Description
Implementing the time evolution under a desired target Hamiltonian is critical for various applications in quantum science. Due to the exponential increase of parameters in the system size and due to experimental imperfections, this task can be challenging in quantum many-body settings.
We introduce an efficient and robust scheme to engineer arbitrary local many-body Hamiltonians. This is achieved by applying single-qubit π or π/2 pulses to an always-on system Hamiltonian, which we assume to be native to a given platform. These sequences are constructed by solving an efficient linear program (LP) which minimizes the total evolution time. In this way, we can engineer target Hamiltonians that are only limited by the locality of the interactions in the system Hamiltonian. Based on average Hamiltonian theory and by using robust composite pulses, we make our schemes robust against errors, including finite pulse time errors and various control errors. Finally, we demonstrate the performance of our scheme with numerical simulations for various examples, including systems Hamiltonians with all-to-all connectivity motivated by ion traps and with a 2D square lattice connectivity.
