Maximization of the Uhlmann–Jozsa Fidelity for an Open Two-Level Quantum System with Coherent and Incoherent Controls
Oleg Vasilevich Morzhin, Alexander Nikolaevich Pechen · Physics of Particles and Nuclei · 2020
Abstract In the paper, the problem of maximization of the Uhlmann–Jozsa fidelity, which shows the degree of coincidence between the given target density matrix and the final density matrix of a two-level open quantum system exposed to a simultaneous action of coherent and incoherent controls, is considered. For some initial and target density matrices, it was shown analytically that the zero coherent and incoherent controls are singular controls that satisfy the second order necessary conditions for the optimality. In the general case, a numerical method with reduction to finite-dimensional optimization is considered. Numerical results were obtained and presented.