Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 7 of 7
Full-Text Articles in Engineering
Tailoring Spin-Orbit Torque In Diluted Magnetic Semiconductors, Hang Li, Xuhui Wang, Fatih Dogan, Aurelien Manchon
Tailoring Spin-Orbit Torque In Diluted Magnetic Semiconductors, Hang Li, Xuhui Wang, Fatih Dogan, Aurelien Manchon
Materials Science and Engineering Faculty Research & Creative Works
We study the spin orbit torque arising from an intrinsic linear Dresselhaus spin-orbit coupling in a single layer III-V diluted magnetic semiconductor. We investigate the transport properties and spin torque using the linear response theory, and we report here: (1) a strong correlation exists between the angular dependence of the torque and the anisotropy of the Fermi surface; (2) the spin orbit torque depends nonlinearly on the exchange coupling. Our findings suggest the possibility to tailor the spin orbit torque magnitude and angular dependence by structural design.
Neutron Structural Studies On The Superconducting (Nd₁₋ₓcax)(Ba₁.₆La₀.₄)Cu₃Oz System, Amish G. Joshi, R. G. Kulkarni, William B. Yelon, Ram Prasad, M. R. Gonal
Neutron Structural Studies On The Superconducting (Nd₁₋ₓcax)(Ba₁.₆La₀.₄)Cu₃Oz System, Amish G. Joshi, R. G. Kulkarni, William B. Yelon, Ram Prasad, M. R. Gonal
Physics Faculty Research & Creative Works
We have investigated the influence of Ca ion substitution on the structural and superconducting properties of (Nd1−xCax)(Ba1.6La0.4)Cu3Oz system. Magnetization, x-ray diffraction, and neutron diffraction studies have been carried out on a series of compounds with x=0.0-0.6. The superconducting transition temperature Tc, determined from magnetization measurements, increases with increasing Ca2+ substitution. Neutron diffraction studies reveal that these compounds crystallize in a tetragonal structure (space group P4/mmm). A detailed analysis of the neutron diffraction data reveals that Ca and La ions are intermixed at the nominal Ba and Nd sites. While a major fraction of Ca ions occupy the usual Nd site, …
Competing Magnetic Interactions In The Intermetallic Compound Ho₂Mn₃Si₅, R. Nirmala, A. V. Morozkin, Jagat Lamsal, Zili Chu, V. Sankaranarayanan, K. Sethupathi, Y. Yamamoto, H. Hori, William B. Yelon, Satish K. Malik
Competing Magnetic Interactions In The Intermetallic Compound Ho₂Mn₃Si₅, R. Nirmala, A. V. Morozkin, Jagat Lamsal, Zili Chu, V. Sankaranarayanan, K. Sethupathi, Y. Yamamoto, H. Hori, William B. Yelon, Satish K. Malik
Physics Faculty Research & Creative Works
The compound Ho2Mn3Si5 exhibits multiple magnetic transitions: (i) an ordering at ~78 K, (ii) a second magnetic transition at ~16 K, and (iii) an anomaly at ~4 K. Its paramagnetic Curie temperature is found to be small but positive. Assuming a free ion effective paramagnetic moment of 10.6µB for Ho3+ ion, the effective paramagnetic moment per Mn in this compound is calculated to be 1.73µB, which indicates the itinerant nature of Mn d electrons. The various transitions in magnetization data are perhaps due to the ordering of rare earth and Mn moments. The magnetization at 2 K in applied fields …
Magnetic Ordering In The Rare Earth Intermetallic Compound Tb₂Ti₃Ge₄: Magnetization And Neutron Diffraction Studies, Satish K. Malik, Jagat Lamsal, R. L. De Almeida, S. Quezado, William B. Yelon, V. O. Garlea, A. V. Morozkin, R. Nirmala
Magnetic Ordering In The Rare Earth Intermetallic Compound Tb₂Ti₃Ge₄: Magnetization And Neutron Diffraction Studies, Satish K. Malik, Jagat Lamsal, R. L. De Almeida, S. Quezado, William B. Yelon, V. O. Garlea, A. V. Morozkin, R. Nirmala
Physics Faculty Research & Creative Works
Magnetization and neutron diffraction studies on a polycrystalline Tb2Ti3Ge4 sample (orthorhombic Sm5Ge4-type structure, space group Pnma, No. 62) have been carried out. This compound is found to order antiferromagnetically at ~18 K (TN). The magnetization (M) versus field (H) isotherms obtained at 2, 3, 5, and 10 K indicate a field-induced antiferromagnetic to ferromagnetic transition in fields of the order of 0.5 T. The saturation magnetization value at 2.5 K (M extrapolated to 1/H-->0) is only ~5.6µB/Tb3+, suggesting the possible presence of crystal field effects with or without a persisting antiferromagnetic component. Neutron powder diffraction data at 10 K …
Anomalous Magnetic Ordering In Prba₂Cu₄O₈ And Cmba₂Cu₃O₇, H. A. Blackstead, M. P. Smylie, William B. Yelon, Qingsheng Cai, Mehmet Kahveci
Anomalous Magnetic Ordering In Prba₂Cu₄O₈ And Cmba₂Cu₃O₇, H. A. Blackstead, M. P. Smylie, William B. Yelon, Qingsheng Cai, Mehmet Kahveci
Physics Faculty Research & Creative Works
A review of temperature-dependent magnetization data for nonsuperconducting PrBa2Cu4O8 and CmBa2Cu3O7 suggests that the failure of each to superconduct is related to the presence of Pr and Cm on their respective Ba sites. This defect is manifested, in each case, by short c-axis lattice parameters and anomalous high-temperature magnetic ordering which has been incorrectly attributed to ordering of the entire magnetic sublattice. Instead, it is shown that the anomalous high-temperature ordering as seen in the magnetization data is consistent with the ordering of magnetic ions substituted on the Ba site.
The Effect Of Cu-Doping On The Magnetic And Transport Properties Of La₀.₇Sr₀.₃Mno₃, M. S. Kim, Jinbo Yang, Qingsheng Cai, X.-D. Zhou, William B. Yelon, Paul Ernest Parris, William Joseph James
The Effect Of Cu-Doping On The Magnetic And Transport Properties Of La₀.₇Sr₀.₃Mno₃, M. S. Kim, Jinbo Yang, Qingsheng Cai, X.-D. Zhou, William B. Yelon, Paul Ernest Parris, William Joseph James
Physics Faculty Research & Creative Works
The effects of Cu-doping on the structural, magnetic, and transport properties of La0.7Sr0.3Mn1xCuxO3 (0<=x<=0.20) have been studied using neutron diffraction, magnetization, and magnetoresistance (MR) measurements. All samples show the rhombohedral structure with the R[overline 3]c space-group from 10 K to room temperature (RT). Neutron diffraction data suggest that some of the Cu ions have a Cu3+ state in these compounds. The substitution of Mn by Cu affects the MnO bond length and Mn-O-Mn bond angle resulting from the minimization of the distortion of the MnO6 octahedron. Resistivity measurements show that a metal to insulator transition occurs for the x>=0.15 samples. The x=0.15 sample shows the highest MR([approximate]80%), which might result from the co-existence of Cu3-Cu2+ and the dilution effect of Cu-doping on the double exchange interaction
Structural And Magnetic Properties Of Mrsr₂Y₁.₅Ce₀.₅Cu₂Oz (M-1222) Compounds With M = Fe And Co, V. P. S. Awana, Anurag Gupta, H. Kishan, Satish K. Malik, William B. Yelon, J. Lindén, M. Karppinen, H. Yamauchi, Darshan C. Kundaliya
Structural And Magnetic Properties Of Mrsr₂Y₁.₅Ce₀.₅Cu₂Oz (M-1222) Compounds With M = Fe And Co, V. P. S. Awana, Anurag Gupta, H. Kishan, Satish K. Malik, William B. Yelon, J. Lindén, M. Karppinen, H. Yamauchi, Darshan C. Kundaliya
Physics Faculty Research & Creative Works
The MSr2Y1.5Ce0.5Cu2Oz (M-1222) compounds, with M = Fe and Co, have been synthesized through a solid-state reaction route. Both compounds crystallize in a tetragonal structure (space group 14/mmm). A Rietveld structural refinement of the room-temperature neutron diffraction data for Fe-1222 reveals that nearly half the Fe remains at the M site, while the other half goes to the Cu site in the CuO2 planes. Existence of Fe at two different lattice sites is also confirmed by 57Fe Mössbauer spectroscopy from which it is inferred that ~50% of the total Fe occupies the Cu site in the CuO2 planes as Fe3+, …