Controlling the Manifold of Polariton States Through Molecular Disorder

George, Aleesha; Geraghty, Trevor; Kelsey, Zahra; Mukherjee, Soham; Davidova, Gloria; Kim, Woojae; Musser, Andrew J

doi:10.1002/adom.202302387

Cited by 7 publications

(1 citation statement)

References 70 publications

(138 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although different schemes are invoked to verify strong-coupling, for very broad/disordered molecular systems, such as MC, the condition Ω R > |Γ c – Γ MC | most closely matches secondary measures of strong coupling . Our system is therefore well within the strong-coupling regime at the onset of ultrastrong coupling (Ω R > 0.2 E 0 = 450 meV, where E 0 = 2.25 eV is the uncoupled molecular transition energy), although the validity of such analysis for ultrastrong coupling in highly disordered molecular systems is debated …”

Section: Resultsmentioning

confidence: 99%

Controlling Molecular Photoisomerization in Photonic Cavities through Polariton Funneling

Lee,

Melton,

et al. 2024

J. Am. Chem. Soc.

View full text Add to dashboard Cite

Strong coupling between photonic modes and molecular electronic excitations, creating hybrid light-matter states called polaritons, is an attractive avenue for controlling chemical reactions. Nevertheless, experimental demonstrations of polaritonmodified chemical reactions remain sparse. Here, we demonstrate modified photoisomerization kinetics of merocyanine and diarylethene by coupling the reactant's optical transition with photonic microcavity modes. We leverage broadband Fourier-plane optical microscopy to noninvasively and rapidly monitor photoisomerization within microcavities, enabling systematic investigation of chemical kinetics for different cavity-exciton detunings and photoexcitation conditions. We demonstrate three distinct effects of cavity coupling: first, a renormalization of the photonic density of states, akin to a Purcell effect, leads to enhanced absorption and isomerization rates at certain wavelengths, notably red-shifting the onset of photoisomerization. This effect is present under both strong and weak light-matter couplings. Second, kinetic competition between polariton localization into reactive molecular states and cavity losses leads to a suppression of the photoisomerization yield. Finally, our key result is that in reaction mixtures with multiple reactant isomers, exhibiting partially overlapping optical transitions and distinct isomerization pathways, the cavity resonance can be tuned to funnel photoexcitations into specific reactant isomers. Thus, upon decoherence, polaritons localize into a chosen isomer, selectively triggering the latter's photoisomerization despite initially being delocalized across all isomers. This result suggests that careful tuning of the cavity resonance is a promising avenue to steer chemical reactions and enhance product selectivity in reaction mixtures.

show abstract

Section: Resultsmentioning

confidence: 99%

Controlling Molecular Photoisomerization in Photonic Cavities through Polariton Funneling

Lee,

Melton,

et al. 2024

J. Am. Chem. Soc.

View full text Add to dashboard Cite

show abstract

Thermal disorder prevents the suppression of ultra-fast photochemistry in the strong light-matter coupling regime

Dutta,

Tiainen,

Sokolovskii

et al. 2024

Nat Commun

View full text Add to dashboard Cite

Strong coupling between molecules and confined light modes of optical cavities to form polaritons can alter photochemistry, but the origin of this effect remains largely unknown. While theoretical models suggest a suppression of photochemistry due to the formation of new polaritonic potential energy surfaces, many of these models do not account for the energetic disorder among the molecules, which is unavoidable at ambient conditions. Here, we combine simulations and experiments to show that for an ultra-fast photochemical reaction such thermal disorder prevents the modification of the potential energy surface and that suppression is due to radiative decay of the lossy cavity modes. We also show that the excitation spectrum under strong coupling is a product of the excitation spectrum of the bare molecules and the absorption spectrum of the molecule-cavity system, suggesting that polaritons can act as gateways for channeling an excitation into a molecule, which then reacts normally. Our results therefore imply that strong coupling provides a means to tune the action spectrum of a molecule, rather than to change the reaction.Placing molecules between the mirrors of a Fabry-Pérot micro-cavity that is resonant with their excitation frequency, has been shown to alter their chemistry in both ground and excited states 1-9 , but the origin of these effects is hitherto unknown. Inside the cavity, the rate of energy exchange between excitations of the molecules and confined light modes of the cavity can exceed the intrinsic decay rates of both the molecular excitations and the photonic modes 10 . Under these conditions, the system enters the strong light-matter coupling regime, in which the excitations of the molecules hybridize with the confined light modes of the cavity to form new light-matter states, called polaritons [11][12][13][14] .Changes to photo-chemical reactivity have been rationalized on the basis of differences between the potential energy surfaces of the polariton and that of the bare molecule, as illustrated in Fig. 1c 15 . The key to this hypothesis is that the lifetime of the polariton is sufficiently long for the reactants to evolve over the modified portions of the potential energy surface. Despite recent suggestions that the lowestenergy polariton state can be very long-lived 16 , polariton lifetimes are generally considered to be limited by the lifetime of the cavity photon 17,18 , which is on the order of a few tens of femtoseconds in the metallic cavities that have been used in experiments. Because the polariton decay rate in these experiments was significantly higher than

show abstract

Embrace the darkness: An experimental perspective on organic exciton–polaritons

Khazanov,

Gunasekaran,

George

et al. 2023

Chemical Physics Reviews

View full text Add to dashboard Cite

Organic polaritonics has emerged as a captivating interdisciplinary field that marries the complexities of organic photophysics with the fundamental principles of quantum optics. By harnessing strong light–matter coupling in organic materials, exciton–polaritons offer unique opportunities for advanced device performance, including enhanced energy transport and low-threshold lasing, as well as new functionalities like polariton chemistry. In this review, we delve into the foundational principles of exciton–polaritons from an experimental perspective, highlighting the key states, processes, and timescales that govern polariton phenomena. Our review centers on the spectroscopy of exciton–polaritons. We overview the primary spectroscopic approaches that reveal polariton phenomena, and we discuss the challenges in disentangling polaritonic signatures from spectral artifacts. We discuss how organic materials, due to their complex photophysics and disordered nature, not only present challenges to the conventional polariton models but also provide opportunities for new physics, like manipulating dark electronic states. As the research field continues to grow, with increasingly complex materials and devices, this review serves as a valuable introductory guide for researchers navigating the intricate landscape of organic polaritonics.

show abstract

Controlling the Manifold of Polariton States Through Molecular Disorder

Cited by 7 publications

References 70 publications

Controlling Molecular Photoisomerization in Photonic Cavities through Polariton Funneling

Controlling Molecular Photoisomerization in Photonic Cavities through Polariton Funneling

Thermal disorder prevents the suppression of ultra-fast photochemistry in the strong light-matter coupling regime

Embrace the darkness: An experimental perspective on organic exciton–polaritons

Contact Info

Product

Resources

About