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

Abstract

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.