Department of Physics, Stanford University, Stanford, California 94305, USA.
Department of Applied Physics, Stanford University, Stanford, California 94305, USA.
Phys Rev Lett. 2018 Sep 21;121(12):123602. doi: 10.1103/PhysRevLett.121.123602.
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.
我们提出了一种利用单光子产生自旋或运动的宏观叠加态的鲁棒方案。通过对光子的波包进行整形，可以在存在光子损耗的情况下，实现非经典物质态的高保真制备。通过光探测来宣告成功，从而使该方案能够用弱相干场来实现。我们分析了将集体原子自旋或机械振子与光腔耦合的薛定谔猫态制备的应用。该方法推广到了相干态的任意叠加的制备，实现了完全的量子控制。我们通过展示如何制备狄克或福克态以及狄克或福克基中的叠加态，来说明这种多功能性。
