Quantum Computation and Information Seminar 

17/04/2009, 15:00 — 16:00 — Room P4.35, Mathematics Building
Pedro Ribeiro, CFIF, IST-TULisbon

Adiabatic Quantum Computation and Quantum Phase Transitions - Static and Dynamic features of two toy models

We have proposed a simple model which highlights the relations between quantum phase transitions and adiabatic (quantum) computation. This model puts in evidence the importance of the choice of the initial Hamiltonian and of the adiabatic path in the parameter space; it should be helpful as a toy model for more realistic cases. We have also studied the state populations dynamics when a quantum phase transition point is crossed, for the LMG model studied in the first part. Numerical simulations show that the dynamics of the populations is very sensitive to the presence of exceptional points in the spectrum, which a simplified model for the quantum evolution already suggests.