The 45° wire-grid polariser used in the VNA-CD measurement.

Introducing quasi-optical terahertz circular dichroism spectroscopy

Junyi Qui, Yang Zeng, Richard Pickersgill, Robert S. Donnan, Oleksandr Ju. Sushko, Bin Yang


A sub-Terahertz circular dichroism spectrometer is developed and built based on a vector network analyzer driven quasi-optical system at 220-325 GHz sub-THz frequency domain (VNA-CD). The main goal is to explore the potentially significant absorption features in THz signatures of aqueous protein samples.


sub-Terahertz; circular dichroism; absorption; protein structural change


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