Optical microcavities based on distributed Bragg reflectors (DBRs) are essential platforms for the investigation of light-matter interactions. These structures consist of a periodic stacking of dielectric materials’ bilayers with different refractive indexes that give rise to light frequencies whose propagation is forbidden within the structure. These frequencies are commonly known as photonic bandgaps (PBGs).1 When a defect layer is introduced within the lattice it generates cavity modes, specific frequencies in the PBG where light can propagate.1 Traditionally, DBRs are fabricated using inorganic dielectric materials. However, fully polymeric microcavities offer a compelling alternative due to their ease of fabrication, flexibility and compatibility with solution-based processing techniques.2 In this work, we report the fabrication and optical characterization of fully polymeric DBR microcavities composed of alternating layers of poly(N-vinylcarbazole) (PVK) and Aquivion® (AQ), embedding a defect layer formed by 1,1’-disulfobutyl-3,3’-diethyl-5,5’,6,6’-tetrachlorobenzimidazolylcarbocyanine sodium salt (TDBC) J-aggregates dispersed in a poly(vinyl alcohol) (PVA) matrix. J-aggregates are investigated due to their narrow absorption and emission linewidths, high oscillator strengths, and well-defined excitonic transitions, making them interesting candidates for achieving strong light-matter interaction.3 The multilayers were fabricated by spin-coating, obtaining films with high optical quality. Angle-resolved reflectance and transmittance measurements were performed, revealing the formation of a strong light-matter interaction known as strong coupling. This phenomenon occurs when the excitons and the confined photons interact coherently, leading to the formation of hybrid light-matter states known as polaritons.4 Comparative studies with samples, either without the TDBC layer or using cellulose acetate instead of AQ, highlight the importance of both the narrow-band excitonic emitter and high dielectric contrast in achieving the strong coupling regime. These results demonstrate the potential of fully polymeric microcavities as flexible platforms for future applications in photonic devices, such as ultra-low threshold lasers.
Strong coupling in fully polymeric optical microcavities incorporating TDBC J-Aggregates
Di Fonzo Daniela;Lanfranchi Andrea;Lova Paola;Comoretto Davide
2025-01-01
Abstract
Optical microcavities based on distributed Bragg reflectors (DBRs) are essential platforms for the investigation of light-matter interactions. These structures consist of a periodic stacking of dielectric materials’ bilayers with different refractive indexes that give rise to light frequencies whose propagation is forbidden within the structure. These frequencies are commonly known as photonic bandgaps (PBGs).1 When a defect layer is introduced within the lattice it generates cavity modes, specific frequencies in the PBG where light can propagate.1 Traditionally, DBRs are fabricated using inorganic dielectric materials. However, fully polymeric microcavities offer a compelling alternative due to their ease of fabrication, flexibility and compatibility with solution-based processing techniques.2 In this work, we report the fabrication and optical characterization of fully polymeric DBR microcavities composed of alternating layers of poly(N-vinylcarbazole) (PVK) and Aquivion® (AQ), embedding a defect layer formed by 1,1’-disulfobutyl-3,3’-diethyl-5,5’,6,6’-tetrachlorobenzimidazolylcarbocyanine sodium salt (TDBC) J-aggregates dispersed in a poly(vinyl alcohol) (PVA) matrix. J-aggregates are investigated due to their narrow absorption and emission linewidths, high oscillator strengths, and well-defined excitonic transitions, making them interesting candidates for achieving strong light-matter interaction.3 The multilayers were fabricated by spin-coating, obtaining films with high optical quality. Angle-resolved reflectance and transmittance measurements were performed, revealing the formation of a strong light-matter interaction known as strong coupling. This phenomenon occurs when the excitons and the confined photons interact coherently, leading to the formation of hybrid light-matter states known as polaritons.4 Comparative studies with samples, either without the TDBC layer or using cellulose acetate instead of AQ, highlight the importance of both the narrow-band excitonic emitter and high dielectric contrast in achieving the strong coupling regime. These results demonstrate the potential of fully polymeric microcavities as flexible platforms for future applications in photonic devices, such as ultra-low threshold lasers.
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
