论文标题
线性光学元件超过50％的成功概率的钟形测量
Bell-state measurement exceeding 50% success probability with linear optics
论文作者
论文摘要
钟形的预测是当今大多数量子通信和计算协议的基本基础。但是，使用基于线性光学的当前钟形测量方案，只能确定四个钟状态中的两个，这意味着此重要步骤的最大成功概率不能超过$ 50 \％\％$。在这里，我们在实验上证明了一种以辅助光子形式修改原始测量的方案，这导致了更复杂的测量模式，最终更高的成功概率为$ 62.5 \％$。在实验上，我们实现了$（57.9 \ pm 1.4）\％$的成功概率，比传统方案的显着改善。有可能将方案扩展到大量的辅助光子，我们的工作为基于铃铛测量值的量子技术实现更有效地实现铺平了道路。
Bell-state projections serve as a fundamental basis for most quantum communication and computing protocols today. However, with current Bell-state measurement schemes based on linear optics, only two of four Bell states can be identified, which means that the maximum success probability of this vital step cannot exceed $50\%$. Here, we experimentally demonstrate a scheme that amends the original measurement with additional modes in the form of ancillary photons, which leads to a more complex measurement pattern, and ultimately a higher success probability of $62.5\%$. Experimentally, we achieve a success probability of $(57.9 \pm 1.4)\%$, a significant improvement over the conventional scheme. With the possibility of extending the protocol to a larger number of ancillary photons, our work paves the way towards more efficient realisations of quantum technologies based on Bell-state measurements.
