  High-harmonic generation has emerged as a pivotal process in strong-field
physics, yielding extreme ultraviolet radiation and attosecond pulses with a
wide range of applications. Furthermore, its emergent connection with the field
of quantum optics has revealed its potential for generating non-classical
states of light. Here, we investigate the process of high-harmonic generation
in semiconductors under a quantum optical perspective while using a Bloch-based
solid-state description. Through the implementation of quantum operations based
on the measurement of high-order harmonics, we demonstrate the generation of
non-classical light states similar to those found when driving atomic systems.
These states are characterized using diverse quantum optical observables and
quantum information measures, showing the influence of electron dynamics on
their properties. Additionally, we analyze the dependence of their features on
solid characteristics such as the dephasing time and crystal orientation, while
also assessing their sensitivity to changes in driving field strength. This
study provides insights into HHG in semiconductors and its potential for
generating non-classical light sources.
