High-dimensional quantum process tomography with undetected photons

The goal of quantum process tomography is to fully characterize an operation performed on a quantum state. By considering high-dimensional quantum states (qudit), we show that it is possible to fully reconstruct an arbitrary operation without performing any measurement on the transformed qudit. Our method is interferometric and conceptually different from existing techniques of quantum process tomography that must perform a measurement on the transformed qudit.

Source: arXiv:2608.02490v1 - http://arxiv.org/abs/2608.02490v1 PDF: https://arxiv.org/pdf/2608.02490v1 Original Link: http://arxiv.org/abs/2608.02490v1