Related papers: Why only hole conductors can be superconductors
Off-axis electron holography can measure the mean inner electric potential of materials. The theory of hole superconductivity predicts that when a material is cooled into the superconducting state it expels electrons from its interior to…
Momentum and energy conservation are fundamental tenets of physics, that valid physical theories have to satisfy. In the reversible transformation between superconducting and normal phases in the presence of a magnetic field, the mechanical…
Superconduction manifests when a steady-state current flows through a material without an electric field being present. It is argued here that the absence of scattering of the charge-carriers, although absolutely necessary, is not…
We present results on heavily underdoped Y_1-xCa_xBa_2Cu_3O_6+y which provide the evidence that the doping mechanism (cation substitution or oxygen loading) directly determines whether the corresponding injected mobile holes contribute to…
In a semiclassical view superconductivity is attributed exclusively to the advance of atoms' outer s electrons through the nuclei of neighbor atoms in a solid. The necessary progression of holes in the opposite direction has the electric…
Ted Geballe has contributed enormously to the knowledge of superconducting materials during an illustrious scientific career spanning seven decades, encompassing groundbreaking discoveries and studies of both so-called conventional and…
I discuss the process of magnetic field generation in rotating superconductors in simply connected and multiply connected geometries. In cooling a normal metal into the superconducting state while it is rotating, electrons slow down or…
It is argued that experiments on rotating superconductors provide evidence for the existence of macroscopic spin currents in superconductors in the absence of applied external fields. Furthermore it is shown that the model of hole…
On a microscopic scale, resistivity during electric conduction is caused by collisions of the free conduction electrons with the obstructing atoms or molecules of the conductor material, resulting in heat production. Based on this…
This paper presents a novel theory for understanding the mechanics behind non-conventional superconductors. It presents the hypothesis that non-conventional superconductors are 2D lattices of super-cells and that the superconductivity…
Since their experimental discovery in 1989, the electron-doped cuprate superconductors have presented both a major challenge and a major opportunity. The major challenge has been to determine whether these materials are fundamentally…
Superconductivity allows to construct and operate magnets at field values beyond 2 Tesla, the practical limitation of normal-conducting magnets exploiting ferro-magnetism. The field of superconducting magnets is dominated by the field…
A magnetic field H is expelled from the interior of a metal becoming superconducting. Everybody thinks the phenomenon is perfectly well understood, particularly scientists with the highest H-index think that. I don't. I will explain why I…
Indium-doped SnTe has been of interest because the system can exhibit both topological surface states and bulk superconductivity. While the enhancement of the superconducting transition temperature is established, the character of the…
From the very beginning K. Alex M\"uller emphasized that the materials he and George Bednorz discovered in 1986 were $hole$ superconductors. Here I would like to share with him and others what I believe to be $the$ key reason for why high…
The existing theory about the cuprate superconductor bases on band theory, almost all neglects the position difference of Cu-O ions on CuO2 plane, and assumes that the charge on ions are averagely distributed. Considering that the nature of…
To change the velocity of an electron requires that a Lorentz force acts on it, through an electric or a magnetic field. We point out that within the conventional understanding of superconductivity electrons appear to change their velocity…
A superconductor is a material that can conduct electricity with no resistance below its critical temperature (Tc). The highest Tc that has been achieved in cuprates1 is 133 K at ambient pressure2 and 164 K at high pressures3. As the nature…
By drilling periodic thru-holes in a suspended film, the phonon system can be modified. Being motivated by the BCS theory, the technique, so-called phonon engineering, was applied to a niobium sheet. The newly emergent high-$T_{c}$…
During the past few decades, several new classes of superconductors have been discovered. Most of these do not appear to be related to traditional superconductors. As a consequence, it is felt by many that for these materials,…