The QUANTIC group has produced the first work on by QUANTIC-only members, Artur Garcia-Saez and Jose Ignacio Latorre, on one of the main research directions of the team: quantum algorithms! The manuscript reference is arxiv:1806.02287
In this work the focus is on improving the performance of the nowadays popular variational quantum eigensolvers, or VQE. These algorithms are hybrid in that they have a classical part and a quantum part. The classical part consists of optimization methods which then influence the parameters of a quantum circuit that eventually produces an estimation of a certain parameter. This parameter is then important to calculate binding energies of molecules, for instance. This is actually one of the most promising real-life problems which quantum computers, even the noisy, small-scale ones existing these days.
With the new algorithm designed in this work, the Adiabatically-Assisted Variational Quantum Eigensolver (AAVQE) a modification of usual VQE is introduced, in which one starts from a trivial Hamiltonian that produces an exact estimation of a certain parameter. This feeds in a second step in which the Hamiltonian is slightly less trivial. Eventually one arrives at the real-problem Hamiltonian but with a set of parameters evolved in such a way that the result of the problem is obtained directly. In their wok, Artur and José Ignacio have been able to show that the AAVQE algorithm works very well for classical problems, unlike the usual VQE, as has been recently stated.