Ultra-Broadband Waveform Generation Using Actively Stabilized Hybrid Photonic-Electronic Circuits - Phase 2

GOSPEL-2旨在探索、实现和演示一种新的概念，用于在光学或太赫兹频率范围内产生超宽带任意波形，从而克服目前数模转换器(DAC)的局限性。这一概念允许通过对调制到光学频率梳的音调上的光学波形进行相位校正交织来实现传统DAC接口的大规模频谱并行化。在第一个资助期新构思的方案的基础上，我们现在的目标是演示总带宽超过300 GHz的波形生成，并实现在芯片级模块中结合先进的光子集成电路和射频电子设备的集成信号发生器。光学任意波形产生(OAWG)系统的主要概念挑战是不同支路信号的精确相干组合所需的相位控制。在项目的第一阶段，我们构思了一种新的概念来实现这种相位控制，并成功地演示了由两个支路信号合成200 GHz宽的光波形。在下一个供资期间，我们现在希望扩大这一想法，并利用它来实施一个综合信号发生器模块。这将需要先进的光子集成电路，通过新开发的密集宽带射频接口无缝连接到射频驱动器电路。同时，我们将把信号支路的数量从两条增加到四条，提供超过300 GHz的整体带宽。在该项目中，我们将开发一个先进的模型来定量地预测我们的系统的性能，设计和实现底层的光子集成电路和射频结构，实现一个混合集成的光子-电子信号发生器引擎，并通过实验证明该方案用于产生超宽带光波形的可行性。我们将在与这一领域的国际领先小组的合作框架内，进一步探索通过超高速单行载波(UTC)光电二极管将光波形下转换到THz频率范围。基于实验验证的系统量化模型，我们将最终分析我们的方案的带宽可伸缩性，并评估合成具有太赫兹带宽的波形的潜力。我们预计，《福音-2》的内容将对超宽带光电子波形合成领域和光通信领域都具有很高的相关性，在光通信领域，无网格软件定义的光发射机可能允许动态带宽分配。

GOSPEL-2 aims at exploring, implementation and demonstrating a novel concept for generation of ultra-broadband arbitrary waveforms in the optical or the THz frequency range, thus overcoming the limitations of current digital-to-analogue converters (DAC). The concept allows for massive spectral parallelization of conventional DAC interfaces by phase-correct interleaving of optical waveforms that are modulated onto the tones of an optical frequency comb. Building upon newly conceived schemes from the first funding period, we now aim at demonstrating waveform generation with an overall bandwidth of more than 300 GHz and at realizing an integrated signal generator that combines advanced photonic integrated circuits with RF electronics in a chip-scale module. The main conceptual challenge of optical arbitrary waveform generation (OAWG) systems is the phase control required for precise coherent combination of different tributary signals. In the first phase of the project, we conceived a novel concept to realize this phase control and successfully demonstrated the synthesis of a 200 GHz-wide optical waveform from two tributary signals. In the next funding period, we now wish to expand on this idea and utilize it to implement an integrated signal-generator module. This will require advanced photonic integrated circuits that are seamlessly connected to RF driver circuitry through newly developed dense broadband RF interfaces. At the same time, we will increase the number of signal tributaries from two to four, offering an overall bandwidth in excess of 300 GHz. Within the project, we shall develop an advanced model to quantitatively predict the performance of our system, design and implement the underling photonic integrated circuits and RF structures, implement a hybrid integrated photonic-electronic signal generator engine, and experimentally demonstrate the viability of the scheme for generation of ultra-broadband optical waveforms. We will further explore down-conversion of the optical waveforms to the THz frequency range through ultra-fast uni-traveling-carrier (UTC) photodiodes in the framework of a collaboration with an internationally leading group in this area. Based on an experimentally verified quantitative model of our system, we shall finally analyze the bandwidth-scalability of our scheme and evaluate the potential of synthesizing waveforms with THz bandwidths. We expect that the contents of GOSPEL-2 will be of high relevance both for the field of ultra-broadband photonic-electronic waveform synthesis and for the field of optical communications, where grid-less software-defined optical transmitters might allow for dynamic bandwidth allocation.