GP2 - Birmingham Workshop Program: Odd elasticity from topological quantum geometry

Session Information

Location: Physics West 103 | School of Physics and Astronomy, University of Birmingham
Day: 1. Tuesday 21st April
Time: 17:00-18:00
Chairperson: N/A

Presentation Details

Presentation Type: Poster | 
Title: Odd elasticity from topological quantum geometry
Abstract: We uncover a class of nonlinear odd viscoelastic effects in three spatial dimensions [arXiv:2511.22706]. We show that these dissipationless effects arise upon combining strains in two orthogonal directions, yielding momentum flow in the third direction. We demonstrate that the effect arises from nontrivial geometric tensors in quantum states, and can be scaled up with integer topological invariants. We further demonstrate that the effect fingerprints the multiband Hilbert-space geometry of underlying quantum states, as encoded in three-state geometric tensors. Our findings unravel the role of multistate geometry in viscoelastic phenomena, paving a path for experimental observation of uncharted nonlinear odd viscoelastic responses in quantum systems.

Further, we show that certain three-dimensional topological phases can act as acoustic diodes realizing nonlinear odd acoustoelastic effects [arXiv:2601.20951]. Beyond uncovering topologically-induced anomalous acoustic second-harmonic generation and rectification, we demonstrate how such nonlinear responses are uniquely captured by the momentum-space nonmetricity tensor in the quantum state Hilbert-space geometry. In addition to completing the classification of quantum geometric observables in the quadratic response regime, our findings reveal unexplored avenues for experimental realizations of acoustic diodes using effective theta vacua of axion insulators adaptable for topological engineering applications

Presenter

Mr Ashwat Jain
University of Manchester | United Kingdom

Authors

1. Jain, Ashwat | University of Manchester
2. Jankowski, Wojciech J. | University of Cambridge
3. Mehraeen, M. | University of Manchester
4. Slager, Robert-Jan | University of Manchester, University of Cambridge