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Interconversion between charge and spin through spin-orbit coupling at a heavy metal (HM)/ferromagnet (FM) interface plays a key role in determining the amplitude of spin Hall magnetoresistance (SMR), which might maximally facilitate its applications in novel electronics. In this study, annealed NiFe films grown on MgO (100) substrates capped with Pt and Ta are reported to exhibit a maximum SMR. When the measuring temperature is reduced, the SMR rises and is significantly larger in crystalline NiFe than in amorphous NiFe. Another physical process for the negative SMR in Ta(

Magnetic skyrmions have the potential for a wide range of applications in the next generation of spintronics since they are topologically protected spin configurations in the nanometer length scale. In order to be used in the logic gate, it is necessary to consider how to manipulate magnetic skyrmions. At present, the current drive is the mainstream drive, but this method could consume enormous energy for large Joule heating. In this work, the potential well is introduced to drive skyrmion to reduce energy consumption. The potential well is generated by voltage-controlled magnetic anisotropy (VCMA). We study the possibility of the potential well induced skyrmion movement within a certain distance, the relevant factors that affect the distance of skyrmion induction and propose a switched-voltage driving structure within the well-established framework of micromagnetics. Its processes have been theoretically investigated and demonstrated, in which the switched-voltage driving structure can be used to drive skyrmions. Our results provide guidance for the design of low energy consumption voltage-driven skyrmion driving method and a new concept for track memory.

The three-dimensional physical models for FeNi/Cu/FeNi films with two different types of structures which are linear and meander are developed. The relationship between the impedance of the films and the applied magnetic field or excitation frequency is obtained and the influence of geometric parameters and structures of the films on the giant magnetoimpedance (GMI) effect is analyzed. The result shows that the GMI effect in the film with a horizontal meander structure appears to be much stronger compared with that in a linear structure. The negative mutual inductance of the meander FeNi/Cu/FeNi films reduces the total inductance and decreases frequency response. Meanwhile, the GMI effect and the negative mutual inductance are enhanced by increasing the number of turns or decreasing the space width between each segment. Based on these effects, the FeNi/Cu/FeNi film with a vertical meander structure is proposed and simulated, which reflects the design of the meander structure in the thickness direction. The distance between each segment is reduced to 500 nm. The GMI effect and the negative mutual inductance are greatly enhanced (the maximum value of the GMI ratio increases from 207% to 1247% when the excitation frequency changes from 50MHz to 300MHz). Furthermore, the spatial resolution of the film is further improved. The results obtained could be useful both for a better understanding of the GMI effect of the FeNi/Cu/FeNi film with a meander structure and for providing a choice for the device preparation of highly sensitive magnetic sensors.

We analyze the coupling between an adjacent field ring and coupling ring of the two-dimensional optical resonator array to obtain topological edge state. Using finite-difference time-domain method, the energy band structure, light field distribution and transmission spectrum are simulated to investigate the optimised coupling parameters under the topological boundary state. When the coupling coefficient is approximately 0.775, the system can form a topological state in the wavelength of 1.55 μm-1.56 μm while output can maintain a flat spectral response with normalized power above 0.9. The research in this paper will provide a basis for the potential application of topological edge states of tow-dimensional coupled resonant optical waveguide in the field of photonic communication.

Laryngeal cancer is detected commonly worldwide, and it ranks second highest in incidence among the respiratory tract neoplasms following only head and neck squamous cell cancer. In the present study salicin dimethyl ether was synthesized and evaluated against laryngeal cancers cells for anticancer property. MTT assay was used for the measurement of changes in TU686 and Tu212 cell proliferation while as induced apoptosis was detected by flow cytometry. Protein expression was determined by western blotting and expression of mRNA by RT-PCR assay. In the present study salicin dimethyl ether was synthesized by the reaction of salicin with methyl iodide using sodium hydride as base. Salicin dimethyl ether treatment led to a significant decrease in TU686 and Tu212 cell proliferation in a dose-dependent manner. In TU686 and Tu212 cells salicin dimethyl ether treatment caused a significant increase in cell apoptosis and elevated caspase-3 activity. Treatment with salicin dimethyl ether led to a prominent reduction in Bcl-2 protein expression in TU686 and Tu212 cells at 72 h. Salicin dimethyl ether treatment led to a prominent decrease in p-PI3K and p-Akt protein expression in TU686 and Tu212 cells, compared to the untreated cells. A significant increase in miR‑15a expression in TU686 and Tu212 cells was observed on treatment with salicin dimethyl ether at 72 h. In summary, the current study demonstrates that salicin dimethyl ether, a synthetic derivative of salicin, suppresses proliferation of TU686 and Tu212 cells. The underlying mechanism involves induction of apoptosis, inhibition of PI3K/Akt pathway and promotion of miR-15a expression. Therefore, salicin dimethyl ether may be used for inhibition of laryngeal cancer growth, however, in vivo studies need to be conducted to confirm the effect.

Laryngeal squamous cell carcinoma (LSCC) is one of the most common forms of head and neck cancers. However, few studies have focused on the correlation between competing endogenous RNA (ceRNAs) and immune cells in LSCC.RNAseq expression of LSCC and adjacent tissues were downloaded from The Cancer Genome Atlas to establish a ceRNA network. The key gene in ceRNA was screened by the cox regression analysis to establish a prognostic risk assessment model. The CIBERSORT algorithm was then used to screen important tumor-infiltrating cells related to LSCC. Finally, co-expression analysis was applied to explore the relationship between key genes in the ceRNA network and tumor-infiltrating cells. The external datasets were used to validate critical biomarkers.We constructed a prognostic risk assessment model of key genes in the ceRNA network. As it turned out, Kaplan-Meier survival analysis showed significant differences in overall survival rates between high-risk and low-risk groups (P.001). The survival rate of the high-risk group was drastically lower than that of the low-risk group, and the AUC of 1 year, 3 years, and 5 years were all above 0.7. In addition, some immune infiltrating cells were also found to be related to LSCC. In the co-expression analysis, there is a negative correlation between plasma cells and TUBB3 (r = -0.33, P = .0013). External dataset validation also supports this result.In this study, we found that some key genes (SLC35C1, CLDN23, HOXB7, STC2, TMEM158, TNFRSF4, TUBB3) and immune cells (plasma cells) may correspond to the prognosis of LSCC.

In order to maintain the thermal stability of SOT devices with nanoscale size, it is desirable to achieve current induced magnetic switching in magnetic materials with high perpendicular anisotropy. In the present paper, current induced field-free switching of FePt/[TiN/NiFe]5 is achieved by interlayer exchange coupling, in which in-plane magnetized NiFe serves as a coupling layer through a TiN space layer. The large Ku (1.03 × 107 erg cc−1) and low critical current density values (0.17 × 107 A cm−2) show great advantages in thermal stability and energy consumption. Interestingly, it is found that the rotation directions of the current-induced magnetic switching loops under different applied magnetic fields are dependent on the sputtering temperature of [TiN/NiFe]5 multilayers: once sign change for FePt/[TiN/NiFe]5 RT and three sign changes for FePt/[TiN/NiFe]5 HT. Simultaneously, when the magnetization direction of NiFe changes from the Hx direction to −Hx direction, the switching polarities at Hx = 0 always remain unchanged, which is different from other groups’ reports. These phenomena may be attributed to the combined effect of TiN layer thickness induced ferromagnetic or antiferromagnetic coupling and the inherent Hin. Furthermore, gradual tuning of resistance states through the trains of current pulses has also been realized, showing potential applications in artificial synaptic networks. These results will put forward the applications of L10-FePt in current controlled MRAM and neuromorphic computing.

Van der Waals antiferromagnets (AFMs) provide a two-dimensional (2D) platform for spintronic devices with exceptional properties. However, the electric transport features of the magnetic order of van der Waals AFM influenced by different field directions and amplitudes has not been demonstrated systematically. In this letter, we investigate the magnetic texture of the exfoliated van der Waals FePS3, a uniaxial AFM with perpendicular anisotropy, detected by the spin Hall magnetoresistance (SMR). Magnetic field- and temperature- dependent longitudinal magnetoresistance measurements in three orthogonal directions for the exfoliated FePS3/Pt nanostructures are conducted. The modulations in the SMR signal enable the separation of two contributions to the SMR, one of which corresponds to the negative signature of AFM SMR caused by in-plane field rotations, and the other of which is caused by canted spins in perpendicular AFM order. Our findings offer great guidance for further research and investigation using SMR approach of the magnetic texture in van der Waals AFMs.

We use a periodic microring resonator array (MRRA) to realize photonic topological insulator. By tuning the coupling of resonators, two topological edge states can be observed in different bands in the dispersive band, normalized transmission spectrum and light field distribution. From the dispersion band structure, we calculate the group velocity, group velocity dispersion, normalized delay bandwidth product and other delay properties. It is demonstrated that optical delay lines (ODLs) in topological MRRA not only can obtain a comparable delay times, but also show a flatter transmission spectrum and more stable delay time, compared with the traditional coupled resonator optical waveguide. Our work may provide a theoretical reference for the topological ODLs with robust transmission.

To study the substitutability of noble metal electrodes in memristors, the effect of Pt/HfO2/Ti structure on the replacement of noble metal electrode Pt by different electrodes was studied. Compared with the unsubstituted devices, the HfO2-based RRAM devices with TiN and TiOxNy electrodes devices showed good resistive switching performance and resistive switching mechanism under oxygen ion migration. Five devices were prepared, and their resistive switching mechanism under oxygen ion migration was investigated. Moreover, besides the resistive switching phenomenon of these RRAM devices, it was found that significant rectifying characteristics were exhibited in a highresistance state (HRS). This phenomenon can be explained by regulation of the Schottky barrier of the interface between the top electrode and the resistive layer, which can be influenced by the migration of oxygen vacancies.

To improve the resistive switching performance of RRAM devices, it is desirable to find electrodes with good ability of oxygen reservoir. In this paper, bipolar switching mode of TiN/SiO2/FePt devices is achieved by using FePt as oxygen reservoir, since O atoms will be absorbed by Fe atoms to form FeOx film. Therefore, the oxygen reservoir’s ability can be evaluated by the molar ratio of FeOx in FePt film and it is found that the more molar ratio of FeOx the stronger oxygen reservoir’s ability is obtained. Interestingly, the self-rectifying characteristics in the devices with FePt electrode is observed due to the different work functions between TiN (4.7 eV) and FePt (> 5 eV). Furthermore, the transition between self-rectifying mode and diode mode can be achieved by controlling the applied voltage, which is beneficial for 1D1R architecture. The study in this paper may offer a method for fabrication of oxide-RRAM based 3D crossbar array with good performances.

A new type of weak signal detection system that combines the memristor and Van der pol-Duffing chaotic system has been proposed in this paper, and the dynamic characteristics of the system are studied. It is observed that the system can change from a chaotic state to a periodic state under different driving force amplitudes. Moreover, as compared with several classical chaotic oscillators, the numerical simulation results show that the system has stronger anti-noise performance with the detectable signal-to-noise ratio reaches -163dB, and has a wider detection range. Its detection accuracy is up to 1 × 10 −9 . More importantly, this paper provides the circuit implementation scheme of the system, and the weak signal can be detected with our designed circuit. This may offer a possible way for weak signal detection system with good performance in anti-noise performance, detection range and accuracy.

This study investigated the impact of electrode materials on HfO₂-based RRAM devices. The research includes three types of electrode materials: (1) the electrodes with strong ability of oxygen reservoirs; (2) the electrode with poor ability of oxygen reservoirs; (3) the active electrode with injection ability. Through implementing different combinations of electrodes, three types of switching modes were obtained and the relative conduction mechanism was analyzed, as well as conduction model. Those studies may offer ways of using electrodes to control the resistive switching processes and fabricating the RRAM devices with good performance.

Introduction Laryngeal cancer is the most common head and neck cancer worldwide. It is urgent to identify the mechanisms underlying laryngeal cancer pathogenesis. In the present study, we investigated the biological functions of Peripherin 2 (PRPH2) in laryngeal cancer and uncovered the molecular mechanism underlying this disease. Methods Laryngeal cancer tissues were used to analyze the expression of PRPH2. In vitro transwell matrigel invasion assay and annexin V anoikis assay in laryngeal cancer cells were conducted to investigate PRPH2 related biological functions. Quantitative real-time PCR and Western blotting were performed to investigate the expression and mechanism of PRPH2 in laryngeal cancer. Results We found that the expression of PRPH2 was significantly downregulated in laryngeal cancer tissues. Overexpression of PRPH2 suppressed the invasion and anoikis inhibition of laryngeal cancer cells. Furthermore, PRPH2 overexpression increased the phosphorylation of YAP and LATS1 and decreased the activities of Rho GTPases, while PRPH2 knockdown had opposite effects. Inhibitors of the Hippo pathway abrogated PRPH2 knockdown-induced laryngeal cancer cell invasion and anoikis inhibition. Discussion These results suggested that PRPH2 suppresses laryngeal cancer cell invasion and anoikis inhibition by activating Hippo signalling. PRPH2 may serve as a potential therapeutic target for laryngeal cancer in the future.

In order to improve the resistive switching performance of SiO2-based resistance random access memory (RRAM) devices, the evolution from pure oxide-based devices to metallic nanoparticle dispersed oxide-based devices is investigated in this paper. It is found that a high ratio of dispersed-oxide/pure-oxide and thin SiO2 film can increase the uniformity and endurance of RRAM devices. Pure TiN/SiO2/Au RRAM devices show large distributions and poor endurance for repeated resistive switching process, while the TiN/SiO2:FePt/SiO2/Au RRAM devices exhibit higher uniformity and better endurance. Moreover, the fluctuations and degradation of high-resistance state and low-resistance state are observed in the former devices; by increasing the ratio of dispersed-oxide/pure-oxide in TiN/SiO2/SiO2:FePt/SiO2/Au, high consistency resistive switching is obtained. It is believed that the random formation of conducting filaments (CFs) causes poor performance of RRAM devices, and with a higher ratio of dispersed-oxide/pure-oxide the morphology of CFs is controlled due to the local field enhancement. The results in this paper may provide a method of fabricating high-performance RRAM devices for industry application.

The resolution of giant magneto-impedance (GMI)-based magnetic sensor is limited by its equivalent magnetic noise level. It presents a white noise and a low-frequency 1/ f noise behavior. Previous works have showed that the white noise is mainly determined by the electronic conditioning noise, nevertheless, the 1/ f noise’s origin is not totally clear yet. To optimize the 1/ f noise, in this paper, first, we develop an optimized negative feedback GMI sensor. It contains of a low-distortion oscillator, a high-performance amplitude detector, and a GMI sensing element with adjustable static working point. And then, the sensitivity and the 1/ f noise level of the GMI sensor are studied when considering the electronic conditioning parameters and the static working point. The experiment results show that the adjustment of the static working point has a significant effect on the 1/ f noise at low frequencies. The optimal 1/ f noise is obtained by setting the static working point at the position where the GMI element possesses with the maximum intrinsic sensitivity. Finally, we achieve the GMI sensor noise performance of 20 pT/ $\surd $ Hz at white noise region and 100 pT/ $\surd $ Hz at 1 Hz.

In order to maintain the thermal stability of SOT devices with nanoscale size, it is desirable to achieve current induced magnetic switching in magnetic materials with high perpendicular anisotropy. In the present paper, current induced field-free switching of FePt/[TiN/NiFe]

Laryngeal cancer is detected commonly worldwide, and it ranks second highest in incidence among the respiratory tract neoplasms following only head and neck squamous cell cancer. In the present study salicin dimethyl ether was synthesized and evaluated against laryngeal cancers cells for anticancer property. MTT assay was used for the measurement of changes in TU686 and Tu212 cell proliferation while as induced apoptosis was detected by flow cytometry. Protein expression was determined by western blotting and expression of mRNA by RT-PCR assay. In the present study salicin dimethyl ether was synthesized by the reaction of salicin with methyl iodide using sodium hydride as base. Salicin dimethyl ether treatment led to a significant decrease in TU686 and Tu212 cell proliferation in a dose-dependent manner. In TU686 and Tu212 cells salicin dimethyl ether treatment caused a significant increase in cell apoptosis and elevated caspase-3 activity. Treatment with salicin dimethyl ether led to a prominent reduction in Bcl-2 protein expression in TU686 and Tu212 cells at 72 h. Salicin dimethyl ether treatment led to a prominent decrease in p-PI3K and p-Akt protein expression in TU686 and Tu212 cells, compared to the untreated cells. A significant increase in miR‑15a expression in TU686 and Tu212 cells was observed on treatment with salicin dimethyl ether at 72 h. In summary, the current study demonstrates that salicin dimethyl ether, a synthetic derivative of salicin, suppresses proliferation of TU686 and Tu212 cells. The underlying mechanism involves induction of apoptosis, inhibition of PI3K/Akt pathway and promotion of miR-15a expression. Therefore, salicin dimethyl ether may be used for inhibition of laryngeal cancer growth, however, in vivo studies need to be conducted to confirm the effect.

Nowadays, in the field of magnetic detection, the combination of magnetic sensors and multirotor unmanned aerial vehicle (UAV) is more and more widely used. Multirotor UAV has certain requirements for the volume and sensitivity of the sensor. For the detection of weak magnetic field signals at single frequency point, the sensitivity, accuracy, and volume of the inductive magnetic sensors still have a large room to improve. Based on theoretical analysis and simulation, this paper added a cylindrical high permeability sheet on both sides of the magnetic core in this paper to improve the sensitivity of the sensor. The advantage of this method is that it will not increase the volume and weight of the sensor while greatly improving the sensitivity; Meanwhile, through the analysis of the crosstalk between the cores of the triaxial inductive magnetic sensor, an applicable spacing is obtained among the triaxial coils, so that the crosstalk voltage is under the resolution of the induction coil, the crosstalk effect can be ignored. The initial sensitivity of the induction coil designed in this paper can reach 0.20mV/nT@380Hz. The maximum equivalent magnetic crosstalk is about 6.45pT, which is suitable for the application of single frequency array magnetic measurement.

Aiming at the deficiencies of the existing chaotic detection methods, a new weak signal detection method based on chaotic synchronization system is proposed in this paper. This detection system is achieved by a memristor-based Duffing-Van der pol chaotic system, and the drive-response method is used to construct a synchronization system. By analyzing the synchronization error of the detection system, the amplitude estimate method of the test signal is proposed. This method only needs the chaotic system run in the chaotic state and avoids solving the running state. It can effectively solve the problems of complex parameter setting, long state transition time and difficulty in state determination in traditional detection methods. Experimental results indicate that this new method can effectively estimate the parameter information of the test signal.

The performance of TiN/HfO2/Ag resistive random-access memory (RRAM) devices combining the oxygen-based RRAM (OxRRAM) and conducting bridge random-access memory (CBRAM) was studied. Current compliance (CC) values could significantly affect the resistive switching process: with unidirectional CC, permanent breakdown for the devices was observed. With bidirectional smaller CC, the stable bipolar resistive switching mode was obtained, and the cation injection played a leading role in the resistive switching process, while the devices with higher CC always remained in low-resistance state (LRS). The resistance–voltage (R–V) curve and conducting mechanism were analyzed for the bidirectional smaller CC devices, indicating ohmic conduction for the LRS, while the space charge limited the current for the high-resistance state. The results of x-ray photoelectron spectroscopy showed that oxygen vacancies participated in the resistive switching process. It could be concluded that conducting paths were formed from conducting filaments of oxygen vacancies and conducting bridges of Ag grains, and the different formation rate of conducting filaments related to the values of CC was the prime reason for the various changes. Moreover, the characteristics of TiN/HfO2/Ta devices proved the universality of bidirectional CC. The method of making the OxRRAM and CBRAM coexist in the RRAM devices may offer a way to fabricate devices with low power consumption.

For real-world applications, it is desirable to realize field-free spin–orbit torque (SOT) switching in thin films with high perpendicular magnetic anisotropy (PMA). In this paper, we report that field-free SOT switching in a L10-FePt single layer with a large switching ratio of 26% is obtained by using a MgO ⟨100⟩⋀8°/⟨100⟩ miscut substrate. It is found that field-free switching depends on the direction of the imposed pulse current. Only when the electric current is along the y (010)-direction but not along the x (100)-direction does field-free switching happen, which can be attributed to the tilted PMA induced symmetry breaking in the x–z plane. Furthermore, under the field-free condition, our FePt single layer system exhibits stable multi-state magnetic switching behavior and nonlinear synaptic characteristics. This work paves the way to realize field-free SOT switching in the L10-FePt single layer, which will have significant impact on spin memory devices and synaptic electronics.

The stress-induced magnetic anisotropy can significantly affect giant magneto-impedance (GMI) effect of the soft magnetic film. This paper is devoted to the GMI effect of the single layer soft magnetic film implied without and with a stress. By simulating a physical model with MATLAB and COMSOL software, the impedance expression of the single layer soft magnetic film and the relation between external magnetic field and magnetic permeability are deduced. We observed that, without a stress, the sensitive region increased firstly and then decreased with the increasing of the excitation current frequency from 1 MHz to 200 MHz. While the film was subjected to the stress in the direction of the current with one end stressed, the stress on the film was gradually reduced from stressed end to free end. Also, the impedance change rate of the film changed when the stress was added, which is similar to the effect of adding a bias magnetic field on the film. More importantly, the addition of stress σ can induce the bias of the GMI measurement range and improve its sensitivity near zero magnetic fields. This may provide a new way for designing a GMI sensor with higher sensitivity and adjustable measurement range.

We propose and analyse a novel optical pressure sensor based on series-coupled double microring resonators (SDMRRs) on a simple beam. The pressure applied on the sensor is measured through the chan...

Slope monitoring is an effective way to prevent engineering accidents. Although existing methods have the strength of high accuracy, the time-consuming and high-cost problems are also accompanied. For some preliminary measurements of slope detection with lower accuracy requirements, existing detection methods are expensive. Therefore, a low-cost slope monitoring method based on wireless image transmission technology is proposed in this paper. This method combines GPRS technology with image compression technology which has the advantages of low cost and not being restricted by terrain conditions. Also, the site condition of the slope project can be accurately reflected by the image transmitted to the terminal.

Reports on the influence of the stress on giant magnetoimpedance (GMI) effect of CoFeSiB films are rarely seen. Therefore, the influence of stress on the GMI effect of CoFeSiB thin-film was studied in this investigation. Firstly, to select suitable substrates for applying stress, CoFeSiB films were fabricated on different flexible substrates with magnetron sputtering, and the hysteresis loops of the films were measured. The results show that the magnetic properties of the films on polyester (PET) substrates and silicate flexible glass are similar and better than polyimide (PI). So they are candidate materials for flexible substrates. And then, the GMI curves of the films under different stresses were measured. The results show that applying longitudinal tensile stress would reduce the longitudinal anisotropy and weaken the GMI effect of the CoFeSiB film. The research on the influence of stress on GMI thin-film would be helpful to fabricate flexible GMI sensors of stable performance.

The accurate detection of the weak magnetic signal has important applications in many fields, and lock-in amplifiers are often used in them. However, commercial lockin amplifiers are expensive and bulky, and are not suitable for use in field environments such as the magnetic exploration. In this paper, a weak magnetic signal detection system is designed based on a portable lock-in amplifier, which is used to solve the problem. The system takes the portable lock-in amplifier circuit as its core, and contains a fluxgate sensor. Combined with A/D acquisition and LabVIEW, the system achieves the real-time display of measurement data on the laptop. Experimental results show that the correlation coefficient of input and output of the system is up to 0.998 under the noise environment. The system achieves the effective measurement of the amplitude of the weak alternating magnetic field signal when the interference magnetic fields are complex. The detection system has the characteristics of high resolution, good linearity and portability, and has good potential for field applications.