Optical Tamm state aided room-temperature amplified spontaneous emission from carbon quantum dots embedded one-dimensional photonic crystals

Optical Tamm state (OTS) aided room-temperature amplified spontaneous emission (ASE) from carbon quantum dots (CQDs) embedded all-dielectric one-dimensional photonic crystals (1DPhCs) is presented. 1DPhCs, constituting twelve pairs of alternating quarter wave thick SiO₂ and TiO₂ thin films are fabricated by sol-gel synthesis route. The 1DPhCs are covered with ∼50 nm thick silver thin film to obtain the Tamm structures. CQDs are prepared using organic precursors (onion pulp) and incorporated in the TiO₂ matrix of the final four pairs of the 1DPhCs. OTSs are observed in the reflection spectra at a detection angle of ∼15°, at ∼648 nm and ∼618 nm, for the samples with and without CQDs respectively. Comparisons of enhancement of photoluminescence from samples with and without CQDs are presented. ASE at ∼648 nm corresponding to the OTS of the CQDs incorporated Tamm structure, and suppression of emission within the photonic stop-band is demonstrated. (paper)