Investigations of Thienoacene Molecules for Classical and Entangled Two-Photon Absorption

Abstract

Investigations of the optical effects in thienoacene chromophores with different central atoms were performed. These chromophores provide a basis for the comparison of the linear, two-photon, and entangled two-photon properties in organic molecules with varying degrees of dipolar or quadrupolar character. Linear absorption and emission as well as time-dependent density functional theory calculations were performed for the chromophores investigated. Measurements of the classical two-photon absorption (TPA), entangled two-photon absorption (ETPA), as well as entangled two-photon fluorescence were experimentally performed for the four chromophores. Electronic structure calculations were utilized to provide estimates of the classical two-photon absorption coefficients. The results of the measured entangled two-photon cross sections were compared with theoretical estimates for the molecules investigated. It is found that the dipole (transition or permanent) pathway can have an effect on the trends in the entangled photon absorption process in dipolar organic chromophores. This study helps predict the properties of the entangled twophoton effect in chromophores with different dipolar and quadrupolar character.

An Additivity Scheme for Aromaticity: The Heteroatom Case

“…The results seen here in Figure h now indicate that, for these systems, the aromaticity itself may be predicted, providing even easier access to predicted physical properties of oligomers of this kind (as well as their thiophene‐ and furan‐containing analogues). Thioacenes of the type L7 have been very recently investigated by Goodson and co‐workers for classical and entangled photon absorption, due to their use for nonlinear optical applications. The types of systems investigated in this work are eminently suitable to preliminary screening using our methodology, as they incorporate a limited set of building blocks in various topologies.…”

Entangled light–matter interactions and spectroscopy

“…For example, entangled two-photon absorption has only been studied in a handful of molecular fluorophores. 6,[27][28][29][30][31][32][33] However, the potential applications of entangled light-matter interactions make exploration and application in the materials field an intriguing possibility.…”

“…For example, entangled two-photon absorption has only been studied in a handful of molecular fluorophores. 6,[24][25][26][27][28][29][30] An understanding of this phenomenon, let alone an extensive experimental basis, doesn't exist yet for most condensed matter, low-dimensional materials, and molecular systems. The perspective therefore also provides the technical basis needed to start such experiments in the hopes of broadening a nascent field.…”

Verifying the Survival of Time-Energy Entanglement Through Tissue

“…With such promise, the field of entanglement-enhanced TPA has grown significantly in recent years, focusing on experimentally characterizing the entanglement-enhanced TPA cross sections for various samples in various configurations [12][13][14][15][16][17][18][19][20][21][22]. These works report that the entanglementenhanced cross sections not only depend on the fluorophore, but also on the input-state [8].…”