Quantum optics 43 Quantum theory 34 article 33 Topology 21 Photons 20 Ground state 19 Hamiltonians 18 Quantum entanglement 18 Qubits 18 Density functional theory 16 Quantum chemistry 16 Dynamics 15 Electronic structure 15 Graphene 14 Measurements of 14 Property 14 'current 13 Two-dimensional 12 Atoms 11 Binary alloys 11 Calculations 11 Hermitians 11 Bosons 10 Electronic.structure 10 Energy 10 Monte Carlo methods 10 Quantum computers 10 Stochastic systems 10 Computation theory 9 Condition 9