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Programmable and non-volatile spin-based logic devices have attracted significant interest for use in logic circuits. Realization of logic operations via spin–orbit torque (SOT) driven magnetization switching could be a crucial step in the direction of building logic-in-memory architectures. In this work, we demonstrate experimentally, the realization of four logic operations in a heavy metal/ferrimagnet bilayer structure via SOT switching. We also propose a general scheme for choosing input parameters to achieve programmable logic operations. The bulk and tunable perpendicular magnetic anisotropy and relatively lower saturation magnetization in ferrimagnets are found to make them more energy efficient in performing logic operations, as compared to conventional ferromagnets. Thus, ferrimagnets are promising candidates for use in logic-in-memory architectures, leading to the realization of user-friendly spin logic devices in the future. [ABSTRACT FROM AUTHOR]

The broken inversion symmetry at the ferromagnet (FM)/heavy‐metal (HM) interface leads to spin‐dependent degeneracy of the energy band, forming spin‐polarized surface states. As a result, the interface serves as an effective medium for converting spin accumulation into 2D charge current through the inverse Rashba–Edelstein effect. Exploring and assessing this spin‐to‐charge conversion (SCC) phenomenon at the FM/HM interface can offer a promising avenue to surpass the presumed limits of SCC in bulk HM layers. Spintronic heterostructures are utilized as a platform to measure the SCC experienced by photoexcited spin currents. Therefore, FM/HM heterostructures emitting terahertz electric field upon illumination by femtosecond laser pulses enable quantitative measure of the ultrafast SCC process. This results demonstrate a robust interfacial spin‐to‐charge conversion (iSCC) within a synthetic antiferromagnetic heterostructure, specifically for the NiFe/Ru/NiFe configuration, by isolating the SCC contribution originating from the interface and the bulk heavy‐metal (HM). Through the measurements of the emitted terahertz pulse, the iSCC at the NiFe/Ru interface is identified to be ≈27% of the strength as compared to SCC from the highest spin‐Hall conducting heavy‐metal, Pt. The results thus highlight the significance of interfacial engineering as a promising pathway for achieving efficient ultrafast spintronic devices. [ABSTRACT FROM AUTHOR]

The impurity incorporation in host high spin-orbit coupling materials like platinum (Pt) has shown improved charge-to-spin conversion efficiency by modifying the up-spin and down-spin electrons trajectories via bending or skewing them in opposite directions. This enables efficient generation, manipulation, and transport of spin currents. In this study, we irradiated the Pt thin films with pulsed hot dense oxygen plasma in non-focus mode operation and analyzed the spin Hall angle of the oxygen plasma irradiated Pt films using spin torque ferromagnetic resonance (ST-FMR). Our results demonstrate a 2.4 times enhancement in the spin Hall angle after transient oxygen plasma treatment of Pt as compared to pristine Pt. This improvement might be because of the introduction of disorder and defects in the Pt lattice due to transient oxygen plasma processing, which enhanced the spin-orbit coupling and leads to more efficient charge-to-spin conversion without breaking the spin-orbit torque symmetries. Our findings offer a new method of dense plasma focus device-based modification of material for the development of advanced spintronic devices based on Pt and other heavy metals. [ABSTRACT FROM AUTHOR]

Normalized VSTE–H loops measured for generators fabricated from LPE‐grown yttrium iron garnet Y3–xBixFe5O12 (YIG/Bi:YIG) films agree well with the normalized M–H curves observed for those films by using a vibrating sample magnetometer. VSTE and M are the spin‐thermoelectric (STE) voltage and the YIG/Bi:YIG magnetization depending on an external field H, respectively. The coincidence between VSTE–H loops and M–H curves indicates that VSTE strongly depends on the magnetic property of ferrimagnetic insulator YIG films incorporated in STE generators. We try explaining the STE generation with VSTE–H loops from a viewpoint of domain magnetization processes in single‐crystal YIG/Bi:YIG films grown by liquid phase epitaxy (LPE). We exemplify that our idea about the fundamental mechanism of STE generation in an insulator‐based generator also well explains the mode of spin waves generated under a temperature gradient ∇T parallel to a plane of Pt/YIG bilayer interface. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Femtosecond laser‐induced photoexcitation of ferromagnet (FM)/heavy metal (HM) heterostructures has attracted attention by emitting broadband terahertz frequencies. The phenomenon relies on the formation of an ultrafast spin current, which is primarily attributed to the direct photoexcitation of the FM layer. However, during the process, the FM layer also experiences a secondary excitation led by the hot electrons from the HM layer that travel across the FM/HM interface and transfer additional energy in the FM. Thus, the generated secondary spins enhance the total spin current formation and lead to amplified spintronic terahertz emission. These results emphasize the significance of the secondary spin current, which even exceeds the primary spin currents when FM/HM heterostructures with thicker HM are used. An analytical model is developed to provide deeper insights into the microscopic processes within the individual layers, underlining the generalized ultrafast superdiffusive spin‐transport mechanism. [ABSTRACT FROM AUTHOR]

Aim: Minimally invasive surgery (MIS) has been introduced as an alternative to more radical surgical procedures. The Japan Society of Gynecologic and Obstetric Endoscopy and Minimally Invasive Therapy conducted a cross‐sectional questionnaire survey to ascertain the status of MIS for endometrial cancer. Methods: The survey was conducted between May 10 and June 30, 2022. The questionnaire included information on personal attributes, academic affiliations, qualifications, hysterectomies, and intraoperative procedures performed. Results: The total number of questionnaire respondents was 436 (9.2% of the membership). The hysterectomy methods and percentage performed were as follows: simple total hysterectomy (equivalent to benign surgery), 3%; simple total hysterectomy with care to avoid shaving the cervix, 31%; extended total hysterectomy, 48%; and modified radical hysterectomy, 15%. An analysis of hysterectomies performed using MIS for endometrial cancer by qualified gynecologists of endoscopy or board‐certified gynecologic oncologists showed a tendency not to choose simple total hysterectomy compared to the gynecologists who did not hold certification (p = 0.019, p = 0.045, and p = 0.010, respectively). Additionally, 67% of respondents did not use uterine manipulators, and 59% of the respondents did not perform lymph node dissection following the guidelines for treating endometrial cancer in Japan. Conclusion: This study provided the current status of MIS for endometrial cancer in Japan. The hysterectomy method, use of uterine manipulators, and criteria for omitting lymph node dissection were generally in agreement with the guidelines. Currently, an extra‐fascial simple hysterectomy, including at least not shaving the cervix, was a major method for early invasive endometrial cancer using MIS. [ABSTRACT FROM AUTHOR]

Interfacial two‐dimensional electron gases (2DEG), especially the SrTiO3‐based ones at the unexpected interface of insulators, have emerged to be promising candidates for efficient charge–spin interconversion. Herein, to gain insight into the mechanism of the charge–spin interconversion, quasi‐2DEG between insulating SrTiO3 and two types of aluminum‐based amorphous insulators, namely SrTiO3/AlN and SrTiO3/Al2O3, are focused on and their charge‐to‐spin conversion efficiency is estimated. The two types of amorphous insulators are selected to probe the overlooked contribution of oxygen vacancy. A mechanism to explain the results of spin–torque ferromagnetic resonance measurements is proposed and an analysis protocol to reliably estimate in quasi‐2DEG is developed. The resultant, thickness of the 2DEG, is estimated to be 0.244 and 0.101 nm−1 for SrTiO3/AlN and SrTiO3/Al2O3, respectively, which are strikingly comparable to their crystalline counterparts. Furthermore, a large direct current modulation of resonance linewidth in SrTiO3/AlN samples is developed, confirming and attesting an oxygen vacancy‐enabled charge–spin conversion. The findings emphasize the defects' contribution‐, especially in oxide‐based low‐dimensional systems, and provide a way to create and enhance charge–spin interconversion via defect engineering. [ABSTRACT FROM AUTHOR]