California State University, Northridge WordmarkOviatt Library WordmarkOviatt Library Catalog Wordmark
Author Spalding, Jon, author.
Title Exploring quantum phases of the zig-zag chain / by Jon Spalding.
Published [Northridge, California] : California State University, Northridge, 2013.
 Electronic Book  QC30 .Z95 2013 S63eb    ONLINE
Description 1 online resource (v, 39 pages) : illustrations, some color.
Content Type text
still image
Format online resource
File Characteristics text file PDF
Thesis M.S. California State University, Northridge 2013.
Bibliography Includes bibliographical references (pages 37-39).
Note Description based on online resource; title from PDF title page (viewed on Aug. 6, 2013).
Summary The spin liquid quantum mechanical state is at the forefront of condensed matter physics and motivates these introductory studies into quantum magnetism on a one-dimensional spin chain. After reviewing some context and history, the approach (exact diagonalization) and the model (Heisenberg Hamiltonian in one dimension with nearest neighbor (nn), next-nearest neighbor (nnn), and a four-site interaction known as a ring exchange (ring)) are described with simple examples for the reader to study. Methods of observation of quantum spin chains are reviewed, including the structure factor which is an important observable. The entanglement entropy is discussed and demonstrated with hand examples. Then, the structure factor is used to demonstrate a phase transition in a Heisenberg model with only nearest neighbor and next-nearest neighbor interactions. Entanglement entropy is used to investigate and compare rectangular and triangular ladders (nn and nnn with and without ring). Entanglement entropy is used to create a surface plot phase diagram for a nn, nnn, ring model for a wide range of interaction energies. Proposals for future studies are presented in the conclusions, including varied boundary conditions, implementing larger system sizes, and investigating interesting regions of the entropy phase diagram, among other possibilities.
Subject Quantum theory.
Condensed matter.
Heisenberg uncertainty principle.
Quantum entanglement.
Local Subject Dissertations, Academic -- CSUN -- Physics and Astronomy.
OCLC number 855545311