• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to project page

2022 Fiscal Year Research-status Report

Interacting topological phases and operator algebras

Research Project

Project/Area Number 19K14548
Research InstitutionTohoku University

Principal Investigator

ボーン クリストファー・ジャック  東北大学, 材料科学高等研究所, 助教 (20830110)

Project Period (FY) 2019-04-01 – 2024-03-31
KeywordsIndex theory / Quantum walk / Topological phases
Outline of Annual Research Achievements

The project has been quite successful in adapting techniques from operator algebras, index theory and noncommutative geometry to certain classes of quantum mechanical Hamiltonians and gapped ground states.

Building from our established framework, we began a systematic study of topological and index theoretic properties of quantum walks, which can be regarded as quantum (discrete) analogues of random walks. In particular, quantum walks are expected to be useful in the implementation of algorithms in quantum computing. Determining robust properties of such quantum walks via a concrete link to topological invariants is therefore of significant value.

We were able to adapt our mathematical techniques in the study of Hamiltonians and gapped ground states to quantum walk systems and define several topologically robust indices. This work has been submitted for publication and is currently under review.

Current Status of Research Progress
Current Status of Research Progress

2: Research has progressed on the whole more than it was originally planned.

Reason

The key expected outcomes and goals of the submitted proposal have largely been accomplished. Robust topological indices have been defined for a large class of Hamiltonians that support a unique gapped ground state. However, due to the COVID pandemic, most of the proposed travel plans have had to be delayed or cancelled. As such, we have extended the project for one more year to further expand upon the project's original goals as well as reschedule delayed travel plans.

Strategy for Future Research Activity

Our new results on topological phases of quantum walks provide a strong starting point to further explore new and novel connections between index theory and operator algebras with quantum information theory.
As a first step in this direction, our aim is to characterise quantum walks with additional anti-linear symmetries such as charge-conjugation symmetry. We also aim to study quantum walks that arise from periodically driven systems and their connection with secondary invariants.

Causes of Carryover

The ongoing COVID pandemic has continued to affect our ability to carry out our travel plans. Most of the allotted budget for the KAKENHI has been spent and the remaining will be used in FY2023.

Remarks

Personal academic webpage
https://sites.google.com/site/khomologyzone/home

  • Research Products

    (6 results)

All 2023 2022 Other

All Int'l Joint Research (2 results) Journal Article (1 results) (of which Int'l Joint Research: 1 results,  Peer Reviewed: 1 results) Presentation (3 results) (of which Int'l Joint Research: 2 results,  Invited: 3 results)

  • [Int'l Joint Research] Leiden University(オランダ)

    • Country Name
      NETHERLANDS
    • Counterpart Institution
      Leiden University
  • [Int'l Joint Research] Australian National University/University of Wollongong(オーストラリア)

    • Country Name
      AUSTRALIA
    • Counterpart Institution
      Australian National University/University of Wollongong
  • [Journal Article] Locally equivalent quasifree states and index theory2022

    • Author(s)
      Chris Bourne
    • Journal Title

      Journal of Physics A: Mathematical and Theoretical

      Volume: 55 Pages: 104004~104004

    • DOI

      10.1088/1751-8121/ac508b

    • Peer Reviewed / Int'l Joint Research
  • [Presentation] Index theory and topological phases for symmetric quantum walks2023

    • Author(s)
      Chris Bourne
    • Organizer
      CREST Research Seminar on "Theoretical studies of topological phases of matter"
    • Invited
  • [Presentation] Split-step quantum walks, chiral unitaries and K-theory2022

    • Author(s)
      Chris Bourne
    • Organizer
      University of Wollongong Operator Algebras and Noncommutative Geometry Seminar
    • Int'l Joint Research / Invited
  • [Presentation] Fermionic gapped ground states, topological phases and index theory2022

    • Author(s)
      Chris Bourne
    • Organizer
      Winter School and Conference on Noncommutative Geometry and Geometric Analysis
    • Int'l Joint Research / Invited

URL: 

Published: 2023-12-25  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi