A growing demand of data exchange capacity and sensitive monitoring of quality, as well as of environmentally or health-relevant agents is driving scientific research. In this context, harnessing quantum effects at the individual particle level promises exponentially faster computing, fully secure communications and unparalleled sensing capabilities. Nowadays, photonic structures able to guide light propagation can be designed and engineered in order to efficiently collect the radiation of nearby-placed single emitters, and, thanks to the Purcell effect, it is in principle possible to enhance the coupling into a simple dielectric waveguide mode up to 50%.
Single Polyaromathic Hydrocarbons (PAHs) molecules in appropriate host systems coherently interact with light at low temperatures. Such interaction can be controlled at the single photon level when the emitters are efficiently coupled to nanophotonic devices. In such a system, single molecules can play both the role of single photon sources and nonlinear elements, so as to unprecedently enable on-chip single-photon logical gates.
We investigate a simple device consisting of single emitters (Dibenzoterrylene molecules (DBT) hosted in anthracene crystals) placed very close (tens of nanometers) to dielectric waveguides. Due to outstanding photostability, strong dipole transitions in the near-infrared (780 nm), lifetime- limited linewidth of 30 MHz at 3 K temperature and easy manipulation of the thin host matrix, individual DBT molecules are ideal quantum emitters for the envisioned device. We are exploring a number of solutions for the photonic part of the device, in particular we consider different materials (Si3N4 and polymers) together with different geometries. We are working both on the theoretical/simulation side and on the experimental one.
-  Sofia Pazzagli, Pietro Lombardi, Daniele Martella, Maja Colautti, Bruno Tiribilli, Francesco Saverio Cataliotti & Costanza Toninelli. Self-Assembled Nanocrystals of Polycyclic Aromatic Hydrocarbons Show Photostable Single-Photon Emission, ACS Nano (2018).
-  Matz Liebel, Costanza Toninelli & Niek F. van Hulst. Room-temperature ultrafast nonlinear spectroscopy of a single molecule, Nature Photonics (2017).
-  P. E. Lombardi, A. P. Ovvyan, S. Pazzagli,G. Mazzamuto, G. Kewes, O. Neitzke, N. Gruhler, O. Benson, W.H.P. Pernice, F. S. Cataliotti, and C. Toninelli. Photostable Molecules on Chip: Integrated Sources of Nonclassical Light, ACS Photonics (2017).
-  Günter Kewes, Max Schoengen, Oliver Neitzke, Pietro Lombardi, Rolf-Simon Schönfeld, Giacomo Mazzamuto, Andreas W. Schell, Jürgen Probst, Janik Wolters, Bernd Löchel, Costanza Toninelli and Oliver Benson. A realistic fabrication and design concept for quantum gates based on single emitters integrated in plasmonic-dielectric waveguide structures, Scientific Reports 6, Article number: 28877 (2016).
-  G. Mazzamuto, A. Tabani, S. Pazzagli, S. Rizvi, A. Reserbat-Plantey, K. Schädler, G. Navickaite, L. Gaudreau, F. S. Cataliotti, F. Koppens and C. Toninelli. Single-molecule study for a graphene-based nano-position sensor, New Journal of Physics, 16 113007, 4 Nov 2014.
-  C. Toninelli, K. Early, J. Bremi, A. Renn, S. Götzinger, and V. Sandoghdar. Near-infrared single-photons from aligned molecules in ultrathin crystalline films at room temperature, Optics Express, Vol. 18, Issue 7, pp. 6577-6582 (2010).