Submit to Condensed Matter Review for Condensed Matter

Journal Menu

Journal Browser

Condens. Matter, Volume 9, Issue 3 (September 2024) – 6 articles

Cover Story (view full-size image): Cleaving highly oriented pyrolytic graphite with scotch tape produces nearly parallel line defects on the surface. Strain fluctuations, felt by electrons as effective gauge fields, localize and pair electrons on granules along the line defects, where they Bose condense, forming an emergent Josephson junction array in its bosonic topological insulator state. Cooper pairs tunnel without dissipation on the line defects, forming the edges of this topological insulator, when vortices are pinned by the extremely high conductivity of the graphene sheets, so that no quantum phase slips can occur. Electrons remain paired up to room temperature due to the tiny lateral dimension of the defects while vortices remain pinned up to room temperature due to their embedding in a 3D structure. View this paper

Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
You may sign up for e-mail alerts to receive table of contents of newly released issues.
PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.

Order results

Result details

Section

Show export options Show export options

Select all

Export citation of selected articles as:

9 pages, 1098 KiB

Open AccessFeature PaperArticle

Room-Temperature Superconductivity in 1D

by Carlo A. Trugenberger

Condens. Matter 2024, 9(3), 34; https://doi.org/10.3390/condmat9030034 - 8 Sep 2024

Viewed by 1277

Abstract

We review the theoretical model underpinning the recently reported room-temperature, ambient-pressure superconductivity along line defects on the surface of highly oriented pyrolytic graphite. The main ingredients for this 1D room-temperature superconductivity are pairing by effective strain gauge fields, the formation of an effective Josephson junction array in its Bose metal state on the surface and the suppression of phase slips by dimensional embedding in an extremely well-conducting 3D bulk structure. Full article

(This article belongs to the Special Issue Superstripes Physics, 3rd Edition)

► Show Figures

Figure 1

9 pages, 274 KiB

Open AccessArticle

Remarks on the Quantum Effects of Screw Dislocation Topology and Missing Magnetic Flux

by Knut Bakke

Condens. Matter 2024, 9(3), 33; https://doi.org/10.3390/condmat9030033 - 8 Aug 2024

Viewed by 851

Abstract

We revisit the interaction between a point charge and an inhomogeneous magnetic field that yields the magnetic quantum dot system. This magnetic field is defined by filling the whole space, except for a region of radius

r_{0}

. Then, we assume that [...] Read more.

r_{0}

. Then, we assume that there is an impenetrable potential wall located at

r_{0}

and discuss the quantum effects of screw dislocation topology and the missing magnetic flux. We first show that Landau levels can be achieved even though there is the presence of an impenetrable potential wall. We go further by discussing the confinement of a point charge to a cylindrical wire. In both cases, we show Aharonov–Bohm-type effects for bound states can be obtained from the influence of the screw dislocation topology and the missing magnetic flux. Later, we discuss the influence of the screw dislocation topology and the missing magnetic flux on the magnetization and the persistent currents. Full article

(This article belongs to the Section Condensed Matter Theory)

12 pages, 871 KiB

Open AccessArticle

Atomristor Mott Theory of Sn Adatom Adlayer on a Si Surface

by Luis Craco, Edson F. Chagas, Sabrina S. Carara and Byron Freelon

Condens. Matter 2024, 9(3), 32; https://doi.org/10.3390/condmat9030032 - 2 Aug 2024

Viewed by 1194

Abstract

We use a combination of density functional theory (DFT) and dynamical mean field theory (DMFT) to unveil orbital field-induced electronic structure reconstruction of the atomic Sn layer deposited onto a Si(111) surface (Sn/Si(111)−

\sqrt{3} \times \sqrt{3} R 30^{\circ}

), also referred to [...] Read more.

\sqrt{3} \times \sqrt{3} R 30^{\circ}

), also referred to as

α

-Sn. Our DFT + DMFT results indicate that

α

-Sn is an ideal testing ground to explore electric field-driven orbital selectivity and Mott memory behavior, all arising from the close proximity of

α

-Sn to metal insulator transitions. We discuss the relevance of orbital phase changes for

α

-Sn in the context of the current–voltage (

I - V

) characteristic for future silicon-based metal semiconductor atomristors. Full article

(This article belongs to the Section Condensed Matter Theory)

► Show Figures

Figure 1

13 pages, 5141 KiB

Open AccessArticle

Enhancing the Photoelectrochemical Performance of a Superlattice p–n Heterojunction CuFe₂O₄/ZnFe₂O₄ Electrode for Hydrogen Production

by M. K. Al Turkestani

Condens. Matter 2024, 9(3), 31; https://doi.org/10.3390/condmat9030031 - 26 Jul 2024

Viewed by 698

Abstract

A p–n heterojunction film consisting of p-type CuFe₂O₄ and n-type ZnFe₂O₄ was fabricated in this study. The n-type ZnFe₂O₄ film was deposited on a stainless steel substrate using the spray pyrolysis method, after which a top layer of p-type CuFe₂O₄ thin film was deposited and annealed. Characterization techniques, such as X-ray diffraction, scanning electron microscopy, UV–Vis diffuse reflectance spectroscopy, and photoluminescence, confirmed the formation of a superlattice p–n heterojunction between CuFe₂O₄ and ZnFe₂O₄. Photoelectrochemical measurements were conducted to investigate the photoelectrochemical properties of the samples, resulting in a photocurrent of 1.2 mA/cm² at 1.5 V (vs. Ag/AgCl) under illumination from a 100-watt LED light source. Utilizing the p–n junction of CuFe₂O₄/ZnFe₂O₄ as a photoanode increased the hydrogen production rate by 30% compared to that of the dark measurement. This enhancement in performance was attributed to the potential barrier at the p–n heterojunction interface, which improved the separation of photoinduced electron–hole pairs and facilitated a more efficient charge transfer. Additionally, coating the stainless steel electrode with this ferrite sample improved both the corrosion resistance and the stability of hydrogen production over extended operation times. Full article

(This article belongs to the Section Physics of Materials)

► Show Figures

Figure 1

11 pages, 3470 KiB

Open AccessArticle

The EuAPS Betatron Radiation Source: Status Update and Photon Science Perspectives

by Federico Galdenzi, Maria Pia Anania, Antonella Balerna, Richard J. Bean, Angelo Biagioni, Claudio Bortolin, Luca Brombal, Francesco Brun, Marcello Coreno, Gemma Costa, Lucio Crincoli, Alessandro Curcio, Martina Del Giorno, Enrico Di Pasquale, Gianluca di Raddo, Valentina Dompè, Sandro Donato, Zeinab Ebrahimpour, Antonio Falone, Andrea Frazzitta, Mario Galletti, Andrea Ghigo, Stefano Lauciani, Andrea Liedl, Valerio Lollo, Augusto Marcelli, Emiliano Principi, Andrea R. Rossi, Federica Stocchi, Fabio Villa, Marco Zottola, Alessandro Cianchi, Francesco Stellato and Massimo Ferrario Show full author list Hide full author list

Condens. Matter 2024, 9(3), 30; https://doi.org/10.3390/condmat9030030 - 22 Jul 2024

Viewed by 962

Abstract

The EuPRAXIA EU project is at the forefront of advancing particle accelerator research and the development of photon sources through innovative plasma acceleration approaches. Within this framework, the EuAPS project aims to exploit laser wakefield acceleration to build and operate a betatron radiation source at the INFN Frascati National Laboratory. The EuAPS source will provide femtosecond X-ray pulses in the spectral region between about 1 and 10 keV, unlocking a realm of experimental ultrafast methodologies encompassing diverse imaging and X-ray spectroscopy techniques. This paper presents a description of the EuAPS betatron source, including simulations of the photon beam parameters, outlines the preliminary design of the dedicated photon beamline, and provides an insightful overview of its photon science applications. Full article

(This article belongs to the Section Spectroscopy and Imaging in Condensed Matter)

► Show Figures

Figure 1

28 pages, 13451 KiB

Open AccessFeature PaperArticle

The Nature of Pointer States and Their Role in Macroscopic Quantum Coherence

by Philip Turner and Laurent Nottale

Condens. Matter 2024, 9(3), 29; https://doi.org/10.3390/condmat9030029 - 17 Jul 2024

Viewed by 912

Abstract

This article begins with an interdisciplinary review of a hydrodynamic approach to understanding the origins and nature of macroscopic quantum phenomena in high-temperature superconductivity, superfluidity, turbulence and biological systems. Building on this review, we consider new theoretical insights into the origin and nature of pointer states and their role in the emergence of quantum systems. The approach includes a theory of quantum coherence underpinned by turbulence, generated by a field of pointer states, which take the form of recirculating, spin-1/2 vortices (toroids), interconnected via a cascade of spin-1 vortices. Decoherence occurs when the bosonic network connecting pointer states is disrupted, leading to their localisation. Building further on this work, we explore how quantum particles (in the form of different vortex structures) could emerge as the product of a causal dynamic process, within a turbulent (fractal) spacetime. The resulting particle structures offer new insights into intrinsic spin, the probabilistic nature of the wave function and how we might consider pointer states within the standard “point source” representation of a quantum particle, which intuitively requires a more complexed description. Full article

(This article belongs to the Special Issue Feature Papers from Condensed Matter Editorial Board Members)

► Show Figures