Condensed Matter

2308 Submissions

[3] viXra:2308.0133 [pdf] submitted on 2023-08-22 03:39:47

The First Room-Temperature Ambient-Pressure Superconductor

Authors: Sukbae Lee, Ji-Hoon Kim, Young-Wan Kwon
Comments: 22 Pages.

For the first time in the world, we succeeded in synthesizing the room-temperature superconductor (Tc≥400 K, 127∘C) working at ambient pressure with a modified lead-apatite (LK-99) structure. The superconductivity of LK-99 is proved with the Critical temperature (Tc), Zero-resistivity, Critical current (Ic), Critical magnetic field (Hc), and the Meissner effect. The superconductivity of LK-99 originates from minute structural distortion by a slight volume shrinkage (0.48 %), not by external factors such as temperature and pressure. The shrinkage is caused by Cu2+ substitution of Pb2+(2) ions in the insulating network of Pb(2)-phosphate and it generates the stress. It concurrently transfers to Pb(1) of the cylindrical column resulting in distortion of the cylindrical column interface, which creates superconducting quantum wells (SQWs) in the interface. The heat capacity results indicated that the new model is suitable for explaining the superconductivity of LK-99. The unique structure of LK-99 that allows the minute distorted structure to be maintained in the interfaces is the most important factor that LK-99 maintains and exhibits superconductivity at room temperatures and ambient pressure.
Category: Condensed Matter

[2] viXra:2308.0107 [pdf] submitted on 2023-08-16 20:20:18

On the Microscopic Substantiation of Two-Fluid Hydrodynamics in Helium II

Authors: S. V. Akimenko
Comments: 7 Pages.

It is shown that the formally correct expression of the existing theory of superfluidity, obtained for the momentum of a phonon gas in helium II, does not describe the physically real transfer of the effective mass of the phonon gas. The physically real transferable effective mass of a phonon gas turns out to be (10)^12 times less than it is considered in the existing theory. It is established that the laws of energy and momentum transformation of a massive quasiparticle in helium II differ somewhat from the corresponding laws used in the existing theory. It follows from this that if the gas of rotons with the dispersion law introduced in 1947 behaves as a whole, then it must be entirely at rest relative to the "unexcited background" in helium II. It is noted that the criterion for the superfluidity of liquid helium implicitly assumes the use of an additional hypothesis about the direction of the momentum excited in liquid helium II quasiparticle (phonon).
Category: Condensed Matter

[1] viXra:2308.0035 [pdf] submitted on 2023-08-07 23:35:32

Superconductors with Close Interatomic Distances Have High Superconducting Transition Temperatures

Authors: Kazuo Abe
Comments: 3 Pages.

The essence of electrical resistance is the scattering of free electrons by non-free electron orbital regions generated by lattice vibrations; therefore, superconductors with structures where non-free electron orbital regions are not generated due to close interatomic distances have higher superconducting transition temperatures.
Category: Condensed Matter