Journal article icon

Journal article

Free fermions beyond Jordan and Wigner

Abstract:
The Jordan-Wigner transformation is frequently utilised to rewrite quantum spin chains in terms of fermionic operators. When the resulting Hamiltonian is bilinear in these fermions, i.e. the fermions are free, the exact spectrum follows from the eigenvalues of a matrix whose size grows only linearly with the volume of the system. However, several Hamiltonians that do not admit a Jordan-Wigner transformation to fermion bilinears still have the same type of free-fermion spectra. The spectra of such "free fermions in disguise" models can be found exactly by an intricate but explicit construction of the raising and lowering operators. We generalise the methods further to find a family of such spin chains. We compute the exact spectrum, and generalise an elegant graph-theory construction. We also explain how this family admits an N=2 lattice supersymmetry.
Publication status:
Published
Peer review status:
Peer reviewed

Actions


Access Document


Files:
Publisher copy:
10.21468/SciPostPhys.16.4.102

Authors


More by this author
Institution:
University of Oxford
Division:
MPLS
Department:
Physics
Sub department:
Theoretical Physics
Oxford college:
All Souls College
Role:
Author


Publisher:
SciPost
Journal:
SciPost Physics More from this journal
Volume:
16
Issue:
4
Article number:
102
Publication date:
2024-04-10
Acceptance date:
2024-03-25
DOI:
EISSN:
2542-4653


Language:
English
Pubs id:
1989035
Local pid:
pubs:1989035
Deposit date:
2024-04-10

Terms of use



Views and Downloads






If you are the owner of this record, you can report an update to it here: Report update to this record

TO TOP