title: Visible-Near-Infrared Range Whispering Gallery Resonance from Photonic μ-Sphere Cavities Self-Assembled from a Blend of Polystyrene and Poly[4,7-bis(3-octylthiophene-2-yl)benzothiadiazole-co-2,6-bis(pyrazolyl)pyridine] Coordinated to Tb(acac)3.
abstract: A novel red emitting copolymer (P1) was prepared (Mn ∼ 10.7 kDa) by copolymerizing tridentate ligand, namely 2,6-bis(pyrazolyl)pyridine (BPP) with 4,7-bis(2-ethynyl-5-thienyl)-2,1,3-benzothiadiazole. This copolymer readily formed an orange yellow emitting metal containing conjugated polymer (P1.Tb) with Tb(acac)3. Further, a judicial blend of P1.Tb with polystyrene and its subsequent self-assembly in THF/water produced microspheres with smooth surface area. Interestingly, continuous wave laser excitation of a single microsphere displayed whispering-gallery-mode (WGM) resonance modes over a broad wavelength range covering visible (Vis) and near-infrared (NIR) regions (0.550-0.875 μm). The estimated Q factor was up to 700, which is very high for a metal containing conjugated polymer (MCCP)-based optical gain medium.
authors.affiliation: Functional Molecular Nano-/Micro-Solids Laboratory, School of Chemistry, and §School of Physics, University of Hyderabad , Prof. C. R. Rao Road, Gachibowli, Hyderabad 500046, India.
authors.forename: Yemineni S L V
authors.initials: YS
authors.lastname: Narayana
authors.affiliation: Functional Molecular Nano-/Micro-Solids Laboratory, School of Chemistry, and §School of Physics, University of Hyderabad , Prof. C. R. Rao Road, Gachibowli, Hyderabad 500046, India.
authors.forename: Dasari
authors.initials: D
authors.lastname: Venkatakrishnarao
authors.affiliation: Functional Molecular Nano-/Micro-Solids Laboratory, School of Chemistry, and §School of Physics, University of Hyderabad , Prof. C. R. Rao Road, Gachibowli, Hyderabad 500046, India.
authors.forename: Arani
authors.initials: A
authors.lastname: Biswas
authors.affiliation: Functional Molecular Nano-/Micro-Solids Laboratory, School of Chemistry, and §School of Physics, University of Hyderabad , Prof. C. R. Rao Road, Gachibowli, Hyderabad 500046, India.
authors.forename: Mahamad Ahamad
authors.initials: MA
authors.lastname: Mohiddon
authors.affiliation: Functional Molecular Nano-/Micro-Solids Laboratory, School of Chemistry, and §School of Physics, University of Hyderabad , Prof. C. R. Rao Road, Gachibowli, Hyderabad 500046, India.
authors.forename: Nirmal
authors.initials: N
authors.lastname: Viswanathan
authors.affiliation: Functional Molecular Nano-/Micro-Solids Laboratory, School of Chemistry, and §School of Physics, University of Hyderabad , Prof. C. R. Rao Road, Gachibowli, Hyderabad 500046, India.
authors.forename: Rajadurai
authors.initials: R
authors.lastname: Chandrasekar
keywords: WGM resonators; metallo-polymers; near-infrared emission; polystyrene; self-assembly