  Generation of circularly-polarized high-harmonics with the same helicity to
all orders is indispensable for chiral-sensitive spectroscopy with attosecond
temporal resolution. Solid-state samples have added a valuable asset in
controlling the polarization of emitted harmonics. However, maintaining the
identical helicity of the emitted harmonics to all orders is a daunting task.
In this work, we demonstrate a robust recipe for efficient generation of
circularly-polarized harmonics with the same helicity. For this purpose, a
nontrivial tailored driving field, consisting of two co-rotating laser pulses
with frequencies $\omega$ and $2\omega$, is utilized to generate harmonics from
graphene. The Lissajous figure of the total driving pulse exhibits an absence
of the rotational symmetry, which imposes no constraint on the helicity of the
emitted harmonics. Our approach to generating circularly-polarized harmonics
with the same helicity is robust against various perturbations in the setup,
such as variation in the subcycle phase difference or the intensity ratio of
the $\omega$ and $2\omega$ pulses, as rotational symmetry of the total driving
pulse remains absent. Our approach is expected to be equally applicable to
other two-dimensional materials, among others, transition-metal dichalcogenides
and hexagonal boron nitride as our approach is based on absence of the
rotational symmetry of the driving pulse. Our work paves the way for
establishing compact solid-state chiral-XUV sources, opening a new realm for
chiral light-matter interaction on its intrinsic timescale.
