Boron Nitride (BN) layers with sp2 bonding have been grown by Metal Organic Chemical Vapor Deposition (MOCVD) on AlN underlayers themselves deposited on c-plane sapphire substrates. Two different boron precursors were employed: trimethylboron (TMB) and triethylboron (TEB) while ammonia was used as the nitrogen precursor. The BN obtained epitaxial BN films contain ordered rhombohedral (rBN) and partially ordered turbostratic (tBN) stackings as evidenced by Xray Diffraction analysis. We discriminatively identify the PL signatures of the rBN and tBN from those typical of the hexagonal (hBN) and Bernal stackings (bBN). The optical signature of tBN appears at 5.45eV and it intercalates between the two recombination bands typical of rBN at 5.35 eV ( strong intensity) and 5.55 eV(weaker intensity) . The analogs of the high intensity band at 5.35 eV in rBN sit at 5.47 eV for hBN and at 5.54 eV for bBN.

Abstract Multi-orbital physics in quasi-two-dimensional electron gases (q2DEGs) triggers intriguing phenomena not observed in bulk materials, such as unconventional superconductivity and magnetism. Here, we investigate the mechanism of orbital selective switching of the spin-polarization in the oxide q2DEG formed at the (001) interface between the LaAlO 3 , EuTiO 3 and SrTiO 3 band insulators. By using density functional theory calculations, transport, magnetic and x-ray spectroscopy measurements, we find that the filling of titanium-bands with 3d xz /3d yz orbital character in the EuTiO 3 layer and at the interface with SrTiO 3 induces an antiferromagnetic to ferromagnetic switching of the exchange interaction between Eu-4f 7 magnetic moments. The results explain the observation of the carrier density-dependent ferromagnetic correlations and anomalous Hall effect in this q2DEG, and demonstrate how combined theoretical and experimental approaches can lead to a deeper understanding of emerging electronic phases and serve as a guide for the materials design of advanced electronic applications.

Both Classical and Quantum Electrodynamics predict the existence of dipole-dipole long-range electrodynamic intermolecular forces, however these have never been hitherto experimentally observed. The discovery of completely new and unanticipated forces acting between biomolecules could have considerable impact on our understanding of the dynamics and functioning of the molecular machines at work in living organisms. Here, using two independent approaches, we demonstrate experimentally for the first time the activation of resonant electrodynamic intermolecular forces. We characterize clustering transitions induced by these forces by fluorescence correlation spectroscopy when out-of-equilibrium conditions induce collective molecular oscillation observed by Terahertz (THz) spectroscopy. This is an unprecedented experimental \textit{proof of principle} of a physical phenomenon that, having been observed for bio-macromolecules and with a long-range of action (up to 1000 ${\mathring{A}}$), could be of importance for biology. Therefore, in addition to thermal fluctuations that drive molecular motion randomly, these resonant (and thus selective) electrodynamic forces may contribute to molecular encounters in the crowded cellular space. We anticipate our findings will provide a basis for future systematic deepening of physical aspects of the reported phenomena and for future systematic assessment of the relevance of electrodynamic forces in shaping the dynamics of biomolecular encounters and recognition in biology.