AI Article Synopsis
- In conventional superconductors like magnesium diboride (MgB), superconductivity primarily arises from electron-phonon coupling, particularly through boron-boron bond vibrations.
- The study explores how interfaces, specifically between MgB films and SiC substrates, may affect this electron-phonon coupling, which has not been widely investigated.
- Using advanced techniques like electron microscopy and spectroscopy, researchers found a thin MgO layer at the interface that enhances electron-phonon coupling, suggesting that engineering these interfaces can improve superconductivity.
Article Abstract
In conventional Bardeen-Cooper-Schrieffer (BCS) superconductors, electron-phonon coupling is the fundamental mechanism of superconductivity. For instance, the superconductivity of magnesium diboride (MgB) comes from the coupling between modes (in-plane boron-boron bond vibrations) and self-doped charge carriers. In thin films and ceramics of BCS superconductors, interfaces with discontinuous chemical bonds may alter the local electron-phonon coupling. However, such effects remain largely unexplored. Here, we investigate the heterointerface of the MgB film on the SiC substrate at the atomic scale using electron microscopy and spectroscopy. We detect the presence of a thin MgO layer with a thickness of ∼1 nm between MgB and SiC. Atomic-level electron energy loss spectra (EELS) show MgB- mode splitting and softening near the MgB/MgO interface, which enhances electron-phonon coupling at the interface. Our findings highlight the potential of interface engineering to enhance superconductivity via modulating local phonon states and/or electron states.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/acs.nanolett.4c03170 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
On-chip cryogenic low-pass filters based on finite ground-plane coplanar waveguides for quantum measurements.
Rev Sci Instrum
January 2025
Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala 695551, India.
Quantum technology exploits fragile quantum electronic phenomena whose energy scales demand ultra-low electron temperature operation. The lack of electron-phonon coupling at cryogenic temperatures makes cooling the electrons down to a few tens of millikelvin a non-trivial task, requiring extensive efforts on thermalization and filtering high-frequency noise. Existing techniques employ bulky and heavy cryogenic metal-powder filters, which prove ineffective at sub-GHz frequency regimes and unsuitable for high-density quantum circuits such as spin qubits.
View Article and Find Full Text PDFEnhanced two-temperature model and its application in comprehensive analysis of femtosecond laser melting of gold, copper and their alloys.
Phys Chem Chem Phys
January 2025
Theoretical Physics Section, Bhabha Atomic Research Centre, Mumbai-400085, India.
Extensive research on ultrashort laser-induced melting of noble metals like Au, Ag and Cu is available. However, studies on laser energy deposition and thermal damage of their alloys, which are currently attracting interest for energy harvesting and storage devices, are limited. This study investigates the melting damage threshold (DT) of three intermetallic alloys of Au and Cu (AuCu, AuCu and AuCu) subjected to single-pulse femtosecond laser irradiation, comparing them with their constituent metals.
View Article and Find Full Text PDFThermoelectric Properties of a Light Compound FeS: the Role of Electron Correlation Strengthened Spin-Orbital Coupling.
Small
January 2025
Center of Quantum Materials and Devices, College of Physics, Chongqing University, Chongqing, 401331, China.
Spin-orbit coupling (SOC) induced nontrivial bandgap and complex Fermi surface has been considered to be profitable for thermoelectrics, which, however, is generally appreciable only in heavy elements, thereby detrimental to practical application. In this study, the SOC-driven extraordinary thermoelectric performance in a light 2D material Fe₂S₂ is demonstrated via first-principles calculations. The abnormally strong SOC, induced by electron correlation through 3d orbitals polarization, significantly renormalizes the band structures, which opens the bandgap via Fe 3d orbitals inversion, exposes the second conduction valley with weak electron-phonon coupling, and aligns the energy of Fe 3d and S 3p orbitals with divergent momentum in valence band.
View Article and Find Full Text PDFDecoupling Carrier Dynamics and Energy Transport in Ultrafast Near-Field Nanoscopy.
Nano Lett
January 2025
Laser Thermal Laboratory, Department of Mechanical Engineering, University of California, Berkeley, California 94720, United States.
Ultrafast near-field optical nanoscopy has emerged as a powerful platform to characterize low-dimensional materials. While analytical and numerical models have been established to account for photoexcited carrier dynamics, quantitative evaluation of the associated pulsed laser heating remains elusive. Here, we decouple the photocarrier density and temperature increase in near-field nanoscopy by integrating the two-temperature model (TTM) with finite-difference time-domain (FDTD) simulations.
View Article and Find Full Text PDFElectron-phonon coupling and thermal transport properties of GaN/AlGaN heterojunction under strain regulation.
Phys Chem Chem Phys
January 2025
Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences, Suzhou 215123, China.
In the study of GaN/AlGaN heterostructure thermal transport, the interference of strain on carriers cannot be ignored. Although existing research has mainly focused on the intrinsic electronic and phonon behavior of the materials, there is a lack of studies on the transport characteristics of the electron-phonon coupling in heterostructures under strain control. This research comprehensively applies first-principles calculations and the Boltzmann transport equation simulation method to deeply analyze the thermal transport mechanism of the GaN/AlGaN heterojunction considering in-plane strain, with particular attention to the regulatory role of electron-phonon coupling on thermal transport.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!