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Pengcheng Dai - One of the best experts on this subject based on the ideXlab platform.
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spin fluctuation anisotropy as a probe of orbital selective Hole Electron quasiparticle excitations in detwinned ba fe 1 x co x 2 as 2
Physical Review B, 2019Co-Authors: Long Tian, Panpan Liu, H C Walker, U Stuhr, Guotai Tan, Pengcheng DaiAbstract:We use inelastic neutron scattering to study spin excitation anisotropy in mechanically detwinned Ba(Fe1-xCox)2As2 with x = 0.048 and 0.054. Both samples exhibit a tetragonal-to-orthorhombic structural transition at Ts, a collinear static antiferromagnetic (AF) order at wave vector Q1 = QAF = (1, 0) below the Neel temperature TN, and superconductivity below Tc (Ts > TN > Tc). In the high temperature paramagnetic tetragonal phase (T > Ts), spin excitations centered at Q1 and Q2 = (0, 1) are gapless and have four-fold (C4) rotational symmetry. On cooling to below TN but above Tc, spin excitations become highly anisotropic, developing a gap at Q2 but still are gapless at Q1. Upon entering into the superconducting state, a neutron spin resonance appears at Q1 with no magnetic scattering at Q2. By comparing these results with those from angle resolved photoemission spectroscopy experiments, we conclude that the anisotropic shift of the dyz and dxz bands in detwinned Ba(Fe1-xCox)2As2 below Ts is associated with the spin excitation anisotropy, and the superconductivity-induced resonance arises from the Electron-Hole Fermi surface nesting of quasiparticles with the dyz orbital characters.
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neutron spin resonance as a probe of fermi surface nesting and superconducting gap symmetry in ba0 67k0 33 fe1 xcox 2as2
Physical Review B, 2018Co-Authors: Rui Zhang, Weiyi Wang, Thomas Maier, Meng Wang, M B Stone, Songxue Chi, Barry Winn, Pengcheng DaiAbstract:We use inelastic neutron scattering to study energy and wave vector dependence of the superconductivity-induced resonance in Hole-doped Ba$_{0.67}$K$_{0.33}$(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$ ($x=0,0.08$ with $T_c\approx 37, 28$ K, respectively). In previous work on Electron-doped Ba(Fe$_{0.963}$Ni$_{0.037}$)$_2$As$_2$ ($T_N=26$ K and $T_c=17$ K), the resonance is found to peak sharply at the antiferromagnetic (AF) ordering wave vector ${\bf Q}_{\rm AF}$ along the longitudinal direction, but disperses upwards away from ${\bf Q}_{\rm AF}$ along the transverse direction. For Hole doped $x=0, 0.08$ without AF order, we find that the resonance displays ring-like upward dispersion away from ${\bf Q}_{\rm AF}$ along both the longitudinal and transverse directions. By comparing these results with calculations using the random phase approximation, we conclude that the dispersive resonance is a direct signature of isotropic superconducting gaps arising from nested Hole-Electron Fermi surfaces.
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neutron spin resonance as a probe of fermi surface nesting and superconducting gap symmetry in ba 0 67 k 0 33 fe 1 x co x 2 as 2
Physical Review B, 2018Co-Authors: Rui Zhang, Weiyi Wang, Thomas Maier, Meng Wang, M B Stone, Songxue Chi, Barry Winn, Pengcheng DaiAbstract:We use inelastic neutron scattering to study energy and wave vector dependence of the superconductivity-induced resonance in Hole-doped Ba$_{0.67}$K$_{0.33}$(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$ ($x=0,0.08$ with $T_c\approx 37, 28$ K, respectively). In previous work on Electron-doped Ba(Fe$_{0.963}$Ni$_{0.037}$)$_2$As$_2$ ($T_N=26$ K and $T_c=17$ K), the resonance is found to peak sharply at the antiferromagnetic (AF) ordering wave vector ${\bf Q}_{\rm AF}$ along the longitudinal direction, but disperses upwards away from ${\bf Q}_{\rm AF}$ along the transverse direction. For Hole doped $x=0, 0.08$ without AF order, we find that the resonance displays ring-like upward dispersion away from ${\bf Q}_{\rm AF}$ along both the longitudinal and transverse directions. By comparing these results with calculations using the random phase approximation, we conclude that the dispersive resonance is a direct signature of isotropic superconducting gaps arising from nested Hole-Electron Fermi surfaces.
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neutron spin resonance as a probe of fermi surface nesting and superconducting gap symmetry in ba 0 67 k 0 33 fe 1 x co x 2 as 2
Physical Review B, 2018Co-Authors: Rui Zhang, Weiyi Wang, Thomas Maier, Meng Wang, M B Stone, Songxue Chi, Barry Winn, Pengcheng DaiAbstract:We use inelastic neutron scattering to study the energy and wave-vector dependence of the superconductivity-induced resonance in Hole-doped ${\mathrm{Ba}}_{0.67}{\mathrm{K}}_{0.33}{({\mathrm{Fe}}_{1\ensuremath{-}x}{\mathrm{Co}}_{x})}_{2}{\mathrm{As}}_{2}$ ($x=0$ and 0.08 with ${T}_{c}\ensuremath{\approx}37$ and 28 K, respectively). In previous work on Electron-doped $\mathrm{Ba}{({\mathrm{Fe}}_{0.963}{\mathrm{Ni}}_{0.037})}_{2}{\mathrm{As}}_{2}$ (${T}_{N}=26$ K and ${T}_{c}=17$ K), the resonance is found to peak sharply at the antiferromagnetic (AF) ordering wave vector ${\mathbf{Q}}_{\mathrm{AF}}$ along the longitudinal direction, but disperses upwards away from ${\mathbf{Q}}_{\mathrm{AF}}$ along the transverse direction [Kim et al., Phys. Rev. Lett. 110, 177002 (2013)]. For Hole-doped $x=0$ and 0.08 without AF order, we find that the resonance displays a ringlike upward dispersion away from ${\mathbf{Q}}_{\mathrm{AF}}$ along both the longitudinal and transverse directions. By comparing these results with calculations using the random phase approximation, we conclude that the dispersive resonance is a direct signature of isotropic superconducting gaps arising from nested Hole-Electron Fermi surfaces.
Rui Zhang - One of the best experts on this subject based on the ideXlab platform.
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neutron spin resonance as a probe of fermi surface nesting and superconducting gap symmetry in ba0 67k0 33 fe1 xcox 2as2
Physical Review B, 2018Co-Authors: Rui Zhang, Weiyi Wang, Thomas Maier, Meng Wang, M B Stone, Songxue Chi, Barry Winn, Pengcheng DaiAbstract:We use inelastic neutron scattering to study energy and wave vector dependence of the superconductivity-induced resonance in Hole-doped Ba$_{0.67}$K$_{0.33}$(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$ ($x=0,0.08$ with $T_c\approx 37, 28$ K, respectively). In previous work on Electron-doped Ba(Fe$_{0.963}$Ni$_{0.037}$)$_2$As$_2$ ($T_N=26$ K and $T_c=17$ K), the resonance is found to peak sharply at the antiferromagnetic (AF) ordering wave vector ${\bf Q}_{\rm AF}$ along the longitudinal direction, but disperses upwards away from ${\bf Q}_{\rm AF}$ along the transverse direction. For Hole doped $x=0, 0.08$ without AF order, we find that the resonance displays ring-like upward dispersion away from ${\bf Q}_{\rm AF}$ along both the longitudinal and transverse directions. By comparing these results with calculations using the random phase approximation, we conclude that the dispersive resonance is a direct signature of isotropic superconducting gaps arising from nested Hole-Electron Fermi surfaces.
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neutron spin resonance as a probe of fermi surface nesting and superconducting gap symmetry in ba 0 67 k 0 33 fe 1 x co x 2 as 2
Physical Review B, 2018Co-Authors: Rui Zhang, Weiyi Wang, Thomas Maier, Meng Wang, M B Stone, Songxue Chi, Barry Winn, Pengcheng DaiAbstract:We use inelastic neutron scattering to study energy and wave vector dependence of the superconductivity-induced resonance in Hole-doped Ba$_{0.67}$K$_{0.33}$(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$ ($x=0,0.08$ with $T_c\approx 37, 28$ K, respectively). In previous work on Electron-doped Ba(Fe$_{0.963}$Ni$_{0.037}$)$_2$As$_2$ ($T_N=26$ K and $T_c=17$ K), the resonance is found to peak sharply at the antiferromagnetic (AF) ordering wave vector ${\bf Q}_{\rm AF}$ along the longitudinal direction, but disperses upwards away from ${\bf Q}_{\rm AF}$ along the transverse direction. For Hole doped $x=0, 0.08$ without AF order, we find that the resonance displays ring-like upward dispersion away from ${\bf Q}_{\rm AF}$ along both the longitudinal and transverse directions. By comparing these results with calculations using the random phase approximation, we conclude that the dispersive resonance is a direct signature of isotropic superconducting gaps arising from nested Hole-Electron Fermi surfaces.
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neutron spin resonance as a probe of fermi surface nesting and superconducting gap symmetry in ba 0 67 k 0 33 fe 1 x co x 2 as 2
Physical Review B, 2018Co-Authors: Rui Zhang, Weiyi Wang, Thomas Maier, Meng Wang, M B Stone, Songxue Chi, Barry Winn, Pengcheng DaiAbstract:We use inelastic neutron scattering to study the energy and wave-vector dependence of the superconductivity-induced resonance in Hole-doped ${\mathrm{Ba}}_{0.67}{\mathrm{K}}_{0.33}{({\mathrm{Fe}}_{1\ensuremath{-}x}{\mathrm{Co}}_{x})}_{2}{\mathrm{As}}_{2}$ ($x=0$ and 0.08 with ${T}_{c}\ensuremath{\approx}37$ and 28 K, respectively). In previous work on Electron-doped $\mathrm{Ba}{({\mathrm{Fe}}_{0.963}{\mathrm{Ni}}_{0.037})}_{2}{\mathrm{As}}_{2}$ (${T}_{N}=26$ K and ${T}_{c}=17$ K), the resonance is found to peak sharply at the antiferromagnetic (AF) ordering wave vector ${\mathbf{Q}}_{\mathrm{AF}}$ along the longitudinal direction, but disperses upwards away from ${\mathbf{Q}}_{\mathrm{AF}}$ along the transverse direction [Kim et al., Phys. Rev. Lett. 110, 177002 (2013)]. For Hole-doped $x=0$ and 0.08 without AF order, we find that the resonance displays a ringlike upward dispersion away from ${\mathbf{Q}}_{\mathrm{AF}}$ along both the longitudinal and transverse directions. By comparing these results with calculations using the random phase approximation, we conclude that the dispersive resonance is a direct signature of isotropic superconducting gaps arising from nested Hole-Electron Fermi surfaces.
Thomas Maier - One of the best experts on this subject based on the ideXlab platform.
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neutron spin resonance as a probe of fermi surface nesting and superconducting gap symmetry in ba0 67k0 33 fe1 xcox 2as2
Physical Review B, 2018Co-Authors: Rui Zhang, Weiyi Wang, Thomas Maier, Meng Wang, M B Stone, Songxue Chi, Barry Winn, Pengcheng DaiAbstract:We use inelastic neutron scattering to study energy and wave vector dependence of the superconductivity-induced resonance in Hole-doped Ba$_{0.67}$K$_{0.33}$(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$ ($x=0,0.08$ with $T_c\approx 37, 28$ K, respectively). In previous work on Electron-doped Ba(Fe$_{0.963}$Ni$_{0.037}$)$_2$As$_2$ ($T_N=26$ K and $T_c=17$ K), the resonance is found to peak sharply at the antiferromagnetic (AF) ordering wave vector ${\bf Q}_{\rm AF}$ along the longitudinal direction, but disperses upwards away from ${\bf Q}_{\rm AF}$ along the transverse direction. For Hole doped $x=0, 0.08$ without AF order, we find that the resonance displays ring-like upward dispersion away from ${\bf Q}_{\rm AF}$ along both the longitudinal and transverse directions. By comparing these results with calculations using the random phase approximation, we conclude that the dispersive resonance is a direct signature of isotropic superconducting gaps arising from nested Hole-Electron Fermi surfaces.
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neutron spin resonance as a probe of fermi surface nesting and superconducting gap symmetry in ba 0 67 k 0 33 fe 1 x co x 2 as 2
Physical Review B, 2018Co-Authors: Rui Zhang, Weiyi Wang, Thomas Maier, Meng Wang, M B Stone, Songxue Chi, Barry Winn, Pengcheng DaiAbstract:We use inelastic neutron scattering to study energy and wave vector dependence of the superconductivity-induced resonance in Hole-doped Ba$_{0.67}$K$_{0.33}$(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$ ($x=0,0.08$ with $T_c\approx 37, 28$ K, respectively). In previous work on Electron-doped Ba(Fe$_{0.963}$Ni$_{0.037}$)$_2$As$_2$ ($T_N=26$ K and $T_c=17$ K), the resonance is found to peak sharply at the antiferromagnetic (AF) ordering wave vector ${\bf Q}_{\rm AF}$ along the longitudinal direction, but disperses upwards away from ${\bf Q}_{\rm AF}$ along the transverse direction. For Hole doped $x=0, 0.08$ without AF order, we find that the resonance displays ring-like upward dispersion away from ${\bf Q}_{\rm AF}$ along both the longitudinal and transverse directions. By comparing these results with calculations using the random phase approximation, we conclude that the dispersive resonance is a direct signature of isotropic superconducting gaps arising from nested Hole-Electron Fermi surfaces.
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neutron spin resonance as a probe of fermi surface nesting and superconducting gap symmetry in ba 0 67 k 0 33 fe 1 x co x 2 as 2
Physical Review B, 2018Co-Authors: Rui Zhang, Weiyi Wang, Thomas Maier, Meng Wang, M B Stone, Songxue Chi, Barry Winn, Pengcheng DaiAbstract:We use inelastic neutron scattering to study the energy and wave-vector dependence of the superconductivity-induced resonance in Hole-doped ${\mathrm{Ba}}_{0.67}{\mathrm{K}}_{0.33}{({\mathrm{Fe}}_{1\ensuremath{-}x}{\mathrm{Co}}_{x})}_{2}{\mathrm{As}}_{2}$ ($x=0$ and 0.08 with ${T}_{c}\ensuremath{\approx}37$ and 28 K, respectively). In previous work on Electron-doped $\mathrm{Ba}{({\mathrm{Fe}}_{0.963}{\mathrm{Ni}}_{0.037})}_{2}{\mathrm{As}}_{2}$ (${T}_{N}=26$ K and ${T}_{c}=17$ K), the resonance is found to peak sharply at the antiferromagnetic (AF) ordering wave vector ${\mathbf{Q}}_{\mathrm{AF}}$ along the longitudinal direction, but disperses upwards away from ${\mathbf{Q}}_{\mathrm{AF}}$ along the transverse direction [Kim et al., Phys. Rev. Lett. 110, 177002 (2013)]. For Hole-doped $x=0$ and 0.08 without AF order, we find that the resonance displays a ringlike upward dispersion away from ${\mathbf{Q}}_{\mathrm{AF}}$ along both the longitudinal and transverse directions. By comparing these results with calculations using the random phase approximation, we conclude that the dispersive resonance is a direct signature of isotropic superconducting gaps arising from nested Hole-Electron Fermi surfaces.
Meng Wang - One of the best experts on this subject based on the ideXlab platform.
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neutron spin resonance as a probe of fermi surface nesting and superconducting gap symmetry in ba0 67k0 33 fe1 xcox 2as2
Physical Review B, 2018Co-Authors: Rui Zhang, Weiyi Wang, Thomas Maier, Meng Wang, M B Stone, Songxue Chi, Barry Winn, Pengcheng DaiAbstract:We use inelastic neutron scattering to study energy and wave vector dependence of the superconductivity-induced resonance in Hole-doped Ba$_{0.67}$K$_{0.33}$(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$ ($x=0,0.08$ with $T_c\approx 37, 28$ K, respectively). In previous work on Electron-doped Ba(Fe$_{0.963}$Ni$_{0.037}$)$_2$As$_2$ ($T_N=26$ K and $T_c=17$ K), the resonance is found to peak sharply at the antiferromagnetic (AF) ordering wave vector ${\bf Q}_{\rm AF}$ along the longitudinal direction, but disperses upwards away from ${\bf Q}_{\rm AF}$ along the transverse direction. For Hole doped $x=0, 0.08$ without AF order, we find that the resonance displays ring-like upward dispersion away from ${\bf Q}_{\rm AF}$ along both the longitudinal and transverse directions. By comparing these results with calculations using the random phase approximation, we conclude that the dispersive resonance is a direct signature of isotropic superconducting gaps arising from nested Hole-Electron Fermi surfaces.
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neutron spin resonance as a probe of fermi surface nesting and superconducting gap symmetry in ba 0 67 k 0 33 fe 1 x co x 2 as 2
Physical Review B, 2018Co-Authors: Rui Zhang, Weiyi Wang, Thomas Maier, Meng Wang, M B Stone, Songxue Chi, Barry Winn, Pengcheng DaiAbstract:We use inelastic neutron scattering to study energy and wave vector dependence of the superconductivity-induced resonance in Hole-doped Ba$_{0.67}$K$_{0.33}$(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$ ($x=0,0.08$ with $T_c\approx 37, 28$ K, respectively). In previous work on Electron-doped Ba(Fe$_{0.963}$Ni$_{0.037}$)$_2$As$_2$ ($T_N=26$ K and $T_c=17$ K), the resonance is found to peak sharply at the antiferromagnetic (AF) ordering wave vector ${\bf Q}_{\rm AF}$ along the longitudinal direction, but disperses upwards away from ${\bf Q}_{\rm AF}$ along the transverse direction. For Hole doped $x=0, 0.08$ without AF order, we find that the resonance displays ring-like upward dispersion away from ${\bf Q}_{\rm AF}$ along both the longitudinal and transverse directions. By comparing these results with calculations using the random phase approximation, we conclude that the dispersive resonance is a direct signature of isotropic superconducting gaps arising from nested Hole-Electron Fermi surfaces.
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neutron spin resonance as a probe of fermi surface nesting and superconducting gap symmetry in ba 0 67 k 0 33 fe 1 x co x 2 as 2
Physical Review B, 2018Co-Authors: Rui Zhang, Weiyi Wang, Thomas Maier, Meng Wang, M B Stone, Songxue Chi, Barry Winn, Pengcheng DaiAbstract:We use inelastic neutron scattering to study the energy and wave-vector dependence of the superconductivity-induced resonance in Hole-doped ${\mathrm{Ba}}_{0.67}{\mathrm{K}}_{0.33}{({\mathrm{Fe}}_{1\ensuremath{-}x}{\mathrm{Co}}_{x})}_{2}{\mathrm{As}}_{2}$ ($x=0$ and 0.08 with ${T}_{c}\ensuremath{\approx}37$ and 28 K, respectively). In previous work on Electron-doped $\mathrm{Ba}{({\mathrm{Fe}}_{0.963}{\mathrm{Ni}}_{0.037})}_{2}{\mathrm{As}}_{2}$ (${T}_{N}=26$ K and ${T}_{c}=17$ K), the resonance is found to peak sharply at the antiferromagnetic (AF) ordering wave vector ${\mathbf{Q}}_{\mathrm{AF}}$ along the longitudinal direction, but disperses upwards away from ${\mathbf{Q}}_{\mathrm{AF}}$ along the transverse direction [Kim et al., Phys. Rev. Lett. 110, 177002 (2013)]. For Hole-doped $x=0$ and 0.08 without AF order, we find that the resonance displays a ringlike upward dispersion away from ${\mathbf{Q}}_{\mathrm{AF}}$ along both the longitudinal and transverse directions. By comparing these results with calculations using the random phase approximation, we conclude that the dispersive resonance is a direct signature of isotropic superconducting gaps arising from nested Hole-Electron Fermi surfaces.
M B Stone - One of the best experts on this subject based on the ideXlab platform.
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neutron spin resonance as a probe of fermi surface nesting and superconducting gap symmetry in ba0 67k0 33 fe1 xcox 2as2
Physical Review B, 2018Co-Authors: Rui Zhang, Weiyi Wang, Thomas Maier, Meng Wang, M B Stone, Songxue Chi, Barry Winn, Pengcheng DaiAbstract:We use inelastic neutron scattering to study energy and wave vector dependence of the superconductivity-induced resonance in Hole-doped Ba$_{0.67}$K$_{0.33}$(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$ ($x=0,0.08$ with $T_c\approx 37, 28$ K, respectively). In previous work on Electron-doped Ba(Fe$_{0.963}$Ni$_{0.037}$)$_2$As$_2$ ($T_N=26$ K and $T_c=17$ K), the resonance is found to peak sharply at the antiferromagnetic (AF) ordering wave vector ${\bf Q}_{\rm AF}$ along the longitudinal direction, but disperses upwards away from ${\bf Q}_{\rm AF}$ along the transverse direction. For Hole doped $x=0, 0.08$ without AF order, we find that the resonance displays ring-like upward dispersion away from ${\bf Q}_{\rm AF}$ along both the longitudinal and transverse directions. By comparing these results with calculations using the random phase approximation, we conclude that the dispersive resonance is a direct signature of isotropic superconducting gaps arising from nested Hole-Electron Fermi surfaces.
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neutron spin resonance as a probe of fermi surface nesting and superconducting gap symmetry in ba 0 67 k 0 33 fe 1 x co x 2 as 2
Physical Review B, 2018Co-Authors: Rui Zhang, Weiyi Wang, Thomas Maier, Meng Wang, M B Stone, Songxue Chi, Barry Winn, Pengcheng DaiAbstract:We use inelastic neutron scattering to study energy and wave vector dependence of the superconductivity-induced resonance in Hole-doped Ba$_{0.67}$K$_{0.33}$(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$ ($x=0,0.08$ with $T_c\approx 37, 28$ K, respectively). In previous work on Electron-doped Ba(Fe$_{0.963}$Ni$_{0.037}$)$_2$As$_2$ ($T_N=26$ K and $T_c=17$ K), the resonance is found to peak sharply at the antiferromagnetic (AF) ordering wave vector ${\bf Q}_{\rm AF}$ along the longitudinal direction, but disperses upwards away from ${\bf Q}_{\rm AF}$ along the transverse direction. For Hole doped $x=0, 0.08$ without AF order, we find that the resonance displays ring-like upward dispersion away from ${\bf Q}_{\rm AF}$ along both the longitudinal and transverse directions. By comparing these results with calculations using the random phase approximation, we conclude that the dispersive resonance is a direct signature of isotropic superconducting gaps arising from nested Hole-Electron Fermi surfaces.
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neutron spin resonance as a probe of fermi surface nesting and superconducting gap symmetry in ba 0 67 k 0 33 fe 1 x co x 2 as 2
Physical Review B, 2018Co-Authors: Rui Zhang, Weiyi Wang, Thomas Maier, Meng Wang, M B Stone, Songxue Chi, Barry Winn, Pengcheng DaiAbstract:We use inelastic neutron scattering to study the energy and wave-vector dependence of the superconductivity-induced resonance in Hole-doped ${\mathrm{Ba}}_{0.67}{\mathrm{K}}_{0.33}{({\mathrm{Fe}}_{1\ensuremath{-}x}{\mathrm{Co}}_{x})}_{2}{\mathrm{As}}_{2}$ ($x=0$ and 0.08 with ${T}_{c}\ensuremath{\approx}37$ and 28 K, respectively). In previous work on Electron-doped $\mathrm{Ba}{({\mathrm{Fe}}_{0.963}{\mathrm{Ni}}_{0.037})}_{2}{\mathrm{As}}_{2}$ (${T}_{N}=26$ K and ${T}_{c}=17$ K), the resonance is found to peak sharply at the antiferromagnetic (AF) ordering wave vector ${\mathbf{Q}}_{\mathrm{AF}}$ along the longitudinal direction, but disperses upwards away from ${\mathbf{Q}}_{\mathrm{AF}}$ along the transverse direction [Kim et al., Phys. Rev. Lett. 110, 177002 (2013)]. For Hole-doped $x=0$ and 0.08 without AF order, we find that the resonance displays a ringlike upward dispersion away from ${\mathbf{Q}}_{\mathrm{AF}}$ along both the longitudinal and transverse directions. By comparing these results with calculations using the random phase approximation, we conclude that the dispersive resonance is a direct signature of isotropic superconducting gaps arising from nested Hole-Electron Fermi surfaces.