TICTAC: Turnkey, Inexpensive and Compact Ti:sapphire Astrocomb Concept

TICTAC：交钥匙、廉价且紧凑的钛蓝宝石 Astrocomb 概念

• 批准号: ST/X004503/1
• 负责人: Derryck Reid
• 金额: $ 61.74万
• 依托单位: Heriot-Watt University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FX004503%2F1
• 关键词: TICTAC; Turnkey; Inexpensive; Compact; Ti

In 1929, Edwin Hubble reported that spectra from further away galaxies were more redshifted, providing foundational evidence for the expansion of the universe.Almost 100 years later, some of the most exciting science cases for optical astronomy rely on spectroscopy, including the detection and characterisation of Earth-like exoplanets, and the Sandage Test, which aims to directly measure the acceleration in the expansion of the universe from the temporal variation of the redshift of extra-galactic sources.Astronomers use high resolution spectrographs to record the pattern of colours received from distant objects, but the wavelength axes of these instruments can shift slightly over time, and so must be regularly calibrated with an external reference light source to ensure consistency between observations.For several decades, lamps producing hundreds of narrow atomic emission lines have been used as calibration sources, but the high precision and accuracy demanded by exoplanet and cosmological observations now exceeds their capabilities.In response, the astronomy community is turning to astrocombs, a laser technology giving a sequence of ultra-narrow, drift-free, regularly spaced optical frequencies on a selectable grid spacing of 5-50 GHz. When referenced to GPS time, astrocombs provide atomically traceable optical frequencies with a precision at the 10^-12 level.Current astrocombs are complex and expensive systems, typically costing >2 million EUR, and their limited reliability requires regular maintenance visits by PhD-level staff.Our proposal seeks to address these issues by developing a new, simple and robust laser platform based on diode-pumped Ti:sapphire. The timeliness of this concept is emphasised by letters of support from ESO, and from the HARPS3 and ANDES instrument consortia.A promising proof-of-concept Ti:sapphire laser emerging from Heriot-Watt's current STFC consortium grant will first be systematically optimised to produce the powers and pulse durations needed for an astrocomb system.Using new alignment and mounting techniques developed at Heriot-Watt it will then be developed into a turnkey device, in which the optical elements forming the laser cavity will be bonded directly to a common baseplate, eliminating the drift and instability associated with optomechanical mounts.External partners will provide state-of-the-art nonlinear waveguides to the project, with designs tailored to generate broadband visible light when driven by the developed laser system. Using photonic locking and filtering methods, we will configure this light into the format needed for an astrocomb. The final year of the project will integrate these diverse elements into a single astrocomb system, testing it first on a high resolution comb-mode-resolving spectrograph at Heriot-Watt.We will conclude the project with a campaign at the 10-metre SALT telescope, validating the system outside the lab, as a key step to commercialisation and building community confidence in the performance of this disruptive astrocomb concept.Steps towards commercialisation will be taken during the project including, where appropriate: filing of patent protection, spin-out company incorporation, development of licensing agreements, and input from business development advisors.The project offers excellent value for money, with the £477K cost to STFC being highly leveraged by £187K in-kind support from our partners and £120K cash (20% FEC) from Heriot-Watt.

1929 年，埃德温·哈勃 (Edwin Hubble) 报告称，来自更远星系的光谱红移更为严重，为宇宙膨胀提供了基础证据。 近 100 年后，光学天文学中一些最令人兴奋的科学案例依赖于光谱学，包括探测和表征类地系外行星的研究，以及桑德奇测试，其目的是根据银河系外源红移的时间变化直接测量宇宙膨胀的加速度。天文学家使用高分辨率光谱仪来记录从远处物体接收到的颜色图案，但这些仪器的波长轴可能会随着时间的推移而略有变化，因此必须定期使用外部参考光源进行校准，以确保观测之间的一致性。几十年来，产生数百条窄原子发射线的灯已被用作校准源，但系外行星和宇宙学观测所需的高精度和准确度现在超出了它们的能力。作为回应，天文学界正在转向星梳，这是一种激光技术可选网格间距为 5-50 GHz 的一系列超窄、无漂移、规则间隔的光学频率。当参考 GPS 时间时，星体梳可提供精度为 10^-12 级别的原子可追踪光学频率。 astrocombs 是复杂而昂贵的系统，通常成本超过 200 万欧元，其有限的可靠性需要博士级工作人员进行定期维护访问。我们的提案旨在通过开发一种新型、简单且坚固的激光器来解决这些问题基于二极管泵浦钛蓝宝石的平台 ESO、HARPS3 和 ANDES 仪器联盟的支持信强调了这一概念的及时性。赫瑞瓦特当前出现的一种有前景的概念验证钛蓝宝石激光器。 STFC 财团资助将首先进行系统优化，以产生星体梳系统所需的功率和脉冲持续时间。使用在赫瑞瓦特公司随后将其开发为交钥匙设备，其中形成激光腔的光学元件将直接粘合到公共基板上，从而消除与光机械安装座相关的漂移和不稳定性。外部合作伙伴将提供最先进的技术- 该项目采用先进的非线性波导，其设计可在由所开发的激光系统驱动时产生宽带可见光，我们将把这种光配置成星体梳所需的格式。该项目将把这些不同的元素集成到一个星梳系统中，首先在赫瑞瓦特的高分辨率梳状模式分辨光谱仪上进行测试。我们将在 10 米 SALT 望远镜上进行一次活动，验证该系统在实验室之外，作为商业化的关键一步，并建立社区对这一颠覆性 astrocomb 概念性能的信心。项目期间将采取商业化步骤，包括（在适当情况下）：申请专利保护、分拆公司公司成立、许可协议的制定以及业务发展顾问的投入。该项目物有所值，STFC 的 47.7 万英镑成本通过我们合作伙伴提供的 18.7 万英镑实物支持和 12 万英镑现金（20% FEC ）来自赫瑞瓦特。