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·哈勃报告说，来自更远星系的光谱红移更大，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，以及Sandage测试，天文学家利用高解析度摄谱仪记录从遥远天体接收到的颜色图案，但是这些仪器的波长轴会随着时间的推移而略微偏移，因此必须用外部参考光源定期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一直被用作校准源，但系外行星和宇宙学观测所要求的高精度和准确度现在超过了他们的能力。作为回应，天文学界正在转向天体梳，一种激光技术，提供一系列超窄，无漂移，在5-50 GHz的可选网格间距上规则间隔的光频率。当参考GPS时间时，天文梳提供原子可追踪的光学频率，精度为10^-12级。目前的天文梳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人员定期维护。我们的建议旨在通过开发一种新的，简单而坚固的基于二极管泵浦钛：蓝宝石的激光平台来解决这些问题。ESO以及HARPS 3和安第斯山脉仪器联盟的支持信强调了这一概念的及时性。蓝宝石激光器是由赫瑞瓦特公司目前的STFC财团资助的，它将首先被系统地优化，以产生天文梳系统所需的功率和脉冲持续时间。利用赫瑞瓦特公司开发的新的对准和安装技术，它将被开发成一个交钥匙设备，其中形成激光腔的光学元件将直接粘合到一个公共基板上，外部合作伙伴将为该项目提供最先进的非线性波导，其设计可在开发的激光系统驱动下产生宽带可见光。使用光子锁定和过滤方法，我们将把这种光配置成天文梳所需的格式。该项目的最后一年将把这些不同的元素整合到一个单一的天文梳系统中，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望远镜上完成一项活动，在实验室外验证该系统，作为商业化的关键一步，并建立社区对这一颠覆性的天文梳概念的信心。在项目期间将进行商业化，适当时包括：申请专利保护、成立衍生公司、制定许可协议，以及业务发展顾问的意见。该项目物超所值，STFC的47.7万英镑成本由我们的合作伙伴提供的18.7万英镑实物支持和Heriot-Watt提供的12万英镑现金（20% FEC）高度杠杆化。