Related Experiment Video
Updated: Aug 5, 2026

A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Interplay of one- and two-step channels in electrovibrational two-photon absorption
S Polyutov1, I Minkov, F Gel'mukhanov
1Theoretical Chemistry, Roslagstullsbacken 15, Royal Institute of Technology, S-106 91 Stockholm, Sweden. segey@theochem.kth.se
Abstract:
We present a theory of two-photon absorption that addresses the formation of spectral shapes taking the vibrational degrees of freedom into account. The theory is used to rationalize the observed differences between the spectral shapes of one- and two-photon absorption. We find that the main cause of these differences is that the two-step and coherent two-photon spectral bands are different even considering a single final state. Our formalism is applied to the N101 molecule (p-nitro-p'-diphenylamine stilbene), which was recently studied experimentally. Simulations show that the two-step two-photon electrovibrational absorption results in a blue shift of the absorption spectrum in agreement with the measurements.
More Related Videos
Related Concept Videos
π Electron Effects on Chemical Shift: Overview
Interaction of EM Radiation with Matter: Spectroscopy
Molecular Spectroscopy: Absorption and Emission
UV–Vis Spectroscopy: Molecular Electronic Transitions
IR Absorption Frequency: Hybridization
Among the sp, sp2, and sp3 hybridized orbitals, sp orbitals have the maximum s character (50%). Consequently, the electrons are held more closely to the nucleus, resulting in stronger and shorter C–H bonds that stretch at a...
Deactivation Processes: Jablonski Diagram

