D'Ariano G M, Lo Presti P
Theoretical Quantum Optics Group, INFM Unità di Pavia, Dipartimento di Fisica "Alessandro Volta," Università di Pavia, Pavia, Italy.
Phys Rev Lett. 2001 May 7;86(19):4195-8. doi: 10.1103/PhysRevLett.86.4195.
Quantum operations describe any state change allowed in quantum mechanics, including the evolution of an open system or the state change due to a measurement. We present a general method based on quantum tomography for measuring experimentally the matrix elements of an arbitrary quantum operation. As input the method needs only a single entangled state. The feasibility of the technique for the electromagnetic field is shown, and the experimental setup is illustrated based on homodyne tomography of a twin beam.
量子操作描述了量子力学中允许的任何状态变化，包括开放系统的演化或测量引起的状态变化。我们提出了一种基于量子层析成像的通用方法，用于通过实验测量任意量子操作的矩阵元。该方法作为输入仅需要一个单纠缠态。展示了该技术对电磁场的可行性，并基于双光束的零差层析成像说明了实验装置。
