# Spin excitations in K$_{0.84}$Fe$_{1.99}$Se$_2$ superconductor as studied by M\

@inproceedings{Li2011SpinEI,
title={Spin excitations in K\$\_\{0.84\}\$Fe\$\_\{1.99\}\$Se\$\_2\$ superconductor as studied by M\},
author={Zhiwei Li and Xiaoming Ma and Hua Pang and Fashen Li},
year={2011}
}
M\"ossbauer spectroscopy was used to probe the site specific information of the $K_{0.84}Fe_{1.99}Se_2$ superconductor. Possibility of coexistence of superconductivity and magnetism is discussed. A spin excitation gap, $\Delta E \approx$5\,meV, is observed by analyzing the temperature dependence of the hyperfine magnetic field (HMF) at the iron site within the spin wave theory. Using a simple model suggested in the literature, the temperature dependence of the HMF is well reproduced, suggesting… Expand
7 Citations

#### Figures from this paper

Phase separation and magnetic order in the Tl0.75K0.25Fe1.86Se2 superconductor studied by Mössbauer spectroscopy
• Chemistry
• 2013
Abstract The results of a 57 Fe Mossbauer spectroscopy study between 4.4 and 518.2 K and in external magnetic fields of superconducting Tl 0.75 K 0.25 Fe 1.86 Se 2 single crystals are reported.Expand
Interplay between magnetism and superconductivity in iron-chalcogenide superconductors: crystal growth and characterizations
• Physics, Materials Science
• 2011
In this review, we present a summary of the results on single crystal growth of two types of iron-chalcogenide superconductors, Fe(1+y)Te(1-x)Se(x) (11), and A(x)Fe(2-y)Se(2) (A= K, Rb, Cs, Tl, Tl/K,Expand
Local microscopic properties and annealing effect of Rb0.85Fe1.9Se2 single crystals.
• K. Szymański, +5 authors A. Wisniewski
• Materials Science, Medicine
• Journal of physics. Condensed matter : an Institute of Physics journal
• 2017
The softening of the nonmagnetic one, having clearly more soft dynamics, was found to be gained further by the annealing of the single crystals at phase separation temperature, T p, leading to the reduction of size of initially separated domains and their more homogenous distribution in the tetragonal matrix of the studied sample. Expand
57Fe Mössbauer spectroscopic studies of single-crystalline KxFe2-yS2 and KxFe2-ySe2
• Chemistry
• 2016
We have investigated the physical properties of single-crystalline KxFe2-yS2 and KxFe2-ySe2 samples using 57Fe Mössbauer spectroscopy. The observed 57Fe Mössbauer spectra were reconstructed using aExpand
New ternary ThCr2Si2-type iron–selenide superconducting materials: Synthesis, properties and simulations
Abstract Very recently, the first ThCr2Si2-type ternary superconductor K0.8Fe2Se2 with enhanced TC ∼ 31 K has been discovered. This finding has stimulated much activity in search for relatedExpand
Determination of hyperfine fields orientation in nuclear probe techniques.
• Chemistry, Medicine
• Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy
• 2017
One of the most popular nuclear probes, 57Fe is used for the investigation of orientations of hyperfine fields and also for the determination of other important properties, including its signs, which can be unambiguously determined. Expand
Spin excitations in a K0.84Fe1.99Se2 superconductor as studied by Mössbauer spectroscopy
• Physics
• 2012
Mossbauer spectroscopy was used to probe the site-specific information of a K0.84Fe1.99Se2 superconductor. A spin excitation gap, ΔE ≈ 5.5 meV, is observed by analyzing the temperature dependence ofExpand

#### References

SHOWING 1-10 OF 33 REFERENCES
Superconducting properties of single-crystalline A x Fe 2-y Se 2 (A=Rb, K) studied using muon spin spectroscopy
We report on the superconducting properties of ${A}_{x}$Fe${}_{2\ensuremath{-}y}$Se${}_{2}$ ($A$$=$Rb, K) single crystals studied with the muon spin relaxation or rotation ($\ensuremath{\mu}$SR)Expand
Superconductivity at 32 K in single-crystalline Rb x Fe 2 − y Se 2
We successfully grew the high-quality single crystal of Rb${}_{0.88}$Fe${}_{1.81}$Se${}_{2}$, which shows a clear superconducting transition in magnetic susceptibility and electrical resistivity.Expand
Nanoscale phase separation in the iron chalcogenide superconductor K 0 . 8 Fe 1 . 6 Se 2 as seen via scanning nanofocused x-ray diffraction
Advanced synchrotron radiation focusing down to a size of 300 nm has been used to visualize nanoscale phase separation in the K${}_{0.8}$Fe${}_{1.6}$Se${}_{2}$ superconducting system using scanningExpand
Spin waves and magnetic exchange interactions in insulating Rb(0.89)Fe(1.58)Se(2).
The results suggest a common origin for the magnetism of all the Fe-based superconductors, despite having different ground states and antiferromagnetic orderings. Expand
57Fe Mössbauer study of magnetic ordering in superconducting K0.80Fe1.76Se2.00 single crystals
The magnetic ordering of superconducting single crystals of K_0.85Fe_1.83Se_2.09 has been studied between 10K and 550K using 57-Fe Mossbauer spectroscopy. Despite being superconducting below T_scExpand
Coexistence of magnetism and superconductivity in the iron-based compound Cs0.8(FeSe0.98)2.
Data from muon-spin rotation and relaxation, electrical resistivity, magnetization and differential scanning calorimetry measurements performed on a high-quality single crystal indicate a microscopic coexistence between the superconducting phase and a strong magnetic phase. Expand
Phase separation in superconducting and antiferromagnetic Rb0.8Fe1.6Se2 probed by M
57Fe-M\"ossbauer studies of superconducting Rb0.8Fe1.6Se2.0 with TC = 32.4 K were performed on single-crystalline and polycrystalline samples in the temperature range 4.2 K to 295 K. They reveal theExpand
A Novel Large Moment Antiferromagnetic Order in K 0.8 Fe 1.6 Se 2 Superconductor
The discovery of cuprate high TC superconductors has inspired the search for unconventional superconductors in magnetic materials. A successful recipe has been to suppress long-range order in aExpand
Mössbauer and magnetization studies of A0.8Fe2 − ySe2 (A = K, Rb and K/Tl)
• Materials Science
• 2011
57Fe Mossbauer spectroscopy and dc magnetization studies of the magneto-superconducting tetragonal A0.8Fe2 − ySe2 (A = K, Rb and K/Tl, y = 0.2–0.3) materials at temperatures of 5–550 K have beenExpand
Evolution of the resonance and incommensurate spin fluctuations in superconducting YBa(2)Cu(3)O(6+x)
• Physics
• 2001
Polarized and unpolarized neutron triple-axis spectrometry was used to study the dynamical magnetic susceptibility chi"(q,omega) as a function of energy ((h) over bar omega) and wave vector (q) in aExpand