Niessen, K. A. et al. Nat. Commun. 10, 1026 (2019).

Anisotropic terahertz microscopy (ATM) offers a spectroscopic signature for measuring intramolecular protein vibrations in the terahertz (THz) frequency range that may be associated with protein functional states. The requirement for sample rotation and maintenance of a relative position with respect to the THz polarization, however, has limited ATM’s applications in studies of biomolecule dynamics. Niessen et al. developed polarization-varying ATM (PV-ATM), which removes the sample-rotation requirement, thus allowing for the rapid resolution of closely spaced resonances. Using the PV-ATM system, they demonstrated the benefits of their method by examining lysozyme-inhibitor binding and by measuring the dynamical fingerprints of benchmarking proteins and RNA G-quadruplex.