scholarly journals Electron–phonon coupling in engineered magnetic molecules

2016 ◽  
Vol 52 (76) ◽  
pp. 11359-11362 ◽  
Author(s):  
Violeta Iancu ◽  
Koen Schouteden ◽  
Zhe Li ◽  
Chris Van Haesendonck

We probe electron–phonon coupling in CoTPyP and CrTPyP synthesized magnetic molecules. Low temperatures STS reveals pronounced Kondo resonances at zero bias in both molecules and additional Kondo resonance replicas observed at higher voltages in vibrating CoTPyP molecules.

1992 ◽  
Vol 270 ◽  
Author(s):  
Kosmas Prassides ◽  
Christos Christides ◽  
John Tomkinson ◽  
Matthew J. Rosseinsky ◽  
D. W. Murphy ◽  
...  

ABSTRACTThe phonon spectra of pristine fullerene, superconducting K3C60 and saturation-doped Rb6C60 measured by inelastic neutron scatteringin the energy range 2.5 - 200 meV at low temperatures reveal substantial broadening of five-fold degenerate Hg intramolecular vibrational modes both in the low-energy radial and the high-energy tangential part of the spectrum. This provides strong evidence for a traditional phonon-mediated mechanism of superconductivity in the fullerides but with an electron-phonon coupling strength distributed over a wide range of energies (33-195 meV) as a result of the finite curvature of the fullerene spherical cage.


1988 ◽  
Vol 02 (05) ◽  
pp. 975-980 ◽  
Author(s):  
I. Morgenstern

Monte Carlo simulations based on the Trotter-Suzuki transformation were carried out using 6 × 6 and 12 × 12 lattices and the single-band Hubbard model with intermediate-range repulsive interaction. The absence of the "minus-sign problem" for sufficiently low temperatures and appropriate doping indicates bosonic behavior reminiscent of superconductivity. It was found that holes prefer to pair on next-nearest-neighbor sites while nearest neighbors are suppressed. Additional electron-phonon coupling in the form of the breathing mode not only preserves this symmetry but strengthening of the bosonic background indicates the possibility of superconductivity.


2021 ◽  
Vol 12 (6) ◽  
pp. 1690-1695
Author(s):  
Zhongyu Liu ◽  
Yingwei Li ◽  
Wonyong Shin ◽  
Rongchao Jin

2021 ◽  
Vol 103 (2) ◽  
Author(s):  
I.Yu. Sklyadneva ◽  
R. Heid ◽  
P. M. Echenique ◽  
E. V. Chulkov

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Rui Su ◽  
Zhaojian Xu ◽  
Jiang Wu ◽  
Deying Luo ◽  
Qin Hu ◽  
...  

AbstractThe performance of perovskite photovoltaics is fundamentally impeded by the presence of undesirable defects that contribute to non-radiative losses within the devices. Although mitigating these losses has been extensively reported by numerous passivation strategies, a detailed understanding of loss origins within the devices remains elusive. Here, we demonstrate that the defect capturing probability estimated by the capture cross-section is decreased by varying the dielectric response, producing the dielectric screening effect in the perovskite. The resulting perovskites also show reduced surface recombination and a weaker electron-phonon coupling. All of these boost the power conversion efficiency to 22.3% for an inverted perovskite photovoltaic device with a high open-circuit voltage of 1.25 V and a low voltage deficit of 0.37 V (a bandgap ~1.62 eV). Our results provide not only an in-depth understanding of the carrier capture processes in perovskites, but also a promising pathway for realizing highly efficient devices via dielectric regulation.


2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Qing Dong ◽  
Quanjun Li ◽  
Shujia Li ◽  
Xuhan Shi ◽  
Shifeng Niu ◽  
...  

AbstractThe adoption of high pressure not only reinforces the comprehension of the structure and exotic electronic states of transition metal dichalcogenides (TMDs) but also promotes the discovery of intriguing phenomena. Here, 1T-TaS2 was investigated up to 100 GPa, and re-enhanced superconductivity was found with structural phase transitions. The discovered I4/mmm TaS2 presents strong electron–phonon coupling, revealing a good superconductivity of the nonlayered structure. The P–T phase diagram shows a dome shape centered at ~20 GPa, which is attributed to the distortion of the 1T structure. Accompanied by the transition to nonlayered structure above 44.5 GPa, the superconducting critical temperature shows an increasing trend and reaches ~7 K at the highest studied pressure, presenting superior superconductivity compared to the original layered structure. It is unexpected that the pressure-induced re-enhanced superconductivity was observed in TMDs, and the transition from a superconductor with complicated electron-pairing mechanism to a phonon-mediated superconductor would expand the field of pressure-modified superconductivity.


2021 ◽  
Vol 203 (1-2) ◽  
pp. 180-193
Author(s):  
S. Giaremis ◽  
Ph. Komninou ◽  
Th. Karakostas ◽  
J. Kioseoglou

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
M. Osiekowicz ◽  
D. Staszczuk ◽  
K. Olkowska-Pucko ◽  
Ł. Kipczak ◽  
M. Grzeszczyk ◽  
...  

AbstractThe temperature effect on the Raman scattering efficiency is investigated in $$\varepsilon$$ ε -GaSe and $$\gamma$$ γ -InSe crystals. We found that varying the temperature over a broad range from 5 to 350 K permits to achieve both the resonant conditions and the antiresonance behaviour in Raman scattering of the studied materials. The resonant conditions of Raman scattering are observed at about 270 K under the 1.96 eV excitation for GaSe due to the energy proximity of the optical band gap. In the case of InSe, the resonant Raman spectra are apparent at about 50 and 270 K under correspondingly the 2.41 eV and 2.54 eV excitations as a result of the energy proximity of the so-called B transition. Interestingly, the observed resonances for both materials are followed by an antiresonance behaviour noticeable at higher temperatures than the detected resonances. The significant variations of phonon-modes intensities can be explained in terms of electron-phonon coupling and quantum interference of contributions from different points of the Brillouin zone.


2020 ◽  
Vol 2 (2) ◽  
Author(s):  
Adrian Ruckhofer ◽  
Davide Campi ◽  
Martin Bremholm ◽  
Philip Hofmann ◽  
Giorgio Benedek ◽  
...  

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