Giant Anomalous Hall Conductivity at the Pt/Cr₂O₃ Interface

The interface between a magnetic material and a heavy metal that has a large spin-orbit interaction is at the root of various spin-related phenomena. In this paper, we address the peculiar spin-dependent transport at a Pt/Cr₂O₃ interface by exploring the origin of the nonlinear anomalous Hall effect (AHE) in Pt/Cr₂O₃ bilayers. X-ray magnetic circular dichroism (XMCD) measurements show no appreciable magnetic moment at the interface originating from Cr 3d and Pt 5d orbitals, which could be associated with the AHE response. A possible interfacial magnetic moment M at the Pt/Cr₂O₃ interface, assumed from the detection limit of the XMCD measurements, yields an anomalous Hall conductivity (σAHE) per unit net magnetic moment (M),-σAHE/M, of 0.57 V-1, which is extraordinary large compared with that for general magnetic materials. Together with first-principles calculations, the results suggest the possibility of an intrinsic AHE in the Pt/Cr₂O₃ interface that does not rely on the net magnetic moment.T.Moriyama, Y.Shiratsuchi, T.Iino, et al. Giant Anomalous Hall Conductivity at the Pt/Cr₂O₃ Interface. Physical Review Applied 13, 034052 (2020); https://doi.org/10.1103/PhysRevApplied.13.034052

Giant gate modulation of antiferromagnetic spin reversal by the magnetoelectric effect

Ujimoto K., Sameshima H., Toyoki K., et al. Giant gate modulation of antiferromagnetic spin reversal by the magnetoelectric effect. NPG Asia Materials 16, 20 (2024); https://doi.org/10.1038/s41427-024-00541-z.In this study, using the Pt/Cr2O3/Pt epitaxial trilayer, we demonstrate the giant voltage modulation of the antiferromagnetic spin reversal and the voltage-induced 180° switching of the Néel vector in maintaining a permanent magnetic field. We obtained a significant modulation efficiency of the switching field, Δμ0HSW/ΔV (Δμ0HSW/ΔE), reaching a maximum of −500 mT/V (−4.80 T nm/V); this value was more than 50 times greater than that of the ferromagnetic-based counterparts. From the temperature dependence of the modulation efficiency, X-ray magnetic circular dichroism measurements and first-principles calculations, we showed that the origin of the giant modulation efficiency relied on the electric field modulation of the net magnetization due to the magnetoelectric effect. From the first-principles calculation and the thickness effect on the offset electric field, we found that the interfacial magnetoelectric effect emerged. Our demonstration reveals the energy-efficient and widely applicable operation of an antiferromagnetic spin based on a mechanism distinct from magnetic anisotropy control

High-Grade Renal MTSCC

Mucinous tubular and spindle cell carcinoma (MTSCC) is a rare subtype of renal cell carcinoma. Although usually indolent, high-grade MTSCC has been reported to exhibit an aggressive clinical course. Herein, we report a case of high-grade renal MTSCC. An 86-year-old man visited our hospital with fever and fatigue. Based on contrast-enhanced computed tomography findings, the patient was diagnosed with clinical stage T2aN0M0 right renal cell carcinoma and underwent laparoscopic radical nephrectomy. Histological examination showed tubular to tubulopapillary structures accompanied by mucinous stroma, suggesting high-grade renal MTSCC. He remained recurrence- and metastasis-free 6 months after nephrectomy. Since high-grade renal MTSCC may have an aggressive clinical course, such patients should be observed carefully after radical nephrectomy

Micropapillary Variant of UC in an HD Patient

The micropapillary variant of urothelial carcinoma (MPUC) is an aggressive form of urothelial carcinoma with high metastatic potential and a poor prognosis. Although various therapies have been reported, there is still no established treatment strategy for MPUC due to its rarity. The incidence of urinary tract malignancies is higher in patients undergoing hemodialysis (HD) than in healthy individuals. Here, we report the case of an 82-year-old man on HD with end-stage kidney disease who visited our hospital for macrohematuria. Cystoscopy followed by computed tomography and urine cytology revealed a sessile papillary tumor around the left bladder wall. We performed transurethral resection of the bladder tumor. Based on histopathological and imaging findings indicative of clinical-stage T3N0M0 MPUC, we performed radical cystectomy. Histopathology revealed a pathological stage T4aN0M0 MPUC. Two months after the cystectomy, the patient complained of constipation and painful defecation due to local recurrence and rectal invasion. While colostomy was performed to improve defecation 3 months after cystectomy, he did not receive any chemotherapy due to his progressively worsening general condition. Six months after cystectomy, he died following rapid metastases. Our findings, in this case, confirm that bladder cancer in HD patients tends to be pathologically more advanced. Therefore, regular screening is recommended for its early detection in HD patients

イオン移動度質量分析法を用いた気相クラスターイオンの幾何構造と化学反応の研究

要約のみTohoku University美齊津文典課

Isomer-separated photodissociation of large sized silicon and carbon cluster ions: Drift tube experiment combined with a tandem reflectron mass spectrometer for Si

Isomer-resolved multiphoton dissociations (PDs) with 4.66-eV laser photons were applied to carbon and silicon cluster cations, Cn+ (n = 32, 34, 36, and 38) and Sim+ (m = 24–27), in order to investigate correlations between the isomer structures and dissociation reactions. Cyclic and fullerene structures of Cn+ and prolate and spherical isomers of Sim+, which are the coexisting isomers in these size ranges, were separated by ion mobility spectrometry, followed by photolysis using a tandem reflectron mass spectrometer. Photofragment ion distributions were revealed to depend on the parent isomer structures. Dissociation mechanisms were discussed from the fragment ion distributions