Condensed Matter

2512 Submissions

[3] viXra:2512.0067 [pdf] submitted on 2025-12-16 00:37:40

Magnetism And_superconductivity in Hydrogenated Graphite Foils (Short Version)

Authors: Nadina Gheorghiu, Charles R. Ebbing, Timothy J. Haugan
Comments: 5 Pages.

We have previously found magnetism and superconductivityin hydrogenated graphite [Gheorghiu, et al. (2020)].Herein, the two phenomena are observed in hydrogenated graphitefoils. As the strength of the magnetic field is increased, thetemperature-dependent magnetization shows several transitionsbetween different states: from Néel paramagnetic, to antiferromagnetic,to ferromagnetic superconductor, to high-temperaturesuperconductor with the critical temperature for the dominantphase Tc ∼ 50—60 K. The latter might be an orbital paramagneticglass ordering of π Josephson-coupled SC domains akinto a macroscopic quantization of the system. The magnetizationloops show the kink feature characteristic to granular SC. Theferromagnetism is observed up to room temperature. Thus, weobserve both magnetism and superconductivity in hydrogenatedgraphite foils.
Category: Condensed Matter

[2] viXra:2512.0059 [pdf] submitted on 2025-12-13 00:27:14

Fibonacci Sequence of Twist Angles in Superconducting Multi-Layer Graphene and Hydrogenated Graphitic Fibers

Authors: Nadina Gheorghiu, Charles R. Ebbing, George Y. Panasyuk, Timothy J. Haugan
Comments: 8 Pages. To be published in IOP Conference Series, Materials Science and Engineering, ICMC 2025

A range of twist angles between adjacent surfaces/volumes are intrinsic to natural graphite or artificially design in multi-layer graphene. In addition, stacking faults can be created by the application of mechanic, electric or magnetic fields. Charge and spin transport then occur in relation to the existing twist-angle pattern. In two dimensions, a saddle point in the electronic band structure leads to divergence in the density of states, known as van Hove singularities (vHs). The energy difference between vHs for the conduction and valence bands was found to increase with the twist angle  between neighboring graphite domains with respect to the c axis (perpendicular to the graphite planes). In this work, we estimate  for the superconducting (SC)-like nano-size multi-layer granular domain in hydrogenated graphitic fibers [1]. We show that this value for  and the values found by others for few-layer graphene might actually form the Fibonacci mathematical sequence. Moreover, SC hydrogenated graphite can harbour higher-order topology as reflected in at least quadratic energy gap flattening. Charge transport and magnetization measurements on hydrogenated graphitic fibers have been done using a Quantum Design Physical Properties Measurement System.
Category: Condensed Matter

[1] viXra:2512.0003 [pdf] submitted on 2025-12-02 02:30:00

Room-Temperature Superconductor (300 K and 0 Gpa)

Authors: Giustino Travaglini
Comments: 3 Pages. (Note by viXra Admin: Please submit article written with AI assistance to ai.viXra.org)

The realization of room-temperature superconductivity at ambient pressure remains the ultimate goal of condensed matter physics. While high-pressure superhydrides (e.g., ������10) have achieved high critical temperatures (Tc), they lose stability upon decompression. Here, I predict a novel ternary clathrate structure, ����2 ���� ��2��18, designed to maintain high-Tc superconductivity at 0GPa via a "kinetic locking" mechanism. First-principles calculations reveal that a rigid Boron-Magnesium host lattice can chemically confine dense hydrogen clusters, mimicking the effects of external pressure. I estimate a Tc of ~298 K driven by strong electron-phonon coupling (��≈2.6). Furthermore, I propose a cry
Category: Condensed Matter