Raman scattering from spin fluctuations inPr2−xCe

Abstract

Antiferromagnetic excitations in single crystals of Pr2 Ce Cu04~, Nd, "Ce"Cu04~, and Sm2 Ce Cu04~were investigated as a function of Ce concentration using Raman scattering at room temperature.The introduction of electrons by Ce doping significantly broadens the twomagnon peak in the B&g mode, indicating that zone-boundary magnons become damped with increasing Ce concentration. The existence of broad spin-pair-excitation spectra in the B,~and B2g modes at x =0.15 suggests that the short-range spin fluctuations persist in these electron-doped superconductors. The energy of the spin-pair-excitation peak in Pr~"Ce Cu04~is not affected by doping up to x=0.2. This is similar in behavior to the Sm& "Ce Cu04~system up to x=0.17.The absence of softening of the short-wavelength magnons in these systems is in marked contrast to the magnon softening behavior in La2 "Sr"Cu04~. The Raman spectra in Pr2 Ce Cu04 make no distinction between the superconducting and the metallic regions. The highly damped magnetic-excitation spectra support the picture that the spin-spin correlation length in the present systems decreases gradually with increasing Ce concentration.

Superconducting pairing and the pseudogap in the nematic dynamical stripe phase of La2−xSrxCuO4

“…4(b) 82 . However, the softening of the twomagnon peak is not observed in electron-doped cuprate superconductors [198][199][200][201] . The two-magnon peak energy does not shift in the insulating phase of NCCO, even if carriers are doped 201 .…”

Band Diagram and Rate Analysis of Thin Film Spinel LiMn2O4 Formed by Electrochemical Conversion of ALD‐Grown MnO

“…For these calculations, the HSE06 with 25% exact exchange was used, which had been shown to accurately describe the electronic structure of various crystalline phases of MnO 2 [24,53] and to accurately predict defect levels. [54] In order to model the electronic structure in a manner consistent with experimental operating temperatures and with the experimental observation of a Néel temperature well below 100 K for spinel LiMn 2 O 4 , [55] a constraint of low total spin was imposed by restricting calculations to spin configurations with low net spin. See Section 1 in the Supporting Information for further details of these calculations.…”

Raman Studies of Anisotropic Magnetic Excitations in Fluctuating Nematic Striped La2−x Sr x CuO4 and the Comparison to Uniform Nd2−x Ce x CuO4

“…High energy magnetic Raman scattering has been reported in hole doped superconductors [18,19,20,21,22,23,24] and electron-doped superconductors [25,26,27]. Many of them reported only the B 1g spectra, because the B 2g spectra are two-magnon scattering inactive.…”