Chirality, Spin Coherence and Entanglement in Quantum Biology

Chirality, Spin Coherence and Entanglement in Quantum Biology Chirality, Spin Coherence and Entanglement in Quantum Biology Scientists from Arizona State University, Northwestern, and UCLA explore fundamental quantum effects in biological systems. They use predictive theory and advanced spectroscopic, magnetic, and local probe techniques to elucidate the fundamental mechanisms by which molecular chirality and spin polarization influence electron motion within biological molecules in a two-pronged approach. First, they develop electron donor-bridge-acceptor (D-B-A) systems in which D, B, and/or A are chiral with a complement of time-resolved optical and electron paramagnetic resonance spectroscopy and spin-polarized scanning tunneling microscopy to determine how chirality influences the electronic, vibrational, and spin degrees of freedom controlling ET from photoexcited donors to acceptor sites as spin-coherent entangled electron-hole (e/h) pairs are generated. Second, they use synthetic enantiomeric pairs of DNA hairpins with tailored electron donors and acceptors as part of their structures to probe chirality-dependent ET on model biological systems. Both systems are characterized as a function of D-A distance, temperature, redox properties, and coupling to their surrounding environment. Since most biological molecules, including amino acids in proteins and nucleotides in RNA and DNA, are chiral, the roles of spin polarization in electron transport within and between biological molecules, which are critical to their function, will be determined. In addition to studying the unexplored roles of spin coherence in quantum biology, how it can coexist with spin polarization and how or if it can create entangled states will be addressed. The goal of this proposal is to answer these questions, which are central to and underpin the emerging field of quantum biology.