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1. Engineered chirality of one-dimensional nanowires

   https://doi.org/10.1126/sciadv.adx4761  

   Briggeman, Megan; Mansfield, Elliott; Kombe, Johannes; Damanet, François; Lee, Hyungwoo; Tang, Yuhe; Yu, Muqing; Biswas, Sayanwita; Li, Jianan; Huang, Mengchen; et al (June 2025, Science Advances)

   The origin and function of chirality in DNA, proteins, and other building blocks of life represent a central question in biology. Observations of spin polarization and magnetization associated with electron transport through chiral molecules, known collectively as the chiral induced spin selectivity effect, suggest that chirality improves electron transfer. Using reconfigurable nanoscale control over conductivity at the LaAlO₃/SrTiO₃interface, we create chiral electron potentials that explicitly lack mirror symmetry. Quantum transport measurements on these chiral nanowires reveal enhanced electron pairing persisting to high magnetic fields (up to 18 tesla) and oscillatory transmission resonances as functions of both magnetic field and chemical potential. We interpret these resonances as arising from an engineered axial spin-orbit interaction within the chiral region. The ability to create one-dimensional electron waveguides with this specificity creates opportunities to test, via analog quantum simulation, theories about chirality and spin-polarized electron transport in one-dimensional geometries. 

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2. Direct observation of chirality-induced spin selectivity in electron donor–acceptor molecules

   https://doi.org/10.1126/science.adj5328  

   Eckvahl, Hannah J; Tcyrulnikov, Nikolai A; Chiesa, Alessandro; Bradley, Jillian M; Young, Ryan M; Carretta, Stefano; Krzyaniak, Matthew D; Wasielewski, Michael R (October 2023, Science)

   The role of chirality in determining the spin dynamics of photoinduced electron transfer in donor-acceptor molecules remains an open question. Although chirality-induced spin selectivity (CISS) has been demonstrated in molecules bound to substrates, experimental information about whether this process influences spin dynamics in the molecules themselves is lacking. Here we used time-resolved electron paramagnetic resonance spectroscopy to show that CISS strongly influences the spin dynamics of isolated covalent donor–chiral bridge–acceptor (D-Bχ-A) molecules in which selective photoexcitation of D is followed by two rapid, sequential electron-transfer events to yield D^•+-Bχ-A^•–. Exploiting this phenomenon affords the possibility of using chiral molecular building blocks to control electron spin states in quantum information applications. 

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3. Chirality-Induced Spin Selectivity: An Enabling Technology for Quantum Applications

   https://doi.org/10.1002/adma.202300472  

   Chiesa, A.; Privitera, A.; Macaluso, E.; Mannini, M.; Bittl, R.; Naaman, R.; Wasielewski, M. R.; Sessoli, R.; Carretta, S. (June 2023, Advanced materials)

   Molecular spins are promising building blocks of future quantum technologies thanks to the unparalleled flexibility provided by chemistry, which allows the design of complex structures targeted for specific applications. However, their weak interaction with external stimuli makes it difficult to access their state at the single-molecule level, a fundamental tool for their use, for example, in quantum computing and sensing. Here, an innovative solution exploiting the interplay between chirality and magnetism using the chirality-induced spin selectivity effect on electron transfer processes is foreseen. It is envisioned to use a spin-to-charge conversion mechanism that can be realized by connecting a molecular spin qubit to a dyad where an electron donor and an electron acceptor are linked by a chiral bridge. By numerical simulations based on realistic parameters, it is shown that the chirality-induced spin selectivity effect could enable initialization, manipulation, and single-spin readout of molecular qubits and qudits even at relatively high temperatures. 

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4. Chiral Induced Spin Selectivity and Its Implications for Biological Functions

   https://doi.org/10.1146/annurev-biophys-083021-070400  

   Ron Naaman, Yossi Paltiel (May 2022, Annual review of biophysics)

   Chirality in life has been preserved throughout evolution. It has been assumed that the main function of chirality is its contribution to structural properties. In the past two decades, however, it has been established that chiral molecules possess unique electronic properties. Electrons that pass through chiral molecules, or even charge displacements within a chiral molecule, do so in a manner that depends on the electron’s spin and the molecule’s enantiomeric form. This effect, referred to as chiral induced spin selectivity (CISS), has several important implications for the properties of biosystems. Among these implications, CISS facilitates long-range electron transfer, enhances bio-affinities and enantioselectivity, and enables efficient and selective multi-electron redox processes. In this article, we review the CISS effect and some of its manifestations in biological systems.We argue that chirality is preserved so persistently in biology not only because of its structural effect, but also because of its important function in spin polarizing electrons. 

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5. Unraveling the origin of chirality from plasmonic nanoparticle-protein complexes

   https://doi.org/10.1126/science.aax5415  

   Zhang, Qingfeng; Hernandez, Taylor; Smith, Kyle W.; Hosseini Jebeli, Seyyed Ali; Dai, Alan X.; Warning, Lauren; Baiyasi, Rashad; McCarthy, Lauren A.; Guo, Hua; Chen, Dong-Hua; et al (September 2019, Science)

   Plasmon-coupled circular dichroism has emerged as a promising approach for ultrasensitive detection of biomolecular conformations through coupling between molecular chirality and surface plasmons. Chiral nanoparticle assemblies without chiral molecules present also have large optical activities. We apply single-particle circular differential scattering spectroscopy coupled with electron imaging and simulations to identify both structural chirality of plasmonic aggregates and plasmon-coupled circular dichroism induced by chiral proteins. We establish that both chiral aggregates and just a few proteins in interparticle gaps of achiral assemblies are responsible for the ensemble signal, but single nanoparticles do not contribute. We furthermore find that the protein plays two roles: It transfers chirality to both chiral and achiral plasmonic substrates, and it is also responsible for the chiral three-dimensional assembly of nanorods. Understanding these underlying factors paves the way toward sensing the chirality of single biomolecules. 

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