Shen Yangchao, Lu Yao, Zhang Kuan, Zhang Junhua, Zhang Shuaining, Huh Joonsuk, Kim Kihwan
Center for Quantum Information , Institute for Interdisciplinary Information Sciences , Tsinghua University , Beijing 100084 , P. R. China . Email:
Department of Chemistry , Sungkyunkwan University , Suwon 16419 , Korea . Email:
Chem Sci. 2017 Dec 1;9(4):836-840. doi: 10.1039/c7sc04602b. eCollection 2018 Jan 28.
Molecules are one of the most demanding quantum systems to be simulated by quantum computers due to their complexity and the emergent role of quantum nature. The recent theoretical proposal of Huh (Nature Photon., 9, 615 (2015)) showed that a multi-photon network with a Gaussian input state can simulate a molecular spectroscopic process. Here, we present the first quantum device that generates a molecular spectroscopic signal with the phonons in a trapped ion system, using SO as an example. In order to perform reliable Gaussian sampling, we develop the essential experimental technology with phonons, which includes the phase-coherent manipulation of displacement, squeezing, and rotation operations with multiple modes in a single realization. The required quantum optical operations are implemented through Raman laser beams. The molecular spectroscopic signal is reconstructed from the collective projection measurements for the two-phonon-mode. Our experimental demonstration will pave the way to large-scale molecular quantum simulations, which are classically intractable, but would be easily verifiable by real molecular spectroscopy.
由于分子的复杂性以及量子特性所起的关键作用，分子是量子计算机模拟的最具挑战性的量子系统之一。Huh最近的理论提议（《自然·光子学》，9，615（2015））表明，具有高斯输入态的多光子网络可以模拟分子光谱过程。在此，我们展示了首个量子装置，它利用被困离子系统中的声子产生分子光谱信号，以SO为例。为了进行可靠的高斯采样，我们开发了声子的关键实验技术，其中包括在单次实现中对多个模式的位移、压缩和旋转操作进行相位相干操纵。所需的量子光学操作通过拉曼激光束实现。分子光谱信号是从双声子模式的集体投影测量中重建的。我们的实验演示将为大规模分子量子模拟铺平道路，这些模拟在经典情况下难以处理，但通过实际分子光谱很容易验证。
