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91.
Franç ois Germinet Abel Klein 《Proceedings of the American Mathematical Society》2003,131(3):911-920
We study the decay at large distances of operator kernels of functions of generalized Schrödinger operators, a class of semibounded second order partial differential operators of mathematical physics, which includes the Schrödinger operator, the magnetic Schrödinger operator, and the classical wave operators (i.e., acoustic operator, Maxwell operator, and other second order partial differential operators associated with classical wave equations). We derive an improved Combes-Thomas estimate, obtaining an explicit lower bound on the rate of exponential decay of the operator kernel of the resolvent. We prove that for slowly decreasing smooth functions the operator kernels decay faster than any polynomial.
92.
David E. Edmunds Bohumí r Opic 《Proceedings of the American Mathematical Society》2003,131(3):745-754
We give new characterizations of Lorentz spaces by means of certain quasi-norms which are shown to be equivalent to the classical ones.
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Jin Tang Jialiang Jiang Ning Wang Yaodong Wu Yihao Wang Junbo Li Yona Soh Yimin Xiong Lingyao Kong Shouguo Wang Mingliang Tian Haifeng Du 《Advanced functional materials》2023,33(4):2207770
Magnetic skyrmions are localized particle-like nontrivial swirls that are promising in building high-performance topological spintronic devices. The read-out functions in skyrmionic devices require the translation of magnetic skyrmions to electrical signals. Here, combined real-space magnetic imaging and anisotropic magnetoresistance studies on dipolar skyrmions are reported. A single skyrmion chain and single skyrmion are observed using Lorentz transmission electron microscopy imaging. Meanwhile, the field, helicity, and skyrmion count dependence of anisotropic magnetoresistance of the Fe3Sn2 nanostructures are obtained simultaneously. These results demonstrate that the anisotropic magnetoresistance of skyrmions is independent of the helicity and proportional to the skyrmion count. This study promotes read-out operations in skyrmion-based spintronic devices. 相似文献
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Minmin Liu Zhengchen Wu Liting Yang Xiaowei Lv Ruixuan Zhang Huibin Zhang Xiangyu Wang Guanyu Chen Jincang Zhang Hualiang Lv Renchao Che 《Advanced functional materials》2023,33(48):2307943
The technological advances in wearable electronics and military stealth have spawned extensive research into electromagnetic wave absorbents. Despite the rapid progress in the geometrical modulation of magnetic absorbents, the engineering strategy of microwave-responsive magnetic domains is underdeveloped and the response dynamics remain unclear. Herein, a surface finite-sized atom reconstruction procedure is proposed to accurately modulate the local magnetic topological domains, dramatically enhancing the magnetic loss capacity. Due to the selectivity of atom reconstruction, vortex and stripe domains are controllably hybridized around the porous surface to broaden the interactive domain region, significantly intensifying energy absorption of the microwave field. Meanwhile, the amorphous/crystalline interfaces around atom reconstruction regions can induce interfacial polarization, enabling the optimization of dielectric loss capacity. Therefore, a satisfactory magnetic–dielectric synergy is realized to demonstrate the strong absorption intensity of −31.2 dB and the broad absorption bandwidth of 5.9 GHz. Furthermore, the surface-based magnetic domain transformation and microwave energy attenuation mechanisms are thoroughly revealed to break the black box of structure–function through electron holography and micromagnetic simulation. These achievements demonstrate a promising solution to improve high-frequency magnetic properties and provide a feasible route to interpret the structure-relevant magnetic loss capacity. 相似文献
98.
郭健 《电气电子教学学报》2011,33(2):110-112
本文采用有限元方法对三相交流电机内部磁场的实际运动情况进行了模拟仿真,仿真结果很好地展示了电机磁场正反转的实现方法、不同极对致电机的磁场分布以及磁场旋转速度与极对数之间的关系.分析结果在教学中的应用可对学生掌握和熟悉电工学课程中三相交流电机内部磁场分布、正反转实现以及磁场旋转速度有一定的帮助. 相似文献
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