Superconducting Qubits: Dephasing and Quantum Chemistry
P. J. J. O’Malley · eScholarship (California Digital Library) · 2016
One of the most exciting potential applications of a quantum computer is the abilityto efficiently simulate quantum systems, a task that is out of the reach of even thelargest classical supercomputers. Such simulations require a quantum algorithm capableof efficiently representing and manipulating a quantum system, as well as a device withsufficient coherence to execute it. In this work, we describe experiments advancing bothof these goals. First, we discuss dephasing—currently a leading cause of decoherencein superconducting qubits—and present measurements accurately quantifying both low-and high-frequency phase noise sources. We then discuss two quantum algorithms forthe simulation of chemical Hamiltonians, and experimentally contrast their performance.These results show that with continuing improvement in quantum devices we may soonbe able to apply quantum computers to practical chemistry problems.