{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T03:16:50Z","timestamp":1775186210378,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2025,1,28]],"date-time":"2025-01-28T00:00:00Z","timestamp":1738022400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German Research Foundation DFG","award":["449119662"],"award-info":[{"award-number":["449119662"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>While billiard systems of various shapes have been used as paradigmatic model systems in the fields of nonlinear dynamics and quantum chaos, few studies have investigated anisotropic billiards. Motivated by the tremendous advances in using and controlling electronic and optical mesoscopic systems with bilayer graphene (BLG), representing an easily accessible anisotropic material for electrons when trigonal warping is present, we investigate billiards of various anisotropies and geometries using a trajectory-tracing approach founded on the concept of ray\u2013wave correspondence. We find that the presence of anisotropy can change the billiards\u2019 dynamics dramatically from its isotropic counterpart. It may induce chaotic and mixed dynamics in otherwise integrable systems and may stabilize originally unstable trajectories. We characterize the dynamics of anisotropic billiards in real and phase space using Lyapunov exponents and the Poincar\u00e9 surface of section as phase space representation.<\/jats:p>","DOI":"10.3390\/sym17020202","type":"journal-article","created":{"date-parts":[[2025,1,28]],"date-time":"2025-01-28T06:47:29Z","timestamp":1738046849000},"page":"202","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Complex Dynamics in Circular and Deformed Bilayer Graphene-Inspired Billiards with Anisotropy and Strain"],"prefix":"10.3390","volume":"17","author":[{"given":"Lukas","family":"Seemann","sequence":"first","affiliation":[{"name":"Institute of Physics, Technische Universit\u00e4t Chemnitz, D-09107 Chemnitz, Germany"}]},{"given":"Jana","family":"Lukin","sequence":"additional","affiliation":[{"name":"Institute of Physics, Technische Universit\u00e4t Chemnitz, D-09107 Chemnitz, Germany"}]},{"given":"Max","family":"H\u00e4\u00dfler","sequence":"additional","affiliation":[{"name":"Institute of Physics, Technische Universit\u00e4t Chemnitz, D-09107 Chemnitz, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0455-1945","authenticated-orcid":false,"given":"Sibylle","family":"Gemming","sequence":"additional","affiliation":[{"name":"Institute of Physics, Technische Universit\u00e4t Chemnitz, D-09107 Chemnitz, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0596-6982","authenticated-orcid":false,"given":"Martina","family":"Hentschel","sequence":"additional","affiliation":[{"name":"Institute of Physics, Technische Universit\u00e4t Chemnitz, D-09107 Chemnitz, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Akkermans, E., and Montambaux, G. 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