scholarly journals Noncollinear magnetic ordering in a frustrated magnet: Metallic regime and the role of frustration

2017 ◽  
Vol 96 (22) ◽  
Author(s):  
Munir Shahzad ◽  
Pinaki Sengupta
Keyword(s):  
Magnetic Ordering ◽  
Frustrated Magnet

scholarly journals f-Electron and Magnetic Ordering Effects in Nickelates LaNiO2 and NdNiO2: Remarkable Role of The Cuprate-Like 3dx2-y2 Band

2020 ◽  
Author(s):  
Jianwei Sun ◽  
Ruiqi Zhang ◽  
Christopher Lane ◽  
Bahadur Singh ◽  
Johannes Nokelainen ◽  
...  
Keyword(s):  
Ground State ◽  
Exchange Coupling ◽  
Density Functional ◽  
High Temperature Superconductivity ◽  
Parent Compound ◽  
Magnetic Ordering ◽  
Striking Similarity ◽  
Infinite Layer ◽  
Open Questions

Abstract Recent discovery of superconductivity in the doped infinite-layer nickelates has renewed interest in understanding the nature of high-temperature superconductivity more generally. The low-energy electronic structure of the parent compound NdNiO2, the role of electronic correlations in driving superconductivity, and the possible relationship betweeen the cuprates and the nickelates are still open questions. Here, by comparing LaNiO2 and NdNiO2 systematically within a parameter free density functional framework, all-electron first-principles framework, we reveal the role Nd 4f-electrons in shaping the ground state of pristine NdNiO2. Strong similarities are found between the electronic structures of LaNiO2 and NdNiO2, except for the effects of the 4f-electrons. Hybridization between the Nd 4f and Ni 3d orbitals is shown to significantly modify the Fermi surfaces of various magnetic states. In contrast, the competition between the magnetically ordered phases depends mainly on the gaps in the Ni dx2-y2 band, so that the ground state in LaNiO2 and NdNiO2 turns out to be striking similarity to that of the cuprates. The d - p band-splitting is found to be much larger while the intralayer 3d ion-exchange coupling is smaller in the nickelates compared to the cuprates. Our estimated value of the on-site Hubbard U is similar to that in the cuprates, but the value of the Hund's coupling JH is found to be sensitive to the Nd magnetic moment. The exchange coupling J in NdNiO2 is only half as large as in the curpates, which may explain why Tc in the nickelates is half as large as the cuprates.

scholarly journals Magnetic ordering of itinerant systems: the role of kinetic interactions

2004 ◽  
Vol 344 (1-4) ◽  
pp. 231-242 ◽  
Author(s):  
Grzegorz Górski ◽  
Jerzy Mizia
Keyword(s):  
Magnetic Ordering

Unusual magnetic ordering transitions in nanoscale biphasic LuFeO3: the role of the ortho–hexa phase ratio and the local structure

2020 ◽  
Vol 8 (47) ◽  
pp. 17000-17008
Author(s):  
Smita Chaturvedi ◽  
Priyank Shyam ◽  
Mandar M. Shirolkar ◽  
Swathi Krishna S ◽  
Bhavesh Sinha ◽  
...  
Keyword(s):  
Local Structure ◽  
Magnetic Ordering ◽  
Phase Ratio ◽  
Significant Difference ◽  
Ordering Transitions

Significant difference in the nanoscale magnetism of nanoparticles and nanofibres of biphasic LuFeO3.

Dominant Role of a Pseudogap in the Physics of the Colossal Magnetoresistive Oxides

1998 ◽  
Vol 12 (29n31) ◽  
pp. 3389-3392 ◽  
Author(s):  
D. S. Dessau ◽  
T. Saitoh ◽  
C.-H. Park ◽  
Z.-X. Shen ◽  
Y. Moritomo ◽  
...  
Keyword(s):  
Dominant Role ◽  
Magnetic Ordering ◽  
High Energy ◽  
Spectral Weight ◽  
High Energy Resolution ◽  
Photoemission Spectroscopy ◽  
Colossal Magnetoresistive ◽  
Weight Density ◽  
Magnetic Ordering Temperature

We have performed direct electronic structure measurements of the colosssal magnetoresistive oxides using high energy resolution photoemission spectroscopy. A key result of these measurements is the discovery of a pseudogap which drastically supresses or completely removes the spectral weight (density of states) at the Fermi energy E F . It is shown that the pseudogap plays a dominant role in the "colossal" conductivity changes which occur across the magnetic ordering temperature. We briefly discuss possible origins for the pseudogap.

Sign in / Sign up

Export Citation Format

Share Document