Abstract:We investigated the dependence of the seed (Ta/Pt, Ta/Au) and capping (Pt/Ta, Au/Ta) layers on spin pumping effect in the ferromagnetic 3 nm thick Co thin film using ferromagnetic resonance spectroscopy. The data is fitted with Kittel's equation to evaluate damping constant and g-factor. A strong dependence of seed and capping layers on spin pumping has been discussed. The value of damping constant (α) is found to be relatively large i.e. 0.0326±0.0008 for the Ta(3)/Pt(3)/Co(3)/Pt(3)/Ta(3) (nm) multilayer structure, while it is 0.0104±0.0003 for Ta(3)/Co(3)/Ta(3) (nm). Increase in α is observed due to Pt layer that works as a good sink for spins due to high spin orbit coupling. In addition, we measured the effective spin conductance  g = 2.00 ± 0.08 × 10 18 m -2 for the tri-layer structure Pt(3)/Co(3)/Pt(3) (nm) as a result of the enhancement in α relative to its bulk value.We observed that the evaluated g-factor decreases as effective demagnetizing magnetic field increases in all the studied samples. The azimuthal dependence of magnetic resonance field and line width showed relatively high anisotropy in the tri-layer Ta(3)/Co(3)/Ta(3) (nm) structure.

Spintronics exploiting pure spin current in ferromagnetic (FM)/heavy metals (HM) is a subject of intense research. Topological insulators having spin momentum locked surface states exhibit high spin–orbit coupling and thus possess a huge potential to replace the HM like Pt, Ta, W, etc. In this context, the spin pumping phenomenon in Bi2Se3/CoFeB bilayers has been investigated. Bi2Se3 thin films are fabricated by electron beam evaporation method on Si (100) substrate. In order to confirm the topological nature of Bi2Se3, low temperature magnetotransport measurement on a 30 nm thick Bi2Se3 film which shows 10% magnetoresistance (MR) at 1.5 K has been performed. A linear increase in MR with applied magnetic field indicates the presence of spin momentum‐locked surface states. A voltage has been measured at room temperature to quantify the spin pumping which is generated via inverse spin Hall effect (ISHE). For the separation of spin rectification effects mainly produced by the FM CoFeB layer, in plane angular dependence of the dc voltage with respect to applied magnetic field has been measured. Our analysis reveals that spin pumping induced ISHE is the dominant contribution in the measured voltage.

Bi 2 Se 3 is a well-established topological insulator (TI) having spin momentum locked Dirac surface states at room temperature and predicted to exhibit high spin to charge conversion efficiency (SCCE) for spintronics applications. The SCCE in TIs is characterized by an inverse Edelstein effect length (λ IREE ). We report an λ IREE of ∼0.36 nm, which is the highest ever observed in Bi 2 Se 3 . Here, we performed spin pumping and inverse spin Hall effect (ISHE) in an electron beam-evaporated Bi 2 Se 3 / CoFeB bilayer. The Bi 2 Se 3 thickness dependence of λ IREE , perpendicular surface anisotropy (K S ), spin mixing conductance, and spin Hall angle confirmed that spin to charge conversion is due to spin momentum locked Dirac surface states. We propose that the role of surface states in SCCE can be understood by the evaluation of K S . The SCCE is found to be high when the value of K S is small.

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Dzyaloshinskii-Moriya interaction (DMI) manifesting in asymmetric layered ferromagnetic films gives rise to non-colinear spin structures stabilizing magnetization configurations with nontrivial topology. In this work magnetization reversal, magnetic domain alignment, and...

Objective: The objective of the study was to study various renal manifestations in sickle cell disease (SCD) and to establish a cause and effect relationship with the evaluation of risk factors. Methods: This prospective observational cross-sectional study was conducted on 82 SCD patients belonging to the age group of 15–50 years of both the genders over a period of 2 years from January 2019 to December 2020 in MKCG Medical College and Hospital, Berhampur, Odisha, India. Eighty-two patients, 32 (39.02%) having sickle cell anemia (SCA) and 50 (60.98%) having sickle cell trait (SCT), admitted to medicine and nephrology wards of the hospital were included in this study. SCD patients with other hemolytic anemia and with renal congenital/structural abnormality and patients with systemic diseases such as diabetes mellitus, systemic hypertension, and systemic lupus erythematosus were excluded from the study. Various laboratory investigations such as complete blood count, hemoglobin (Hb), serum sodium, serum potassium, serum urea, serum creatinine, fasting blood sugar, erythrocyte sedimentation rate, liver function test, urine routine, and microscopic test were carried out. Diagnosis of SCD patients was based on sickling test and high-performance liquid chromatography testing. Radiologic imaging (Sonography for renal changes) was done at radiodiagnosis department of the hospital. Results: Glomerular and tubular dysfunction was more in SCA (Hb SS) patients than SCT (Hb AS) patients and the abnormality was more in patients in crisis. Albuminuria in 78.12%, hematuria in 46.87%, cast and crystal in 28.12%, epithelial cell in 31.25%, and hyposthenuria in 56.25% were found in SCA patients. In SCT patients, albuminuria in 38%, hematuria in 16%, cast and crystal in 22%, epithelial cell in 12%, and hyposthenuria in 24% were found. All the above findings were more in percentages in crisis patients of both the groups. In SCA, 37.5% and in SCT, 2% were found to have chronic kidney disease. Conclusion: Renal involvement in the form of glomerular and tubular dysfunction occur in SCD and more in crisis patients, leading to renal complications, and end-stage renal disease.

: Retroperitoneal masses constitute a heterogeneous group of uncommon lesions and represent a challenge due to overlapping imaging findings. Most are malignant lesions. To evaluate the role of CT in the detection, localization and characterization of retroperitoneal masses and to compare and correlate with post-surgical evaluation and histological evaluation whenever possible.: The cross-sectional study carried out in the Department of Radiodiagnosis for a period of 2 years. Present study involved 50 patients of either sex belonging to various age groups. The CT scan findings were correlated with the findings at surgery and histopathological examination. : Renal masses were the most common retroperitoneal mass(48%). Renal cell carcinoma was the most common renal tumour (66.6%)and pancreatic adenocarcinoma was the most common pancreatic tumour (68.7%). Majority of cases of retroperitoneal mass were in the age group 51-70 years. Males were affected more than females in a ratio of 1.94: 1. Mass in the abdomen was the most common clinical presenting feature (40%). CT accuracy in the diagnosis of retroperitoneal tumours was 96%. CT is an essential diagnostic modality in diagnosing and characterizing retroperitoneal masses. It establishes the location of such masses and shows in great detail the associated findings.

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