The rapid development of quantum technology has driven the need for high-performance quantum signal processing modules. Balanced homodyne detector (BHD) is one of the most promising options for practical quantum state measurement, providing substantial advantages of cost-effectiveness, no cooling requirement, and system compactness. However, due to the stringent requirements in BHD design, it typically suffers from a relatively small operating bandwidth which limits the overall speed of a quantum system. In this study, we propose comprehensive modelling for the BHD in quantum applications and enhance the performance of BHDs based on our modelling. Specifically, we utilise a photonic chip approach and optimise the electronic design to create the integrated BHD, which significantly boosts the 3 dB bandwidth to 4.75 GHz and achieves a shot-noise-limited bandwidth of 23 GHz. We demonstrate the capability of this setup to generate quantum random numbers at a rate of 240 Gbit s⁻¹, highlighting its potential for ultra-high-speed quantum communication and quantum cryptography applications.

中文翻译：

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一种芯片集成的零差检测系统，具有增强的量子应用带宽性能


量子技术的快速发展带动了对高性能量子信号处理模块的需求。平衡零差探测器 (BHD) 是实用量子态测量最有前途的选择之一，具有成本效益、无需冷却和系统紧凑等显着优势。然而，由于 BHD 设计的严格要求，它通常会遇到相对较小的工作带宽，从而限制了量子系统的整体速度。在这项研究中，我们提出了对量子应用中的 BHD 进行全面建模，并基于我们的建模增强了 BHD 的性能。具体来说，我们利用光子芯片方法并优化电子设计来创建集成 BHD，从而将 3 dB 带宽显着提升至 4.75 GHz，并实现 23 GHz 的散粒噪声限制带宽。我们展示了该设置以 240 Gbit s ^-1的速率生成量子随机数的能力，突显了其在超高速量子通信和量子密码学应用中的潜力。