PHYSICAL REVIEW LETTERS
Evidence for Confined Tamm Plasmon Modes under Metallic Microdisks and Application to the Control of Spontaneous Optical Emission
O. Gazzano, S. Michaelis de Vasconcellos, K. Gauthron, C. Symonds, J. Bloch, P. Voisin, J. Bellessa, A. Lemaître, and P. Senellart
Light can be confined at the interface between a distributed Bragg reflector and 2D metallic layer: the confinement arises, on one side, from the metal’s negative dielectric constant, and on the other side, from the DBR’s stop band.
Here, we show strong three-dimensional confinement of a Tamm plasmon with a very simple microstructure consisting of a thin gold microdisk on top of a planar GaAs/AlGaAs Bragg mirror. The Tamm plasmon (TP), formed at the interface between DBR and metal, is laterally confined to the dimensions of the gold disk, resulting in a discrete mode spectrum with quality factors of up to 1200 .
The modes exhibit a zero in-plane wave vector, allowing for an excellent coupling to quantum dot excitons and the vertical emission of photons. With the in-situ lithography technique, we couple single quantum dots to the confined Tamm plasmon modes. We observe an acceleration of the spontaneous emission if the quantum dot transition is at resonance with the mode, while a remarkably strong inhibition of the spontaneous emission (by a record factor of up to 40) is measured if the quantum dot transition is off-resonance.