  Time-periodic light field can dress the electronic states and lead to
light-induced emergent properties in quantum materials. While below-gap pumping
is regarded favorable for Floquet engineering, so far direct experimental
evidence of momentum-resolved band renormalization still remains missing. Here,
we report experimental evidence of light-induced band renormalization in black
phosphorus by pumping at photon energy of 160 meV which is far below the band
gap, and the distinction between below-gap pumping and near-resonance pumping
is revealed. Our work demonstrates light-induced band engineering upon
below-gap pumping, and provides insights for extending Floquet engineering to
more quantum materials.
