The calculation of quantum canonical time correlation functions is considered in this paper. Transport properties, such as diffusion and reaction rate coefficients, can be determined from time integrals of these correlation functions. Approximate, quantum-classical expressions for correlation functions, which are amenable to simulation, are derived. These expressions incorporate the full quantu...

1. INTRODUCTION In the quantum computational framework there are polynomial time solving algorithms, for problems having exponential classical solutions. The quest is – on one hand – to search if there are other possible effective quantum algorithms and – on the other hand – to be able to produce efficient implementations for the already known algorithms. The most feasible implementation of qua...

We present a quantum-classical hybrid algorithm that simulates electronic structures of periodic systems such as ground states and quasiparticle band structures. By extending the unitary coupled cluster (UCC) theory to describe crystals in arbitrary dimensions, for hydrogen chain, we numerically demonstrate UCC ansatz implemented on quantum circuit can be successfully optimized with small devia...