Mechanically modulated spin orbit couplings in oligopeptides

Abstract

Recently experiments have shown very significant spin activity in biological molecules such as DNA, proteins, oligopeptides and aminoacids. Such molecules have in common their chiral structure, time reversal symmetry and the absence of magnetic exchange interactions. The spin activity is then assumed to be due to either the pure Spin-orbit (SO) interaction or SO coupled to the presence of strong local sources of electric fields. Here we derive an analytical tight-binding Hamiltonian model for Oligopeptides that contemplates both intrinsic SO and Rashba interaction induced by hydrogen bond. We use a lowest order perturbation theory band folding scheme and derive the reciprocal space intrinsic and Rashba type Hamiltonian terms to evaluate the spin activity of the oligopeptide and its dependence of molecule uniaxial deformations. SO strengths in the tens of meV are found and explicit spin active deformation potentials. We find a rich interplay between responses to deformations both to enhance and diminish SO strength that allow for experimental testing of the orbital model. Qualitative consistency with recent experiments shows the role of hydrogen bonding in spin activity.

9 pages, 4 figures

References in corpus (8)

• Quantum Spin Hall Effect in Graphene
• The electronic properties of bilayer graphene
• Spin-orbit coupling in curved graphene, fullerenes, nanotubes, and nanotube caps
• Chiral molecular films as electron polarizers and polarization modulators
• Spin-Dependent Electron Transmission Model for Chiral Molecules in Mesoscopic Devices
• Spin-orbit interaction and spin selectivity for tunneling electron transfer in DNA
• Intrinsic Rashba coupling due to Hydrogen bonding in DNA
• Unveiled electric profiles within hydrogen bonds suggest DNA base pairs with similar bond strengths

Cited by in corpus (4)

• A Chirality-Based Quantum Leap
• Optoelectronic manifestation of orbital angular momentum driven by chiral hopping in helical Se chains
• Dynamical theory of chiral-induced spin selectivity in electron donor-chiral molecule-acceptor systems
• Merging of Dirac points through uniaxial modulation on an optical lattice