This paper proposes a neuromorphic analog CMOS controller for interlimb coordination in quadruped locomotion. Animal locomotion, such as walking, running, swimming, and flying, is based on periodic rhythmic movements. These rhythmic movements are driven by the biological neural network, called the central pattern generator (CPG). In recent years, many researchers have applied CPG to locomotion controllers in robotics. However, most of these have been developed with digital processors and, thus, have several problems, such as high power consumption. In order to overcome such problems, a CPG controller with analog CMOS circuit is proposed. Since the CMOS transistors in the circuit operate in their subthreshold region and under low supply voltage, the controller can reduce power consumption. Moreover, low-cost production and miniaturization of controllers are expected. We have shown through computer simulation, such circuit has the capability to generate several periodic rhythmic patterns and transitions between their patterns promptly.

Cu-deficient layer (CDL) on Cu(In,Ga)Se 2 (CIGS) promotes Cd diffusion from CdS buffer layer and forms a valence band offset (ΔE V ) between CDL and CIGS. We quantitively demonstrate the effects of CDL formation on the performance of CIGS solar cells through experiments and theoretical simulation. To investigate the effects of Cd diffusion and ΔE V by CDL, theoretical analysis was carried out for a CIGS solar cell with a surface layer which simulated the CDL at CdS/CIGS interface. It was revealed that when electron concentration in n-type surface layer is higher than the absolute carrier concentration in CIGS absorber (N D > |N A, CIGS |), open-circuit voltage and fill factor are improved. Additionally, ΔE V ≥ 0.15 eV leads to the highest open-circuit voltage by suppression of interfacial recombination. Transmission electron microscope energy dispersive X-ray spectrometry and scanning spreading resistance microscopy were employed for the same cross section of a CIGS solar cell fabricated by three-stage process. Despite CDL with Cu/(Ga + In) of 0.31 formed on the surface had high Cd contents of 3.4 at%, its carrier concentration of 4.8 × 10 10 cm −3 was lower than that of 10 14 -10 16 cm −3 in grain interior owing to insufficient activation of Cd atoms. These results indicate the effectiveness of ΔE V formation by introducing CDL with low Cu/(Ga + In) of 0.31 to boost CIGS solar cell performance and difficulty in realizing N D > |N A, CIGS | by surface Cd doping.

International audience The purpose of this paper is to present the $q$-hook formula of Gansner type for a generalized Young diagram in the sense of D. Peterson and R. A. Proctor. This gives a far-reaching generalization of a hook length formula due to J. S. Frame, G. de B. Robinson, and R. M. Thrall. Furthurmore, we give a generalization of P. MacMahon's identity as an application of the $q$-hook formula. Le but de ce papier est présenter la $q$-hook formule de type Gansner pour un Young diagramme généralisé dans le sens de D. Peterson et R. A. Proctor. Cela donne une généralisation de grande envergure d'une hook length formule dû à J. S. Frame, G. de B. Robinson, et R. M. Thrall. Furthurmore, nous donnons une généralisation de l'identité de P. MacMahon comme une application de la $q$-hook formule.

Se irradiation with time, t Se, was introduced after the second stage of a three-stage process to control the Cu2Se layer during Cu(In,Ga)Se2 (CIGS) deposition. Open circuit voltage and fill factor of CIGS solar cells could be improved by introducing Se irradiation. We concluded that the control of the Cu2Se layer led to the formation of a Cu-depletion CIGS layer (CDL), which improved conversion efficiency owing to suppression of interfacial recombination by a valence band offset formed between CIGS and the CDL. Finally, highest efficiency of 19.8% was achieved with t Se of 5 min. This very simple and new technique is promising for the improvement of photovoltaic performance.

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The unintentional formation of a Cu depletion layer (CDL) on the surface of Cu(In,Ga)Se2 was observed in 1993, and CDLs have been expected to improve the performance of Cu(In,Ga)Se2 solar cells. However, methods of controlling CDLs have hitherto been unavailable. For the first time, we succeeded in controlling a uniform CDL on a Cu(In,Ga)Se2 surface by introducing irradiation with Se into the typical three‐stage growth process of Cu(In,Ga)Se2. We discuss the characterization and effects on device performance of CDLs. A uniform, smooth CDL with a thickness of 200 nm was formed at a Se irradiation time of 5 minutes, whereas the CDL formed at an irradiation time of 10 minutes was rough and non‐uniform. A maximum efficiency of 19.8% was achieved at an irradiation time of 5 minutes via the formation of a complete CDL. This simple, unique method may help to maximize efficiency of Cu(In,Ga)Se2 solar cells.

We have numerically studied the stochastic magnetization dynamics of a pair of spin torque nano oscillators (STNOs) under noisy current injection by using the Landau-Lifshitz-Gilbert-Slonczewski (LLGS) equation with a macro-spin approximation. Common noisy current injection into both STNOs is found to induce the phase synchronizations, where two STNOs show in-phase or anti-phase locked precession depending on the sequences of Gaussian white noise. The noise-induced synchronization could be a possible application for controlling the output power in the array of the STNOs.

We recently succeeded in controlling a Cu-deficient Cu(In,Ga)Se 2 layer (CDL) on a Cu(In,Ga)Se 2 (CIGS) surface by introducing an Se irradiation after the completion of the second stage in a three-stage process during CIGS growth. The CDL on the surface causes the formation of a valence band offset (ΔE V ) between the CDL and CIGS because the Cu vacancies decrease the valence band maximum of the CDL. Therefore, we can expect the suppression of recombination at the CdS/CIGS interface in CIGS solar cells due to the repelling of holes by ΔE V . The amount of knowledge regarding the properties of CDL/CIGS interfaces is observed to be quite small because a control technique for CDL has not been developed so far. In this study, the compositional and structural properties of an accurately controlled CDL/CIGS interface are investigated in detail. The composition of the interface between the CDL and CIGS is observed using an energy dispersive X-ray spectroscopy with the help of a transmission electron microscope. Using nanobeam electron diffraction and Fourier transfer mapping analysis, it is confirmed that the 1 12Þ ð plane in the CDL continuously grows on the 11 2Þ ð plane in CIGS. Further, these results indicate that a high-quality interface is formed between the CDL and CIGS, which contains only a small amount of dangling bonds. Finally, a high conversion efficiency of 19.4% is achieved in the CIGS solar cell, which can be attributed to the formation of CDL and effect of ΔE V .Cu(In,Ga)Se 2 (CIGS) is considered to be one of the most promising materials that can be incorporated into the thin film solar cells because it is possible to achieve high performance along with low costs. Recent performance enhancements achieving efficiencies over 20% have been realized by applying an alkaline post-deposition treatment (PDT) process. Currently, a high efficiency of 22.6% has been achieved by introducing RbF-PDT. [1] Using KF-PDT, a conversion efficiency of 20.4% for flexible CIGS solar cell containing a polyimide substrate has been achieved. It has been remarkably reported that a Cu-deficient condition is formed on the CIGS surface using KF-PDF. [2] To date, Cu-deficient layers (CDLs) have been unintentionally formed on a CIGS surface during CIGS growth as a result of the general fabrication process. [3,4] A positive effect is expected when a CDL is formed on the CIGS surface. It has been reported that the valence band maximum (E V ) decreases in Cu-deficient condition, which results in the formation of a valence band offset (ΔE V ) between CIGS and CDL, [5][6][7] whereas ΔE V causes the suppression of interfacial recombination at the n-type CdS buffer layer/CIGS absorber interface. [4,8,9] However, an accurate control method for CDL formation has not yet been revealed, despite numerous studies on CIGS solar cells. Recently, our group reported a control technique for CDL formation on a CIGS surface [10] by modifying the three-stage process without using the PDT process. A secondary Cu 2 Se layer is temporally segregated on the ...