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Two-dimensional (2D) materials exhibit fascinating and outstanding optoelectronic properties, laying the foundation for the development of novel optoelectronic devices. However, ultra-weak light absorption of 2D materials limits the performance of the optoelectronic devices. Here, a structure of MoS2/graphene/Au integrated onto the side-polished fiber (SPF) is proposed to achieve a high-performance fiber-integrated multifunction-in-one optoelectronic device. It is found that the device can absorb the transverse magnetic (TM) mode guided in the SPF and generate photocurrents as a polarization-sensitive photodetector, while the transverse electric (TE) mode passes with low loss through the device, making the device simultaneously a polarizer. In the device, the MoS2 film and the Au finger electrode can enhance the TM absorption by 1.75 times and 24.8 times, respectively, thus allowing to achieve high performance: a high photoresponsivity of 2.2 × 105 A/W at 1550 nm; the external quantum efficiency (EQE) of 1.76 × 107%; a high photocurrent polarization ratio of 0.686 and a polarization efficiency of 3.9 dB/mm at C-band. The integration of 2D materials on SPF paves the way to enhance the light–2D material interaction and achieve high performance multifunction-in-one fiber-integrated optoelectronic devices.

Graphene has been widely used in photodetectors; however its photoresponsivity is limited due to the intrinsic low absorption of graphene. To enhance the graphene absorption, a waveguide structure with an extended interaction length and plasmonic resonance with light field enhancement are often employed. However, the operation bandwidth is narrowed when this happens. Here, a novel graphene-based all-fiber photodetector (AFPD) was demonstrated with ultrahigh responsivity over a full near-infrared band. The AFPD benefits from the gold-enhanced absorption when an interdigitated Au electrode is fabricated onto a Graphene-PMMA film covered over a side-polished fiber (SFP). Interestingly, the AFPD shows a photoresponsivity of >1 × 104 A/W and an external quantum efficiency of >4.6 × 106% over a broadband region of 980–1620 nm. The proposed device provides a simple, low-cost, efficient, and robust way to detect optical fiber signals with intriguing capabilities in terms of distributed photodetection and on-line power monitoring, which is highly desirable for a fiber-optic communication system.

This paper develops an active magnetic near field probe (H‐field probe) by using a four‐layer printed circuit board (PCB) technique. Two‐turn detection structure and a low noise amplifier are used to improve probe's frequency response. The two‐turn detection structure can maximize the use of PCB stack resources, and a 14.5 dB gain amplifier can increase signal output capability. The probe can then be used for electromagnetic compatibility (EMC) test from 150 kHz to 3 GHz. Compared with traditional active shielded‐loop H‐field probe (TAHP) with loop area of 500 μm2, the frequency response of the proposed probe can improve 20 dB at 0.5 GHz. Different from the method of comparing the sensitivity of the probe only through the frequency response, this paper measures and analyzes the real sensitivity of the probing device composed of the proposed probe. Under the condition of the same receiver parameter setting, the sensitivity at 0.5 GHz is increased by 11.7 dB compared with commercial passive probing device and 20.2 dB at 0.5 GHz compared with the probing device with TAHP device. It reaches −32.4 dB μA. In addition, the proposed probe has acceptable spatial resolution of 1.28 mm at 1 GHz, which is more suitable for printed circuit board level EMI analysis.

In this work, majority carrier tunneling current in Ferroelectric tunnel junction (FTJ) with bilayer composite barrier is simulated theoretically by using finite difference method and Wentzel–Kramers–Brillouin (WKB) method. The simulation results reveal that the metal/Al 2 O 3 /HZO/Si FTJ has a significant enhanced tunneling electroresistance (TER) effect as compared to traditional FTJ, and are also consistent with others’ experimental results.

A high-performance humidity sensor based on a side-polished single-mode fibre (SPF) coated with graphene oxide film was fabricated with a wheel side-polishing technique and spontaneous evaporation. The wavelength-selective coupling gave rise to a loss dip in the transmitted spectrum when a phase match condition was satisfied at a given resonant wavelength. The swelling effect of GO under high RH, which was confirmed by XRD and a spectroscopic ellipsometer, could increase the GO film thickness and led to a redshift at resonant wavelength. Experimental results show that the GO-film-coated SPF (GFC-SPF) is capable of working in two modes: tracing-wavelength mode and intensity variation mode. For the two working modes, the GFC-SPF has high sensitivity, good reversibility, good repeatability and excellent linearity. For the tracing-wavelength mode, a very high sensitivity of 0.145 nm/RH% and a high linear correlation of 99.6% were achieved in a low RH range of 32%–85%, while an ultrahigh sensitivity of 0.915 nm/RH% and a linear correlation of 98.7% were achieved in a high RH range of 85%–97.6%. For the intensity variation mode, a high sensitivity of 0.427 dB/RH% and an excellent linearity correlation of 99.8% were achieved in a wide RH range of 58.2%–92.5%. Such a high performance allows GFC-SPF to have widespread potential applications, such as in the fields of biology, chemical processing and food processing.

With the ever-increasing operating frequency in integrated circuit, it is very essentialto assess the radiation used to help the IC designer. Based on the similarity of electromagnetic patterns obtained from the radiation of ICs and their nonlinear edge, we develop a post-processing technique to group the electromagnetic patterns. A near field scanning is performed to obtain and extract the electromagnetic pattern that is used to validate the technique. Experiment results show that it can accurately group the electromagnetic patterns by which radiation assessment can be performed.

In graphene-based optoelectronic devices, the ultraweak interaction between a light and monolayer graphene leads to low optical absorption and low responsivity for the photodetectors and relative high half-wave voltage for the phase modulator. Here, an integration of the monolayer graphene onto the side-polished optical fiber is demonstrated, which is capable of providing a cost-effective strategy to enhance the light–graphene interaction, allowing us to obtain a highly efficient optical absorption in graphene and achieve multifunctions: photodetection and optical phase modulation. As a photodetector, the device has ultrahigh responsivity ( 1.5 × 10 7 A / W ) and high external quantum efficiency ( > 1.2 × 10 9 % ). Additionally, the polybutadiene/polymethyl methacrylate (PMMA) film on the graphene can render the device an optical phase modulator through the large thermo-optic effect of the PMMA. As a phase modulator, the device has a relatively low half-wave voltage of 3 V with a 16 dB extinction ratio in Mach–Zehnder interferometer configuration.

Nonintrusive electromagnetic interference (EMI) detection is a powerful method for EMI diagnosis in high-speed links and multiple signal PCB designs. However, due to the dispersive nature of signal delivery passages and interferences from neighborhood signals, it is very difficult to locate exactly the EMI source of two adjacent traces without contact. In this paper, a noncontact time-domain voltage measurement method is proposed to detect the EMI signals of two adjacent traces on a PCB. A near-field electric probe is employed and a reconstruction algorithm is developed to recover the voltage signals without contact. Through experimental benchmarks, it is demonstrated that the proposed method can successfully recover the common signals, differential signals, and non-correlated signals from the adjacent dual traces. It provides a convenient EMI source measurement method for high-speed and multiple signals PCB diagnosis and optimizations.

An analytic model of the field-to-line coupling in time domain for electrically small lines using a transverse electromagnetic (TEM) cell is proposed in this paper. This model uses mutual capacitance and mutual inductance to represent electric and magnetic field couplings which can be obtained based on voltage and current dividers. The measurement and calculation results validate the accuracy of the model and indicate relevant suppressions for radiated immunity. This model is convenient for fast radiated immunity estimations.

This paper presents the topical researches on novel microelectric devices in recent years. With the nanometerization of microelectric devices, new materials such as GaN, SiC, and new structures such as MEMS, SOI, SIP, have been adopted widely. We focus on their reliability studies, and then propose the methodology and suggestions on reliability studies of novel microelectronic devices.

With the decrease in the overall size and the rapid increase in the working frequencies of printed circuit boards, the reliability of solder joints, especially the high frequency signal transmission reliability has become the key factor in system reliability. In this paper, changes in RF impedance of solder joints in a temperature cycling environment was studied using time-domain reflectometry measurements. It was found that with the increase in the temperature cycle, the intermetallic compound layer gradually thickened, and even if no macro damage was found, the RF impedance increased. The transmission reliability of the high frequency signal was degraded.

In this paper, we investigate the conducted emission of I/O pins near power pairs of a microcontroller integrated circuit. Our investigation show that with the increase of the distance from the power pairs the I/O pin gives decreasing conducted emission. The spread of the conducted emission from power pairs to I/O pins can be depicted by mutual inductance and mutual capacitor in a lumped circuit model.

A model based on localized partition function and master equation was set up to calculate the zero-field-cooled (ZFC) and field-cooled (FC) curves of a non-interacting magnetic nanoparticle assembly with randomly oriented anisotropy. The peak temperature of the ZFC curve corresponds to the highest energy barrier that acts against the unblocking process, and could be described well by an equation covering the heating rate effect. The predicted H 2/3 field dependence of the peak temperature is in good agreement with published results.

The switch-mode power supply (SMPS) is being widely used in various fields. The reliability of SMPS is directly affected by the degradation and failure of magnetic component of transformer. It is well known that the loss of the magnetic component of transformer consist of iron loss and copper loss. In this paper, The pros and cons of several common loss measurement methods are discussed and a brief overview of temperature-controlled system for loss measurement of transformer in SMPS is proposed. The system can achieve these goals, within specified flux density and high frequency ranges, and at different temperatures, with high speed and accuracy, then MATLAB programming for data analysis and loss calculation. By doing this, The system can rapidly judge whether the damage of SMPS is caused by the loss of magnetic component.

In dealing with the problem of establishing control limits in short run production, Bayesian approach provides a effective way for are short run process control and are particularly attractive. In this paper, two quality control models for short run process are presented based on Bayesian analysis and the two models are compared. Models are focused on normally distributed data. The first way to establish model is through the posterior density of mean and variance of normally distributed data respectively and the second way is through the posterior predictive density. And the results deduced from two different ways are compared.

Lots of military equipments are in storage, and the equipments are need to evaluate whether showing degenerate character or not, or whether meeting the requirements to use continually or not. Electric components are basic elements, and it is important to evaluate the life character in storage. In this article, the typical components, tantalum capacitor, electromagnetic relays and resistor included, are analyzed with the way of external visual inspection, key electric meters test, inner visual inspection and 3 analysis cases show that external and inner visual inspection can find life characters of electric components, degeneration of key electric meter can be analyzed by key electric meter test. It can be analyzed effectively for life character of electric components in storage with those analysis ways.