Phase control of spin waves in the van der Waals antiferromagnet NiPS3

We demonstrate phase control of magnons in the van der Waals antiferromagnet NiPS3 using optical excitation by polarized light. The sign of the coherent precession of spin amplitude changes upon (i) reversing the helicity of a circularly polarized pump beam, or (ii) rotating the polarization of a linearly polarized pump by π/2. Because these two excitation pathways have comparable generation efficiency, the phase of spin precession can be continuously tuned from 0 to 2π by controlling the polarization state of the pump pulse. The ability to excite magnons with a desired phase has potential applications in the design of a spin-wave phased array and ultrafast spin information processing

Phase control of magnons in the van der Waals antiferromagnet NiPS3_3

We demonstrate phase control of magnons in the van der Waals antiferromagnet NiPS$_3$ using optical excitation by polarized light. The sign of the coherent precession of spin amplitude changes upon (1) reversing the helicity of a circularly polarized pump beam, or (2) rotating the polarization of a linearly polarized pump by $\pi/2$. Because these two excitation pathways have comparable generation efficiency, the phase of spin precession can be continuously tuned from 0 to $2\pi$ by controlling the polarization state of the pump pulse. The ability to excite magnons with a desired phase has potential applications in the design of a spin-wave phased array and ultrafast spin information processing

Nonreciprocal second harmonic generation in a magnetoelectric material

Nonreciprocal devices that allow the light propagation in only one direction are indispensable in photonic circuits and emerging quantum technologies. Contemporary optical isolators and circulators, however, require large size or strong magnetic fields because of the general weakness of magnetic light-matter interactions, which hinders their integration into photonic circuits. Aiming at stronger magneto-optical couplings, a promising approach is to utilize nonlinear optical processes. Here, we demonstrate nonreciprocal magnetoelectric second harmonic generation (SHG) in CuB2O4. SHG transmission changes by almost 100% in a magnetic-field reversal of just 10 mT. The observed nonreciprocity results from an interference between the magnetic-dipole- and electric-dipole-type SHG. Even though the former is usually notoriously smaller than the latter, it is found that a resonantly enhanced magnetic-dipole-transition has a comparable amplitude as non-resonant electric-dipole-transition, leading to the near-perfect nonreciprocity. This mechanism could form one of the fundamental bases of nonreciprocity in multiferroics, which is transferable to a plethora of magnetoelectric systems to realize future nonreciprocal and nonlinear-optical devices.Comment: 21 pages, 4 figure

マルチフェロイックCuB2O4における非相反光学現象

学位の種別: 課程博士審査委員会委員 : （主査）東京大学教授 有馬 孝尚, 東京大学准教授 貴田 徳明, 東京大学教授 求 幸年, 東京大学准教授 徳永 将史, 東京大学准教授 原田 慈久University of Tokyo(東京大学

Clinical outcomes of first-line combination therapy with immune checkpoint inhibitor for metastatic non-clear cell renal cell carcinoma: a multi-institutional retrospective study in Japan

The version of record of this article, first published in International Journal of Clinical Oncology, is available online at Publisher’s website: https://doi.org/10.1007/s10147-024-02612-1.Background: In metastatic clear cell renal cell carcinoma (ccRCC), recent studies have shown promising efficacy of immune checkpoint inhibitor (ICI) combination therapy. However, there are insufficient evidences about clinical efficacy and safety of ICI combination therapy in metastatic non-ccRCC (nccRCC). Methods: We retrospectively investigated 44 patients treated with nivolumab plus ipilimumab (ICI + ICI group) or anti-PD-1/PD-L1 inhibitor plus tyrosine kinase inhibitors (TKI) (ICI + TKI group), and assessed clinical efficacy in both groups. Results: Of all patients, overall response rate and disease control rate for ICI combination treatments were 36.3% and 75%, respectively. The median progression-free survival (PFS) and overall survival (OS) was 8.8 and 23.9 months, respectively. Multivariate analysis revealed that the presence of liver metastasis significantly affected worse PFS and OS (p = 0.035 and p = 0.049). Importantly, PFS and OS seemed similar in ICI + ICI group and ICI + TKI group (p = 0.778 and p = 0.559). Although the discontinuation rate of the combination therapy due to adverse effects in patients aged ≥ 75 years was significantly higher compared to that in patients aged < 75 years (45% versus 12%, p = 0.017), there were no significant differences in PFS and OS between two groups (p = 0.290 and p = 0.257, respectively). Conclusion: This study confirms clinical benefit of ICI combination therapy for metastatic nccRCC patients in real-world settings. Furthermore, the effectiveness of combination therapy was comparable between patients aged < 75 and those ≥75 years with respect to clinical prognosis

Treatment responses and their predictors in patients with rheumatoid arthritis treated with biological agents

Biological agents represent an important advancement in for the treatment of rheumatoid arthritis (RA), but there is a subset of patients who do not improve despite therapy. This study aimed to determine the efficacy of biological agents for RA and to identify clinical factors that are associated with their response. We studied 98 patients with RA who started an initiating biological agent which was selected from infliximab, etanercept, adalimumab and tociliximab at 4 medical institutions. Etanercept was the most frequently used biological agent followed by infliximab although there was a difference in the selection of the biological agents among medical institutions. We found that etanercept achieved the highest treatment response, remission rate and drug survival rate. A high disease activity in the baseline disease activity score-c-reactive protein (CRP) was shown to be a negative predictor of the treatment response, and high patient global assessment was significantly less likely to achieve a good response. At week 4, decreases in 28 swollen joint counts and CRP were useful as predictors for sustaining the efficacy up to week 48. These data demonstrate that assessments of the disease activity at baseline and the early treatment response may be useful in predicting the efficacy and drug survival rate of biological agents

平成29年度「卒業研究」実践報告

今年度の卒業研究はテーマ設定に関する時間を確保するために、2年次の「T-GAP」の内容に卒業研究の内容を含めて実施した。評価に関しては国際バカロレアの「課題論文」(EE)を参考にしつつ、生徒の実態に沿う形で評価規準を作り直して使用した。テーマ設定に時間をかけたころとなどにより、多くの先行研究を参考にし、主体的に課題を設定して卒業研究に取り組む姿が確認された