Two-dimensional Superconductivity from Dimerization of Atomically Ordered AuTe2Se4/3 Cubes

The emergent phenomena such as superconductivity and topological phase transitions can be observed in strict two-dimensional crystalline matters. Artificial interfaces and one atomic thickness layers are typical 2D materials of this kind. Although having 2D characters, most bulky layered compounds, however, do not possess these striking properties. Here, we report the 2D superconductivity in bulky AuTe2Se4/3,where the reduction in dimensionality is achieved through inducing the elongated covalent Te-Te bonds. The atomic-resolution images reveal that the Au, Te and Se are atomically ordered in a cube, among which are Te-Te bonds of 3.18 A and 3.28 A. The superconductivity at 2.85 K is discovered, which is unraveled to be the quasi-2D nature owing to the BKT topological transition. The nesting of nearly parallel Fermi sheets could give rise to strong electron-phonon coupling. It is proposed to further depleting the thickness could result in more topologically-related phenomena.Comment: 16 pages, 5 figures,To be published in Nature Communication

Cell-specific detection of miR-375 downregulation for predicting the prognosis of esophageal squamous cell carcinoma by miRNA in situ hybridization

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Stability of linear and non-linear lambda and tripod systems in the presence of amplitude damping

We present the stability analysis of the dark states in the adiabatic passage for the linear and non-linear lambda and tripod systems in the presence of amplitude damping (losses). We perform an analytic evaluation of the real parts of eigenvalues of the corresponding Jacobians, the non-zero eigenvalues of which are found from the quadratic characteristic equations, as well as by the corresponding numerical simulations. For non-linear systems, we evaluate the Jacobians at the dark states. Similarly to the linear systems, here we also find the non-zero eigenvalues from the characteristic quadratic equations. We reveal a common property of all the considered systems showing that the evolution of the real parts of eigenvalues can be split into three stages. In each of them the evolution of the stimulated Raman adiabatic passage (STIRAP) is characterized by different effective dimension. This results in a possible adiabatic reduction of one or two degrees of freedom.Comment: 30 pages, 12 figure

Vacancy-tuned paramagnetic/ferromagnetic martensitic transformation in Mn-poor Mn_{1-x}CoGe alloys

It is shown that a temperature window between the Curie temperatures of martensite and austenite phases around the room temperature can be obtained by a vacancy-tuning strategy in Mn-poor Mn1-xCoGe alloys (0 <= x <= 0.050). Based on this, a martensitic transformation from paramagnetic austenite to ferromagnetic martensite with a large magnetization difference can be realized in this window. This gives rise to a magnetic-field-induced martensitic transformation and a large magnetocaloric effect in the Mn1-xCoGe system. The decrease of the transformation temperature and of the thermal hysteresis of the transformation, as well as the stable Curie temperatures of martensite and austenite, are discussed on the basis of the Mn-poor Co-vacancy structure and the corresponding valence-electron concentration.Comment: Manuscript revised. 18 pages, 6 figures and 1 table. Submitted for publication