New Classes of Blind Quantum Source Separation and Process Tomography Methods Based on Spin Component Measurements Along Two Directions

摘要

We here present major extensions of the fields of blind quantum source separation (BQSS) and blind quantum process tomography (BQPT) for the Heisenberg Hamiltonian. They are based on a new type of spin component measurements performed directly for the available quantum states, which yields new nonlinear mixing models, with extended source signals and mixing parameters. The first two types of proposed BQSS and/or BQPT methods are based on quantum-source independent component analysis. They therefore require typically one thousand quantum states to estimate the mixing parameters, and some of them yield closed-form solutions. We then define a complementary, inversion-based, BQSS/BQPT method which requires only one quantum state, but which is based on solving nonlinear equations numerically.