(EurekaAlert) Researchers around Christian Kokail, Christine Maier und Rick van Bijnen at the Institute of Quantum Optics and Quantum Information (IQOQI) of the Austrian Academy of Sciences have surpassed the narrow former limits constraining analog simulation of quantum systems in a quantum computer. They use a programmable ion trap quantum computer with 20 quantum bits as a quantum coprocessor, in which quantum mechanical calculations that reach the limits of classical computers are outsourced. “We use the best features of both technologies,” explains experimental physicist Christine Maier. “The quantum simulator takes over the computationally complex quantum problems and the classical computer solves the remaining tasks.”
A previously unsolved problem in complex quantum simulations is the verification of the simulation results. “Such calculations can hardly or not at all be checked using classical computers. So how do we check whether the quantum system delivers the right result,” asks the theoretical physicist Christian Kokail. “We have solved this question for the first time by making additional measurements in the quantum system. Based on the results, the quantum machine assesses the quality of the simulation,” explains Kokail.