4 papers
Quasi-holonomy in non-adiabatic quantum evolution
Erik Sjöqvist, Adam Fredriksson
We develop a framework for quasi-holonomy in non-adiabatic quantum time evolution of subspaces along loops in a complex Grassmannian. By factoring the Schrödinger evolution into d…
Separation of quantum time evolution into holonomic and dynamical parts
Adam Fredriksson, Erik Sjöqvist
The issue of separating Schrödinger-type quantum time evolution into a product of holonomic and dynamical parts in the non-adiabatic non-Abelian case is examined. We identify all…
Comment on "Evolution Operator Can Always Be Separated into the Product of Holonomy and Dynamic Operators"
Adam Fredriksson, Erik Sjöqvist
We show that the claim in Ref. [PRL 131, 200202 (2023)], that the quantum time evolution always can be written as a product of a holonomy operator and a dynamic operator, is false,…
Sum rule for non-adiabatic geometric phases
Adam Fredriksson, Erik Sjöqvist
Berry monopoles always cancel when summing over a complete set of energy eigenstates. We demonstrate that analogous sum rules exist for geometric phases and their underlying 2-form…