Berry connection induced anomalous wave-packet dynamics in non-Hermitian systems

Non - classical effects in wave packet dynamics

This is to certify that the thesis titled Non-classical effects in wave packet dynamics, submitted by C. Sudheesh to the Indian Institute of Technology Madras for the award of the degree of Doctor of Philosophy, is a bona fide record of the research work done by him under our supervision. The contents of this thesis, in full or in part, have not been submitted to any other Institute or Universi...

Noncommutative geometry and nonabelian Berry phase in the wave-packet dynamics of Bloch electrons

Motivated by a recent proposal on the possibility of observing a monopole in the band structure, and by an increasing interest on the role of Berry phase in spintronics, we studied the adiabatic motion of a wave packet of Bloch functions, under a perturbation varying slowly and incommensurately to the lattice structure. We show, using only the fundamental principles of quantum mechanics, that t...

Fictitious-Time Wave-Packet Dynamics in Atomic Systems

Gaussian wave packets (GWPs) are well suited as basis functions to describe the time evolution of arbitrary wave functions in systems with non-singular smooth potentials. They are rare in atomic systems on account of the singular behaviour of the Coulomb potential. We present a time-dependent variational method that makes the use of GWPs possible in the description of propagation of quantum sta...

Wave packet dynamics in atomic systems and Bose - Einstein condensates

Mechanisms of Auger-induced chemistry derived from wave packet dynamics.

To understand how core ionization and subsequent Auger decay lead to bond breaking in large systems, we simulate the wave packet dynamics of electrons in the hydrogenated diamond nanoparticle C(197)H(112). We find that surface core ionizations cause emission of carbon fragments and protons through a direct Auger mechanism, whereas deeper core ionizations cause hydrides to be emitted from the su...