Quantum information transfer between a two-level and a four-level quantum systems

Quantum mechanics provides a disembodied way to transfer quantum information from one object another. In theory, this can occur between objects of any dimension, yet the reported experiments date have mainly focused on cases where same dimension. Here we theoretically propose and experimentally demonstrate scheme for different dimensions.By using an optical qubit-ququart entangling gate, observe two photons with dimensions, including flow four-dimensional photon two-dimensional vice versa.The fidelities range 0.700 0.917, all above classical limit 2/3. Our work sheds light new direction demonstrates our ability implement operations beyond two-level systems.