Hz band while the performance of several state-of-the-art frequency stabilization systems is limited by thermal noise at frequencies as low as a few Hz. It is of general, societal importance to design dielectric coatings with desired properties. The proposed research activities have applications in many high precision optical measurements far beyond LIGO, for example, time and frequency measurements. The computational approach that characterizes materials will also be useful in a variety other areas such as nano-scale science, material science, and bio-science. The project will also provide rigorous training for graduate students in computational physics.