Coherent dynamics in broken symmetry phases

Chatterjee, Abhinava (2019) Coherent dynamics in broken symmetry phases. Masters thesis, Indian Institute of Science Education and Research Kolkata.

[img] PDF (MS dissertation of Abhinava Chatterjee (14MS098))
14MS098.pdf - Submitted Version
Restricted to Repository staff only

Download (999kB)
Official URL:


In this thesis, we outline the dynamics of symmetry broken phases particularly related to condensation phenomena. The thesis is primarily divided into parts - in the first part, Kerr frequency combs in the driven nonlinear Schrödinger equation are obtained in the form of a fractional transform, involving sinusoidal functions. This exactly connects the periodic solution space of this non-integrable system with that of the linear harmonic oscillator. The solutions are found in two distinct classes, corresponding to the presence and absence of a background condensate. The latter case is characterized by a unique solution, while the former shows a rich phase space offering parametric control over the frequency space comb. In the second part of the thesis, we study the topological properties of magnon excitations in a S = 1=2 Heisenberg antiferromagnet on a bilayer honeycomb lattice with strong interlayer coupling complemented by layer restricted Dzyaloshinskii-Moriya (DM) interactions. Our goal is to investigate the BEC of field-induced triplon excitations on the ground state. The presence of the DM term in the Hamiltonian introduces a gap in the energy bands. We calculate the topological number associated with the triplon bands and the corresponding effects of the band structure on physical observables.

Item Type: Thesis (Masters)
Additional Information: Supervisor: Prof. Prasanta K. Panigrahi; Co-supervisor: Prof. Pinaki Sengupta
Uncontrolled Keywords: BEC; Bose-Eisntein Condensation; Broken Symmetry; Coherent Dynamics; Topological BEC
Subjects: Q Science > QC Physics
Divisions: Department of Physical Sciences
Depositing User: IISER Kolkata Librarian
Date Deposited: 14 Feb 2020 07:55
Last Modified: 14 Feb 2020 07:56

Actions (login required)

View Item View Item