| Project Detail |
The quantum mechanical simulation of time-dependent (TD) phenomena is relevant for many technological and medical applications, as in solar cells design, control of radiation damage in biomolecules, photocatalysis, nanoscale conductance devices, and quantum computers.
With this proposal, the candidate intends to overcome the most critical limitations of current methods for the calculation of electronic dynamics - most notably of TD Density Functional Theory (DFT) - by pioneering a combination of (1) innovative density functional approximations and (2) an algorithm for time-propagation that treats one electron semi-classically.
The common thread linking these parts is the so-called exact factorization, an overarching strategy that has been used by both the candidate and the supervisor in the contexts of DFT and molecular dynamics (MD), respectively. According to this strategy, the wavefunction is rewritten as a product of a “marginal” and a “conditional” amplitude and the corresponding Schrödinger equation is conveniently expanded into two coupled equations, providing a clear decomposition of the chemical environment.
Joining together the candidates expertise in fundamental DFT and the supervisor’s expertise in trajectory-based approaches, the algorithm that will be developed takes inspiration from the method elaborated by the host for ab initio MD simulations and adapts and supplements it in a way suitable to treat the motion of electrons. The project includes validation of the algorithm on simple electronic structures (simple atoms/molecules), whose static and dynamical densities and potentials are computationally accessible and can serve as benchmark.
The end goal of the project is to develop a reliable and computationally practical method for the simulation of ultrafast processes that can support and complement the emergent experimental techniques (attosecond spectroscopy), particularly for those cases for which present TDDFT or alternative approaches fail. |
