## 1 Introduction  
BSWs show a high quality factor and extreme sensitivity to surface perturbations combined with an easy fabrication process. Thanks to these properties, BSWs are naturally suited for label-free, fluorescence sensing applications, and, in this context, they have widely expressed their capability in the last decades [1; 2; 3; 4; 5; 6; 7]. Moreover, recent papers have investigated their potentialities for on-chip guiding and manipulation of an optical signal propagating on a 1D photonic crystal [8; 9; 10; 11; 12; 13; 14]. Several studies have followed the lead of the first seminal paper on Bloch surface wave guided modes [8], engineering the top layer of the distributed Bragg reflector (DBR) stack to achieve optical manipulation of the in-plane propagating BSW. The opening of an in-plane optical bandgap [15], surface refraction [16],focusing and sub-wavelength focusing [9; 13], and the static manipulation of optical signals [12; 14] have been demonstrated in the last years, based on 2D surface optical elements. However, all these papers show a static modification of the in-plane propagating signal and, consequently, any logic operation--which necessary involves a dynamic manipulation--is prevented. In this context, optical non-linearity has proven to be a powerful tool for achieving logic operations, both in bare optical and exciton-polariton systems [17; 18; 19; 20; 21; 22]. Exciton-polaritons are quasi-particles arising from the strong coupling between excitons and photons and they behave as interacting composite bosons thanks to their half-excitonic nature. The polariton-polariton interactions--which are responsible for the Kerr non-linearity--have been used for the realization of switching [22; 23], interferometers [24], and logic gates [25]. All these works have been performed at cryogenic temperatures (<10 k) in order to prevent Wannier-Mott exciton dissociation (typical of the III-V semiconductors involved in these experiments). In order to get towards realistic applications, we have investigated the possibility of strongly coupling a Bloch surface wave with Frenkel excitons, which are stable at room temperature thanks to their huge binding energy. The resulting Bloch surface wave polaritons (BSWPs) manifest very high speed (>100 um/ps)--arising from their half-photon nature--and, consequently, macroscopic in-plane propagations. Furthermore, we have experimentally demonstrated the blueshift of the mode eigenenergies when increasing the polariton density, laying the first essential stone for the room-temperature polariton logic device's realization. On the other hand, on-chip integration obviously requires an integrated source. Apart from the Frenkel exciton emission observed in BSWP, the integration of sources exhibiting peculiar optical and/or optoelectronic properties is tickling a new generation of optoelectronic devices [26; 27; 28; 29; 30]. In this context, transition metal dichalcogenide (TMDC) monolayers and bilayers have attracted an extraordinary interest in the scientific community over the last decade [28]. This research has led to the realization of photoresistors [31], transistors [32], ultrasensitive photodetectors [33], and biosensors [34], and the demonstration of the optical control of valley polarization towards spintronic devices [35; 36]. The paper is organized into two main sections. In the first part, we demonstrate the coupling of the mono- and bi-layer MoS\({}_{2}\) emission with a BSW. The MoS\({}_{2}\) transition dipole moment is oriented in the plane of the device [37], allowing for a perfect matching with a TE-polarized BSW mode. Through the coupling with this high Q surface mode, the MoS\({}_{2}\) emission can in-plane propagate covering long distances, towards the on-chip control of the TMDC optical signals. The second part reviews the experimental results on the strong-coupling between Frenkel exciton transitions and Bloch surface waves (i.e., BSWP), starting from the demonstration of the polariton generation to their long-range propagation and non-linear properties.