This study reports the direct experimental observation of Floquet states in monolayer graphene using time- and momentum-resolved photoemission spectroscopy. The researchers used linearly-polarized infrared light to coherently dress the graphene and then probed the resulting band structure with extreme ultraviolet pulses. They identified Floquet sidebands, Volkov sidebands, and their quantum path interference in the photoemission spectral function. The results demonstrate that Floquet engineering in graphene is possible, providing experimental validation for theoretical predictions of Floquet-engineered band structures and topological phases. The study highlights the importance of quantum path interference in distinguishing Floquet sidebands from Volkov sidebands. The findings open new avenues for testing theoretical proposals on light-induced phase transitions in graphene and other quantum materials. The research also shows that the asymmetry in the momentum distribution of the Floquet sidebands can be controlled by varying the polarization of the infrared light, offering a method to study quantum path interference between Floquet and Volkov states. The results confirm the successful generation of Floquet states in graphene and provide a direct experimental verification of Floquet engineering in this material.This study reports the direct experimental observation of Floquet states in monolayer graphene using time- and momentum-resolved photoemission spectroscopy. The researchers used linearly-polarized infrared light to coherently dress the graphene and then probed the resulting band structure with extreme ultraviolet pulses. They identified Floquet sidebands, Volkov sidebands, and their quantum path interference in the photoemission spectral function. The results demonstrate that Floquet engineering in graphene is possible, providing experimental validation for theoretical predictions of Floquet-engineered band structures and topological phases. The study highlights the importance of quantum path interference in distinguishing Floquet sidebands from Volkov sidebands. The findings open new avenues for testing theoretical proposals on light-induced phase transitions in graphene and other quantum materials. The research also shows that the asymmetry in the momentum distribution of the Floquet sidebands can be controlled by varying the polarization of the infrared light, offering a method to study quantum path interference between Floquet and Volkov states. The results confirm the successful generation of Floquet states in graphene and provide a direct experimental verification of Floquet engineering in this material.