  Pulse shaping is important for communications, spectroscopy, and other
applications that require high peak power and pulsed operation, such as radar
systems. Unfortunately, pulse shaping remains largely elusive for terahertz
(THz) frequencies. To address this void, a comprehensive study on the
dispersion tunability properties of THz chirped pulses traveling through a
dielectric-lined hollow-core waveguide loaded with a helical graphene ribbon is
presented.
