We theoretically study the nonlinear electron dynamics of Haldane model quantum dots placed in the field of an ultrashort optical pulse. One of the tuning parameters of the Haldane model is the phase accumulated by an electron during its transfer between the next-nearest-neighbor sites. We study how this parameter affects the nonlinear electron dynamics and the generation of high optical harmonics. With increasing the phase from its zero value to ${90}^{\circ }$, the low-energy electron states in the conduction and valence bands become more localized near the edges of the quantum dot, resulting in suppression of the band gap, enhancement of the dipole interband coupling, and strong suppression of the average low-energy electron density of the states. As a result, the nonlinear response of the electron system of a Haldane model quantum dot is the strongest at intermediate values of the phase, $\approx 30\text{–}{40}^{\circ }$. At these values of the phase, the electron dynamics is irreversible and a few first high-order harmonics have the largest intensities. When the phase approaches a ${90}^{\circ }$ value, the generation of high harmonics is strongly suppressed.

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• High-order harmonic generation
• Nonlinear optics
• Ultrashort pulses
• Graphene
• Quantum dots
• Topological materials