High-harmonic generation in semi-Dirac and Weyl semimetals with broken time-reversal symmetry: exploring the case of multiple semi-Dirac points

We investigate Anomalous High-Harmonic Generation (AHHG) within a model undergoing a transition from a Weyl semimetal with broken time-reversal symmetry to a semi-Dirac regime. The latter represents a gapless semimetal with a parabolic dispersion in one direction and conical dispersion in the other two. We highlight the broadening of the distribution of excitations in the Brillouin zone and peaks in the AHHG response, observed as a function of the parameter governing the separation of Weyl nodes, as the frequency of the laser pulse increases. Furthermore, we explain the splitting of these peaks upon an increase in the frequency when multiple semi-Dirac points coexist in the Brillouin zone.