  Revealing the fine electronic structure is critical for understanding the
underlying physics of low-dimensional materials. Angle-resolved photoemission
spectroscopy (ARPES) is a powerful experimental technique for mapping out the
experimental electronic structure. By reducing the photon energy (e.g. to 6 eV)
using laser sources, a greatly improved momentum resolution can be achieved,
thereby providing opportunities for ``zooming in'' the fine electronic
structure and even revealing the previously unresolvable bands near the
Brillouin zone center. Here, by using quasi-one-dimensional material CuTe as an
example, we demonstrate the unique capability of laser-based ARPES in revealing
the fine electronic structures of ``hidden'' charge density wave induced shadow
bands near the Brillouin zone center, which are previously unresolvable using
synchrotron sources. The observation of the shadow bands reveals the CDW phase
from the aspect of band folding, and the unpredicted CDW band hybridization
strongly modifies the electronic structure and Fermi surface, which suggests
that such hybridization must be taken into account for studying the CDW
transition. Moreover, the ultrafast non-equilibrium carrier dynamics are
captured by time-resolved ARPES, revealing the relaxation dynamics through
electron-phonon scattering. Our work demonstrates the advantages of laser-based
ARPES in zooming in the fine electronic structures, as well as capturing the
ultrafast dynamics of low-dimensional materials.
