发表机构
Delft University of Technology; Universidade Estadual de Campinas (UNICAMP)（代尔夫特理工大学; 坎皮纳斯州立大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究在毫开尔文温度下的光机械晶体中，实现了接近单量子水平的高效低噪声光子-声子态转移，创纪录的转换效率达0.76，为量子信息处理提供了重要接口
AI 中文摘要
光学光子与机械激发之间的相干接口为声子态工程和混合量子信息处理提供了有前景的途径。腔光机械系统通过光力诱导透明（OMIT）实现此类接口，可实现传输光场与局域机械模式之间的相干映射。然而，由于室温工作及相应的热机械噪声，先前的OMIT转换协议实现仅适用于具有大相干态光子数的经典输入信号。在此，我们展示了在毫开尔文温度下工作的光机械晶体中，接近单量子区域的高效低噪声光子-声子态转移。使用少光子水平的弱相干光输入脉冲，我们实现了创纪录的光子-声子转换效率η=0.76、机械存储寿命T₁=7.3 μs，以及超过4.5 MHz的可调转换带宽。对 retrieved 信号的Hanbury Brown-Twiss测量证实了转换后的声子态的相干性，证明了转换过程中添加的热噪声较低（n_th=9.0）。这些结果确立了光机械晶体作为面向GHz机械模式的高效光学接口的地位，并为确定性单量子水平机械态的制备提供了途径。
英文摘要
Coherent interfaces between optical photons and mechanical excitations provide a promising route towards phonon-state engineering and hybrid quantum information processing. Cavity optomechanical systems enable such interfaces via optomechanically induced transparency (OMIT), allowing coherent mapping between traveling optical fields and localized mechanical modes. However, previous implementations of OMIT conversion protocols were limited to classical input signals with large coherent state photon numbers due to room temperature operation and corresponding thermal mechanical noise. Here, we demonstrate efficient low-noise photon-phonon state transfer close to the single-quantum regime in an optomechanical crystal operated at Millikelvin temperatures. Using weak coherent optical input pulses at the few-photon level, we achieve a record-level photon-phonon conversion efficiency of $η=0.76$, a mechanical storage lifetime of $T_\mathrm{1}=7.3~μs$, and a tunable conversion bandwidth exceeding 4.5 MHz. Hanbury Brown-Twiss measurements of the retrieved signal demonstrate the coherent nature of the converted phononic state, evidencing low added thermal noise in the conversion process ($n_\mathrm{th}=9.0$). These results establish optomechanical crystals as efficient optical interfaces to GHz mechanical modes and provide a pathway toward deterministic single-quantum-level mechanical state preparation.
