scholarly journals Unified phase diagram of Fe-based superconductors based on electron correlation strength

2018 ◽  
Vol 67 (20) ◽  
pp. 207405
Author(s):  
Xu Hai-Chao ◽  
Niu Xiao-Hai ◽  
Ye Zi-Rong ◽  
Feng Dong-Lai
Keyword(s):  
Phase Diagram ◽  
Electron Correlation ◽  
Correlation Strength

scholarly journals Importance of $${{d}}_{{{xy}}}$$ orbital and electron correlation in iron-based superconductors revealed by phase diagram for 1111-system

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tsuyoshi Kawashima ◽  
Shigeki Miyasaka ◽  
Hirokazu Tsuji ◽  
Takahiro Yamamoto ◽  
Masahiro Uekubo ◽  
...  
Keyword(s):  
Electron Correlation ◽  
Weak Coupling ◽  
Structural Parameters ◽  
Structural Flexibility ◽  
Superconducting Transition ◽  
Iron Based Superconductors ◽  
Wide Range ◽  
Band Filling ◽  
Iron Based ◽  
Correlation Strength

AbstractThe structural flexibility at three substitution sites in LaFeAsO enabled investigation of the relation between superconductivity and structural parameters over a wide range of crystal compositions. Substitutions of Nd for La, Sb or P for As, and F or H for O were performed. All these substitutions modify the local structural parameters, while the F/H-substitution also changes band filling. It was found that the superconducting transition temperature $$T_{\text{c}}$$ T c is strongly affected by the pnictogen height $$h_{Pn}$$ h Pn from the Fe-plane that controls the electron correlation strength and the size of the $$d_{xy}$$ d xy hole Fermi surface (FS). With increasing $$h_{Pn}$$ h Pn , weak coupling BCS superconductivity switches to the strong coupling non-BCS one where electron correlations and the $$d_{xy}$$ d xy hole FS may be important.

scholarly journals Metal-insulator Phase Diagram for the Fully Diagonal Disordered Hubbard Model at Half-filling

2016 ◽  
Vol 26 (2) ◽  
pp. 159
Author(s):  
Hoang Anh Tuan ◽  
Nguyen Thi Hai Yen
Keyword(s):  
Phase Diagram ◽  
Mean Field Theory ◽  
Mean Field ◽  
Metallic State ◽  
Strongly Correlated ◽  
Potential Approximation ◽  
Metal Insulator ◽  
Band Insulator ◽  
Half Filling ◽  
Correlation Strength

The electronic properties of strongly correlated systems with binary type of disorder are investigated using the coherent potential approximation. For half-filled system, two transitions from a band insulator via a metallic state to a Mott insulator are found with increasing the correlation strength of only one of the constituents. Our phase diagram is consistent with those obtained by the dynamical mean field theory.

scholarly journals Electronic phase diagram of Fe1+yTe1−xSex revealed by magnetotransport measurements

2020 ◽  
Vol 34 (19n20) ◽  
pp. 2040051
Author(s):  
T. Watanabe ◽  
T. Otsuka ◽  
S. Hagisawa ◽  
Y. Koshika ◽  
S. Adachi ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Phase Diagram ◽  
Single Crystals ◽  
Electron Correlation ◽  
The Third ◽  
Electronic Phase ◽  
Electronic Phase Diagram ◽  
Excess Fe ◽  
Annealing Method ◽  
Correlation Level

Among the Fe-based superconductors, [Formula: see text] is unique in that its crystal structure is the simplest and the electron correlation level is the strongest, and thus it is important to investigate the doping [Formula: see text]-temperature [Formula: see text] phase diagram of this system. However, inevitably incorporated excess Fe currently prevents the establishment of the true phase diagram. We overcome the aforementioned significant problem via developing a new annealing method termed as “Te-annealing” wherein single crystals are annealed under Te vapor. Specifically, we conducted various magnetotransport measurements on Te-annealed superconducting [Formula: see text]. We observed that crossover from the incoherent to the coherent electronic state and opening of the pseudogap occurs at high temperatures ([Formula: see text]150 K for [Formula: see text]). This is accompanied by a more substantial pseudogap and the emergence of a phase with a multi-band nature at lower temperatures (below [Formula: see text] for [Formula: see text]) before superconductivity sets in. Based on the results, the third type electronic phase diagram in Fe-based high-[Formula: see text] superconductors is revealed.

scholarly journals Dependence of electron correlation strength inFe1+yTe1−xSexon Se content

2015 ◽  
Vol 92 (3) ◽  
Author(s):  
L. C. C. Ambolode ◽  
K. Okazaki ◽  
M. Horio ◽  
H. Suzuki ◽  
L. Liu ◽  
...  
Keyword(s):  
Electron Correlation ◽  
Correlation Strength

To What Extent are Inelastically Scattered Electrons Useful in the Stem?

1973 ◽  
Vol 31 ◽  
pp. 286-287 ◽  
Author(s):  
H. Rose
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Electron Correlation ◽  
Quantum Noise ◽  
Collection Efficiency ◽  
Scanning Transmission Electron Microscope ◽  
Electron Cloud ◽  
Scanning Time ◽  
Transmission Electron ◽  
Scanning Transmission

The scanning transmission electron microscope offers the possibility of utilizing inelastically scattered electrons. Use of these electrons in addition to the elastically scattered electrons should reduce the scanning time (dose) Which is necessary to keep the quantum noise below a certain level. Hence it should lower the radiation damage. For high resolution, Where the collection efficiency of elastically scattered electrons is small, the use of Inelastically scattered electrons should become more and more favorable because they can all be detected by means of a spectrometer. Unfortunately, the Inelastic scattering Is a non-localized interaction due to the electron-electron correlation, occurring predominantly at the circumference of the atomic electron cloud.

New developments in the ab initio determination of transition metal alloys phase diagram

1993 ◽  
Vol 90 ◽  
pp. 249-254 ◽  
Author(s):  
C Wolverton ◽  
M Asta ◽  
S Ouannasser ◽  
H Dreyssé ◽  
D de Fontaine
Keyword(s):  
Phase Diagram ◽  
Transition Metal ◽  
Ab Initio ◽  
Metal Alloys ◽  
New Developments ◽  
Transition Metal Alloys
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