NMR as a local probe for ferromagnetic quantum criticality in Fe- based systems

October 24, 2018

M. Majumder, P. Khuntia, A. Gippius¹, A. Strydom², C. Petrovic³, H. Yasuoka, M. Brando, H. Tjeng, F. Steglich, Y. Grin and M. Baenitz

Fig. 1 (a) 27(1/T1T) versus T for YbFe2Al10 in various applied magnetic fields. The solid line represents a calculation base on a model which includes a 3d- and a 4f – component. Fig.1 (b) shows the linear relation between the square root of the 3d part of the SLRR and the bulk susceptility and c and Fig. 1 (d) displays the field dependence of the SLRR at T = 2 K. Fig. 1 (c) gives the fluctuation time of the intermediate Yb3-d ion [9]. — Fig. 1 (a) ²⁷(1/T₁T) versus T for YbFe₂Al₁₀ in various applied magnetic fields. The solid line represents a calculation base on a model which includes a 3d- and a 4f – component. Fig.1 (b) shows the linear relation between the square root of the 3d part of the SLRR and the bulk susceptility and c and Fig. 1 (d) displays the field dependence of the SLRR at T = 2 K. Fig. 1 (c) gives the fluctuation time of the intermediate Yb^3-^d ion [9].

Fig. 1 (a) ²⁷(1/T₁T) versus T for YbFe₂Al₁₀ in various applied magnetic fields. The solid line represents a calculation base on a model which includes a 3d- and a 4f – component. Fig.1 (b) shows the linear relation between the square root of the 3d part of the SLRR and the bulk susceptility and c and Fig. 1 (d) displays the field dependence of the SLRR at T = 2 K. Fig. 1 (c) gives the fluctuation time of the intermediate Yb^3-^d ion [9].

Fig. 1 Temperature dependence of 71(1/T1T) measured at the Ga2- site of FeGa3-xGex for various Ge concentrations x. The solid lines correspond to a two component model with a (T-independent) conduction electron part and a (T-dependent) 3d-spin part. The dashed lines indicate the power laws of the bare spin part. Fig.1 (b) shows the T-4/3 power law in 71(1/T1T)3d for the critical sample and Fig. 1 (c) shows the 71(1/T1T)3d proportional to bulk susceptility relation for the ordered x=0.2 sample for T > TC [13]. — Fig. 1 Temperature dependence of ⁷¹(1/T₁T) measured at the Ga2- site of FeGa_3-xGe_x for various Ge concentrations x. The solid lines correspond to a two component model with a (T-independent) conduction electron part and a (T-dependent) 3d-spin part. The dashed lines indicate the power laws of the bare spin part. Fig.1 (b) shows the T^-4/3 power law in ⁷¹(1/T₁T)_3d for the critical sample and Fig. 1 (c) shows the ⁷¹(1/T₁T)_3d proportional to bulk susceptility relation for the ordered x=0.2 sample for T > T_C [13].

Fig. 1 Temperature dependence of ⁷¹(1/T₁T) measured at the Ga2- site of FeGa_3-xGe_x for various Ge concentrations x. The solid lines correspond to a two component model with a (T-independent) conduction electron part and a (T-dependent) 3d-spin part. The dashed lines indicate the power laws of the bare spin part. Fig.1 (b) shows the T^-4/3 power law in ⁷¹(1/T₁T)_3d for the critical sample and Fig. 1 (c) shows the ⁷¹(1/T₁T)_3d proportional to bulk susceptility relation for the ordered x=0.2 sample for T > T_C [13].

¹Physics Department, University of Johannesburg, PO Box 524, Auckland Park 2006, South Africa

²Department of Physics, Moscow State University,119991, Moscow, Russia

³Condensed Matter Physics, Brookhaven National Laboratory, Upton, NY 11973-5000, New York, USA

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