PT Symmetry Enforced Twin Exchange As the Origin of Chirality-Induced Spin Selectivity

Journal Article · Wed Mar 18 00:00:00 EDT 2026 · Science Advances

DOI:https://doi.org/10.1126/sciadv.aec7069· OSTI ID:3029498

Theiler, Pius ^[1]; Sander, Driessen ^[2]; Beard, Matthew ^[1]

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1. National Laboratory of the Rockies, Golden, CO (United States)
2. Duke University; Eindhoven University of Technology

Chiral molecules, ubiquitous in chemistry and biology, can differentiate electrons by their spin, a phenomenon known as chirality-induced spin selectivity (CISS). Despite its robustness and technological relevance, CISS has resisted conventional explanation: Spin-orbit coupling (SOC) models cannot fully account for the observed magnitude, room-temperature persistence, or equilibrium signatures. Here, we argue that structural chirality enforces a twin-pair exchange mechanism via the indistinguishability principle, which intrinsically couples spin and spatial degrees of freedom such that wave functions cannot be factorized into spin and spatial components. We derive an effective Hamiltonian that describes both transport and equilibrium CISS phenomena and is non-Hermitian. However, the inherent pseudo-Hermiticity, with symmetry as a special case, ensures real eigenvalues and thermodynamic consistency. We demonstrate that our framework is a step toward resolving long-standing anomalies of CISS. It situates CISS alongside equilibrium symmetry-breaking phenomena such as ferromagnetism and superconductivity, with implications for spintronics, catalysis, and the origins of biological homochirality.

• Research Organization: National Laboratory of the Rockies (NLR), Golden, CO (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: AC36-08GO28308
• OSTI ID: 3029498
• Report Number(s): NLR/JA-5900-94817
• Journal Information: Science Advances, Journal Name: Science Advances Journal Issue: 12 Vol. 12
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
59 BASIC BIOLOGICAL SCIENCES
chirality
chirality-induced spin selectivity
exchange correlations
non-Hermitian skin effect
spin