Dirac mass induced by optical gain and loss

Letian Yu, Haoran Xue, Ruixiang Guo, Eng Aik Chan, Yun Yong Terh, Cesare Soci (), Baile Zhang () and Y. D. Chong ()
Additional contact information
Letian Yu: Nanyang Technological University
Haoran Xue: The Chinese University of Hong Kong
Ruixiang Guo: Nanyang Technological University
Eng Aik Chan: Nanyang Technological University
Yun Yong Terh: Nanyang Technological University
Cesare Soci: Nanyang Technological University
Baile Zhang: Nanyang Technological University
Y. D. Chong: Nanyang Technological University

Nature, 2024, vol. 632, issue 8023, 63-68

Abstract: Abstract Mass is commonly considered an intrinsic property of matter, but modern physics reveals particle masses to have complex origins1, such as the Higgs mechanism in high-energy physics2,3. In crystal lattices such as graphene, relativistic Dirac particles can exist as low-energy quasiparticles4 with masses imparted by lattice symmetry-breaking perturbations5–8. These mass-generating mechanisms all assume Hermiticity, or the conservation of energy in detail. Using a photonic synthetic lattice, we show experimentally that Dirac masses can be generated by means of non-Hermitian perturbations based on optical gain and loss. We then explore how the spacetime engineering of the gain and loss-induced Dirac mass affects the quasiparticles. As we show, the quasiparticles undergo Klein tunnelling at spatial boundaries, but a local breaking of a non-Hermitian symmetry can produce a new flux non-conservation effect at the domain walls. At a temporal boundary that abruptly flips the sign of the Dirac mass, we observe a variant of the time-reflection phenomenon: in the non-relativistic limit, the Dirac quasiparticle reverses its velocity, whereas in the relativistic limit, the original velocity is retained.

Date: 2024
References: Add references at CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
https://www.nature.com/articles/s41586-024-07664-x Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:632:y:2024:i:8023:d:10.1038_s41586-024-07664-x

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/s41586-024-07664-x

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().