Direct imaging of a zero-field target skyrmion and its polarity switch in a chiral magnetic nanodisk

A target skyrmion is a flux-closed spin texture that has two-fold degeneracy and is promising as a binary state in next generation universal memories. Although its formation in nanopatterned chiral magnets has been predicted, its observation has remained challenging. Here, we use off-axis electron holography to record images of target skyrmions in a 160-nm-diameter nanodisk of the chiral magnet FeGe. We compare experimental measurements with numerical simulations, demonstrate switching between two stable degenerate target skyrmion ground states that have opposite polarities and rotation senses and discuss the observed switching mechanism.Comment: 18 pages, 4 figure

The construction of curriculum learning pattern of master of education: theoretical foundation and practical framework

The implementation and operation of the “Curriculum for Education” is an important medium and carrier for nurturing the in-depth learning literacy of postgraduates, especially the implementation and operation of the principle courses provide an important platform and guarantee for cultivating the principle thinking of M.Ed. Combined with the analysis of research data, this paper finds that (1) the learning pattern of M.Ed. courses has the characteristics and practical characteristics of openness, initiative and self-adaptability. (2) The practical framework for constructing the learning pattern of the M.Ed. programme consists of two modules that lay out progressive learning tasks that point to “academic competence in the curriculum” and “practical competence in teaching”. (3) Guiding M.Ed. students to participate in course evaluation and promoting the formation of M.Ed. learning experiences are the core mechanisms of M.Ed. course learning patterns in practice

A 5.8 GHz DSRC Digitally Controlled CMOS RF-SoC Transceiver for China ETC

This paper presents a 5.8 GHz dedicated short range communication (DSRC) CMOS RF-SoC transceiver with digitally controlled RF architecture for China electronic toll collection (ETC) system. The operation of key RF blocks, such as ASK modulator, power amplifier, LNA, and mixer, are directly controlled by digital baseband. Compared with state-of-the-art designs in literature, this work demonstrates remarkable advantages in design simplicity, Tx output peak power, adjacent channel power ratio (ACPR), dynamic range, occupied bandwidth (OBW), bit error rate (BER), and so on