Quantum technologies hold great promise for revolutionizing photonic applications such as cryptography. Yet, their implementation in real-world scenarios is challenging, mostly because of sensitivity of quantum correlations to scattering. Recent developments in optimizing the shape of single photons introduce new ways to control entangled photons. Nevertheless, shaping single photons in real time remains a challenge due to the weak associated signals, which are too noisy for optimization processes. Here, we overcome this challenge and control scattering of entangled photons by shaping the classical laser beam that stimulates their creation. We discover that because the classical beam and the entangled photons follow the same path, the strong classical signal can be used for optimizing the weak quantum signal. We show that this approach can increase the length of free-space turbulent quantum links by up to two orders of magnitude, opening the door for using wavefront shaping for quantum communications.

量子技术为密码学等光子应用带来革命性的变革。然而，它们在现实世界场景中的实施具有挑战性，主要是因为量子相关性对散射的敏感性。优化单光子形状的最新进展引入了控制纠缠光子的新方法。然而，由于相关信号较弱，实时塑造单光子仍然是一个挑战，这些信号对于优化过程来说噪音太大。在这里，我们克服了这一挑战，并通过塑造刺激纠缠光子产生的经典激光束来控制纠缠光子的散射。我们发现，由于经典光束和纠缠光子遵循相同的路径，因此强经典信号可以用于优化弱量子信号。我们证明，这种方法可以将自由空间湍流量子链路的长度增加多达两个数量级，为使用波前整形进行量子通信打开了大门。