# Geometric phases for finite-dimensional systems -- the roles of Bargmann Invariants, Null Phase Curves and the Schwinger Majorana SU(2) framework

## TL;DR

This paper investigates the properties of Bargmann Invariants and Null Phase Curves in finite-dimensional quantum systems, utilizing the Majorana theorem and Schwinger framework to develop new operator methods for understanding geometric phases.

## Contribution

It combines the Majorana theorem with Schwinger oscillator methods to create efficient operator-based approaches for analyzing geometric phases in finite-dimensional systems.

## Key findings

- Analysis of algebraic properties of BI using group theory
- Extension of BI-geometric phase connection with NPCs
- Proposals for new experiments in geometric phase studies

## Abstract

We present a study of the properties of Bargmann Invariants (BI) and Null Phase Curves (NPC) in the theory of the geometric phase for finite dimensional systems. A recent suggestion to exploit the Majorana theorem on symmetric SU(2) multispinors is combined with the Schwinger oscillator operator construction to develop efficient operator based methods to handle these problems. The BI is described using intrinsic unitary invariant angle parameters, whose algebraic properties as functions of Hilbert space dimension are analysed using elegant group theoretic methods. The BI-geometric phase connection, extended by the use of NPC's, is explored in detail, and interesting new experiments in this subject are pointed out.