We propose a robust scheme for generating macroscopic superposition states of spin or motion with the aid of a single photon. Shaping the wave packet of the photon enables high-fidelity preparation of nonclassical states of matter even in the presence of photon loss. Success is heralded by photodetection, enabling the scheme to be implemented with a weak coherent field. We analyze applications to preparing Schrödinger cat states of a collective atomic spin or of a mechanical oscillator coupled to an optical resonator. The method generalizes to preparing arbitrary superpositions of coherent states, enabling full quantum control. We illustrate this versatility by showing how to prepare Dicke or Fock states, as well as superpositions in the Dicke or Fock basis.

中文翻译：

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用成形的单光子绘制自旋或运动的非经典状态

我们提出了一种鲁棒的方案，用于借助单个光子生成自旋或运动的宏观叠加状态。形成光子的波包的形状即使在存在光子损失的情况下也可以高保真地准备物质的非经典状态。光电检测预示着成功，这使得该方案可以在弱相干领域中得以实施。我们分析了用于准备集体原子自旋或耦合到光学谐振器的机械振荡器的薛定ding猫状态的应用。该方法概括为准备相干态的任意叠加，从而实现完整的量子控制。我们通过显示如何准备Dicke或Fock状态以及Dicke或Fock基础上的叠加来说明这种多功能性。