Wave-dispersed two-photon absorption of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">C</mml:mi></mml:mrow><mml:mrow><mml:mn>60</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>

We report the two-photon absorption (TPA) spectrum of ${\mathrm{C}}_{60}$ in the wavelength range \ensuremath{\lambda}=0.7--1.5 \ensuremath{\mu}m. The TPA coefficient \ensuremath{\beta} of the polycrystalline film shows a broad peak, with \ensuremath{\beta}\ensuremath{\approx}25 cm/GW, around 0.95 \ensuremath{\mu}m and drops below 3 cm/GW at \ensuremath{\lambda}&gt;1.2 \ensuremath{\mu}m. We find that the nonlinear absorption, and also the sign of the nonlinear refraction above and below the TPA maximum, are satisfactorily accounted for by modeling the response with a two-photon state positioned at 2.58 eV.

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