New opportunities for imaging chiral nuclear dynamics in chiral molecules on ultrafast time scales with synthetic chiral light
ORAL
Abstract
Chiral molecules exist in pairs of left- and right-handed enantiomers. These “mirror twins” behave identically unless they interact with another chiral “object”. Distinguishing them is vital, but also hard [1]. Traditional optical methods rely on the helical structure that circularly polarized light draws in space. However, the pitch of this helix is too large, which leads to weak enantio-sensitivity (usually below 0.1%) and poses major challenges for imaging chiral dynamics, especially on ultrafast time scales.
Synthetic chiral light [2,3] allows us to bypass this fundamental limitation by encoding chirality in time, rather than relying on the spatial helix of circularly polarized light. Such light is locally chiral: the tip of the electric-field vector draws a chiral (3D) Lissajous figure in time, at every point in space. It produces giant enantio-sensitivity (100%) at the level of total intensity signals [2]. We have also shown that light's local handedness can be structured in space to realize a chiral double-slit experiment that leads to enantio-sensitive light bending [3].
Here we show how to exploit the giant enantio-sensitivity enabled by synthetic chiral light to probe chiral nuclear rearrangements during chemical reactions in a highly enantio-sensitive manner. Using time-dependent density functional theory, we explore how the nonlinear response of the prototypical chiral molecule H2O2 changes as a function of its dihedral angle, which defines its handedness. The direct mapping between chiral dichroism and nuclear geometry provides a way of probing chiral nuclear dynamics at their natural time scales. Our work paves the way for ultrafast and highly efficient imaging of enantio-sensitive dynamics in complex chiral systems, including biologically relevant molecules.
[1] Berova et al, Comprehensive Chiroptical Spectroscopy (Wiley, 2013)
[2] Ayuso et al, Nat Photon 13, 866 (2019)
[3] Ayuso et al, Nat Commun 12, 3951 (2021)
[4] Ayuso, arXiv:2111.13671 (2021)
Synthetic chiral light [2,3] allows us to bypass this fundamental limitation by encoding chirality in time, rather than relying on the spatial helix of circularly polarized light. Such light is locally chiral: the tip of the electric-field vector draws a chiral (3D) Lissajous figure in time, at every point in space. It produces giant enantio-sensitivity (100%) at the level of total intensity signals [2]. We have also shown that light's local handedness can be structured in space to realize a chiral double-slit experiment that leads to enantio-sensitive light bending [3].
Here we show how to exploit the giant enantio-sensitivity enabled by synthetic chiral light to probe chiral nuclear rearrangements during chemical reactions in a highly enantio-sensitive manner. Using time-dependent density functional theory, we explore how the nonlinear response of the prototypical chiral molecule H2O2 changes as a function of its dihedral angle, which defines its handedness. The direct mapping between chiral dichroism and nuclear geometry provides a way of probing chiral nuclear dynamics at their natural time scales. Our work paves the way for ultrafast and highly efficient imaging of enantio-sensitive dynamics in complex chiral systems, including biologically relevant molecules.
[1] Berova et al, Comprehensive Chiroptical Spectroscopy (Wiley, 2013)
[2] Ayuso et al, Nat Photon 13, 866 (2019)
[3] Ayuso et al, Nat Commun 12, 3951 (2021)
[4] Ayuso, arXiv:2111.13671 (2021)
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Publication: Ayuso, arXiv:2111.13671 (2021)
Presenters
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David Ayuso
Imperial College London, Department of Physics, Imperial College London, London, UK
Authors
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David Ayuso
Imperial College London, Department of Physics, Imperial College London, London, UK