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We theoretically investigate a topological Kitaev chain connected to a double quantum-dot (QD) setup hybridized with metallic leads. In this system, we observe the emergence of two striking phenomena: i) a decrypted Majorana Fermion (MF)-qubit recorded over a single QD, which is detectable by means of conductance measurements due to the asymmetrical MF-leaked state into the QDs; ii) an encrypted qubit recorded in both QDs when the leakage is symmetrical. In such a regime, we have a cryptographylike manifestation, since the MF-qubit becomes bound states in the continuum, which is not detectable in conductance experiments. PACS numbers: 72.10.Fk 73.63.Kv 74.20.MnIntroduction.-It is well known that Majorana fermions (MFs) zero-modes [1,2] are expected to appear bounded to the edges of a topological Kitaev chain [3][4][5][6][7]. Interestingly enough, by approaching the Kitaev chain to a quantum dot (QD), the MF state leaks[8] into it and manifests itself as a zero-bias peak (ZBP) in conductance measurements. The latter reveals experimentally the MF-qubit recorded over the QD. Indeed, such a phenomenon was experimentally confirmed in a QD hybridnanowire made by InAs/Al[9] with huge spin-orbit interaction and magnetic fields, being the nanowire placed close to an s-wave superconductor. It is worth mentioning that MFs can also emerge in the fractional quantum Hall state with filling-factor ν = 5/2[10], in threedimensional topological insulators [11], at the core of superconducting vortices [12][13][14] and on the edges of ferromagnetic atomic chains covering superconductors with pronounced spin-orbit interaction [15,16], similarly to semiconducting nanowires [17]. In terms of technological applications, MFs-qubits are of particular interest. This is because of their topological protection against decoherence[3], a key ingredient for the achievement of efficient quantum computers.In this work, we show that the employment of two QDs, as depicted in Fig.1(a), enables the cryptography of the MF-qubit state η ↑ = 1

The structural properties of insulating α-NaYF 4 (cubic) nanoparticles with size ranging within 4 -25 nm were investigated by high-resolution 23 Na and 19 F solid-state Nuclear Magnetic Resonance (NMR) spectroscopy under magic angle spinning (MAS) with single pulse (SP-MAS), spin-echo (SE-MAS), inversion recovery, and 3Q-MAS

The Grüneisen ratio (Γ), i.e. the ratio of the linear thermal expansivity to the specific heat at constant pressure, quantifies the degree of anharmonicity of the potential governing the physical properties of a system. While Γ has been intensively explored in solid state physics, very little is known about its behavior for gases. This is most likely due to the difficulties posed to carry out both thermal expansion and specific heat measurements in gases with high accuracy as a function of pressure and temperature. Furthermore, to the best of our knowledge a comprehensive discussion about the peculiarities of the Grüneisen ratio is still lacking in the literature. Here we report on a detailed and comprehensive overview of the Grüneisen ratio. Particular emphasis is placed on the analysis of Γ for gases. The main findings of this work are: i) for the Van der Waals gas Γ depends only on the co-volume b due to interaction effects, it is smaller than that for the ideal gas (Γ = 2/3) and diverges upon approaching the critical volume; ii) for the Bose-Einstein condensation of an ideal boson gas, assuming the transition as first-order Γ diverges upon approaching a critical volume, similarly to the Van der Waals gas; iii) for 4 He at the superfluid transition Γ shows a singular behavior. Our results reveal that Γ can be used as an appropriate experimental tool to explore pressure-induced critical points.