부산대학교 도서관

The speed limit of quantum state transfer in a system of interacting particles is not only important for quantum information processing, but also directly linked to Lieb-Robinson-type bounds that are crucial for understanding various aspects of quantum many-body physics. For strongly long-range interacting systems such a fully-connected quantum computer, such speed limit is still unknown. Here we develop a new Quantum Brachistochrone method that can incorporate inequality constraints on the Hamiltonian. This method allows us to prove an exactly tight bound on the speed of quantum state transfer on a subclass of Hamiltonians realizable by a fully-connected quantum computer.
Comment: 10 pages