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The decay dynamics of the α-group ( 2D →4S transition) of N atoms stabilized in the collection of N2–Ne nanoclusters were studied at a temperature of 1.3 K. The variation of the N2/Ne ratio in nanoclusters results in substantial changes in the luminescence spectra of the α-group and in the characteristic decay times for the components of these spectra. In all obtained α-group spectra, the narrow component at λ = 519.9 nm was observed. The spectroscopic results provide information about the structure of the nitrogen–neon nanoclusters. At elevated temperatures ( ≈ 15–36 K), enhanced oxygen β-group luminescence is observed in N2–Ne nanoclusters, with a smaller intensity enhancement than those observed within pure N2 and mixed N2–Kr nanoclusters. These results confirm the energy transfer mechanism, in which excited nitrogen molecules formed on the nanocluster surface transfer energy to the stabilized oxygen atoms through the chain of N2 molecules in a solid matrix. 

ABSTRACT Coupling superconductors to quantum Hall edge states is the subject of intense investigation as part of the ongoing search for non-abelian excitations. Our group has previously observed supercurrents of hundreds of picoamperes in graphene Josephson junctions in the quantum Hall regime. One of the explanations of this phenomenon involves the coupling of an electron edge state on one side of the junction to a hole edge state on the opposite side. In our previous samples, these states are separated by several microns. Here, a narrow trench perpendicular to the contacts creates counterpropagating quantum Hall edge channels tens of nanometres from each other. Transport measurements demonstrate a change in the low-field Fraunhofer interference pattern for trench devices and show a supercurrent in both trench and reference junctions in the quantum Hall regime. The trench junctions show no enhancement of quantum Hall supercurrent and an unexpected supercurrent periodicity with applied field, suggesting the need for further optimization of device parameters.