Modular Ultrafast Sources

自从1990年第一台克尔透镜锁模激光器问世以来，各种构型的实用飞秒激光器已经为许多重大科学发展带来了丰厚的成果。必须认识到，应用空间仍然受到当前一代超快激光器的成本、复杂性、熟练用户要求和有限的灵活性的限制。在这个拟议的联合项目中，我们寻求在开发新一代超快激光方面处于领先地位。通过采用模块化方法进行激光器设计，我们的目标是展示一个平台，在该平台上可以设计激光器以满足广泛的用户特定要求。例如，通过采用这种方法，用于通信的激光器将具有必要的高重复频率和低峰值功率，而对于生物光子学，将提供高峰值功率，以充分利用可利用的光学非线性。我们计划使用块状和波导型的振动晶体和半导体量子点结构作为主要的增益介质。虽然振动晶体在超短脉冲激光器中得到了广泛的应用，但传统的激光器设计提供的灵活性是非常有限的。为了纠正这种情况，我们打算对腔体设计进行革命性的改革，以实现对激光输出参数的电气控制。例如，我们希望为用户提供一种方法，使用户只需轻轻一按开关，就可以从未锁定状态转换到飞秒脉冲状态。此外，通过利用振动晶体中的波导性，我们有信心推出新一代高度紧凑的激光器，它将结合半导体激光器的许多优点和基于晶体的设备最吸引人的特征。在超快光子学合作的一些初步工作中，我们展示了半导体量子点结构作为宽带增益介质的潜力，可以支持飞秒光脉冲的放大和产生。我们现在寻求在这些有希望的结果的基础上，推动真正灵活的超快激光器，这种激光器将服从外部对增益和损耗组件的电子控制。技术进步有望带来新一代激光器，其兼容性将远远超过传统激光系统设计。在这一战略中，我们计划采用混合方法，将半导体激光器的优点与晶体的能量存储能力相结合，以提供具有覆盖一系列持续时间、能量和轮廓的脉冲特性的紧凑和坚固的源。该项目的主要工作将致力于开发超快激光的控制功能。其目的是使用腔内组件的直接电气控制来提供脉冲整形、调制数据流、波长调谐和定制色散的设计者选项。为了确保这项研究适用，我们将在一组确定的示威者的背景下评估激光的发展。这些实施将被用来展示设计灵活性如何为生物、医疗、通信和相关应用提供优化的激光。我们已经组建了一个研究团队，他们拥有互补的专业知识和在光子学方面的国际卓越记录。该项目作为一个整体将由圣安德鲁斯大学管理，但所有三个研究小组都将对激光发展的所有方面进行互动研究。我们相信，这个团队的工作将代表尖端的基础和翻译研究，它应该代表着英国在开发新的超快激光方面的世界领先力量。

Since the development of the first Kerr-lens mode-locked lasers in 1990, practical femtosecond lasers in a wide variety of configurations have delivered handsomely to a significant number of major scientific developments. It has to be recognised that the application space remains limited by the cost, complexity, skilled-user requirements and restricted flexibility of the current generation of ultrafast lasers. In this proposed joint project we seek to lead the way in the development of a new generation of ultrafast lasers. By adopting a modular approach for laser design we am aiming to demonstrate a platform from which lasers can be designed to address a wide range of user-specific requirements. By taking this approach, lasers for use in communications, for example, will have the necessary high repetition rates and low peak powers whereas for biophotonics high peak powers will be delivered to take full advantage of exploitable optical nonlinearities. We plan to work with vibronic crystals in both bulk and waveguide geometries and semiconductor quantum dot structures as the primary gain media. Although vibronic crystals have been deployed widely in ultrashort-pulse lasers the flexibility offered by conventional laser designs is very limited. To remedy this situation we intend to revolutionise cavity design to enable electrical control of the laser output parameters. For example, we wish to provide a means to users to change from an unmodelocked status to a femtosecond-pulse regime at the flick of switch. Also, by exploiting waveguiding in the vibronic crystals we are confident that we can introduce a new generation of highly compact lasers that will combine many of the advantages of a semiconductor laser with the most attractive features of crystal based devices. In some preliminary work in the Ultrafast Photonics Collaboration we have shown the potential of semiconductor quantum dot structures as broadband gain media that Can support the amplification and generation of femtosecond optical pulses. We now seek to build on those promising results and make the push towards truly flexible ultrafast lasers that will be amenable to external electronic control of the gain and loss components. Progress is expected to lead to a new generation of lasers that can give applications compatibility that far exceeds that available in traditional laser system designs. Within this strategy we plan to employ hybrid approaches where the benefits of semiconductor lasers will be combined with the energy storage capabilities of crystals to deliver compact and rugged sources having pulse characteristics that cover a range of durations, energies and profiles.A major part of this project effort will be devoted to the development of control functionality in ultrafast lasers. The intention is to use direct electrical control of intracavity components to deliver designer options for pulse shaping, modulated data streams, wavelength tuning and tailored dispersion. To ensure that this research is applicable we will evaluate the laser developments in the context of a set of identified demonstrators. These implementations will be used to show how design flexibility can deliver optimised lasers for biological, medical, communications and related applications.We have put together a research team having complementary of expertise and established track records of international excellence in photonics. This project as a whole will be managed from St Andrews University but all three research groups will undertake interactive research on all aspects of the laser development. We are confident that the work of this team will represent cutting-edge fundamental and translational research and it should represent a world leading strength for the UK in the development of new ultrafast lasers.