Si-rich SiOx and amorphous Si clusters embedded in SiOx films were prepared by the radio-frequency magnetron cosputtering method and high-temperature annealing treatment.The threshold resistance switching behavior was...Si-rich SiOx and amorphous Si clusters embedded in SiOx films were prepared by the radio-frequency magnetron cosputtering method and high-temperature annealing treatment.The threshold resistance switching behavior was achieved from the memory mode by continuous bias sweeping in all films,which was caused by the formation of clusters due to the local overheating under a large electric field.Besides,the Ⅰ-Ⅴ characteristics of the threshold switching showed a dependence on the annealing temperature and the SiOx thickness.In particular,formation and rupture of conduction paths is considered to be the switching mechanism for the 39 nm-SiOx film,while for the 78 nm-SiOx film,adjusting of the Schottky barrier height between insulator and semiconductor is more reasonable.This study demonstrates the importance of investigation of both switching modes in resistance random access memory.展开更多
A switchable dual-wavelength erbium-doped fiber laser(EDFL) with tunable wavelength is demonstrated. The ring cavity consists of two branches with a fiber Bragg grating(FBG) and a spherical-shape structure as fiber fi...A switchable dual-wavelength erbium-doped fiber laser(EDFL) with tunable wavelength is demonstrated. The ring cavity consists of two branches with a fiber Bragg grating(FBG) and a spherical-shape structure as fiber filters, respectively. By adjusting the variable optical attenuator(VOA), the laser can be switched between the single-wavelength mode and the dual-wavelength mode. The spherical-shape structure has good sensitivity to the temperature. When the temperature changes from 30 °C to 190 °C, the central wavelength of the EDFL generated by the branch of spherical-shape structure varies from 1 551.6 nm to 1 561.8 nm, which means that the wavelength interval is tunable.展开更多
We theoretically investigated laser trimming to adjust grating offset in phase-shifted fiber grating coupler (FGC) for all-optical switching application. It was clarified that the trimming made the extinction ratio hi...We theoretically investigated laser trimming to adjust grating offset in phase-shifted fiber grating coupler (FGC) for all-optical switching application. It was clarified that the trimming made the extinction ratio higher in all-optical FGC switch.展开更多
INTRODUCTIONSwitching frequency is a very important parameter in switchingpower converters. As the switching frequency increases, the physicalsize of magnetic elements and other components in the circuit reducesignifi...INTRODUCTIONSwitching frequency is a very important parameter in switchingpower converters. As the switching frequency increases, the physicalsize of magnetic elements and other components in the circuit reducesignificantly. Switching frequency also plays a great role incontrol loop gain and compensation design. Switching frequency determinesthe maximum allowable bandwidth of the control loop.Switching frequency is also important parameter for EMI and noiseissues. The EMI spectrum is a direct function of the switching fre-展开更多
基金Project supported by the Open Project Program of Surface Physics Laboratory(National Key Laboratory)of Fudan University,China(Grant No.KF2015.02)the Open Project Program of National Laboratory for Infrared Physics,Chinese Academy of Sciences(Grant No.M201503)+1 种基金Zhejiang Provincial Science and Technology Key Innovation Team,China(Grant No.2011R50012)Zhejiang Provincial Key Laboratory,China(Grant No.2013E10022)
文摘Si-rich SiOx and amorphous Si clusters embedded in SiOx films were prepared by the radio-frequency magnetron cosputtering method and high-temperature annealing treatment.The threshold resistance switching behavior was achieved from the memory mode by continuous bias sweeping in all films,which was caused by the formation of clusters due to the local overheating under a large electric field.Besides,the Ⅰ-Ⅴ characteristics of the threshold switching showed a dependence on the annealing temperature and the SiOx thickness.In particular,formation and rupture of conduction paths is considered to be the switching mechanism for the 39 nm-SiOx film,while for the 78 nm-SiOx film,adjusting of the Schottky barrier height between insulator and semiconductor is more reasonable.This study demonstrates the importance of investigation of both switching modes in resistance random access memory.
基金supported by the National High Technology Research and Development Program of China(No.2013AA014201)the Tianjin Youth Science Foundation(No.13JCQNJC01800)
文摘A switchable dual-wavelength erbium-doped fiber laser(EDFL) with tunable wavelength is demonstrated. The ring cavity consists of two branches with a fiber Bragg grating(FBG) and a spherical-shape structure as fiber filters, respectively. By adjusting the variable optical attenuator(VOA), the laser can be switched between the single-wavelength mode and the dual-wavelength mode. The spherical-shape structure has good sensitivity to the temperature. When the temperature changes from 30 °C to 190 °C, the central wavelength of the EDFL generated by the branch of spherical-shape structure varies from 1 551.6 nm to 1 561.8 nm, which means that the wavelength interval is tunable.
文摘We theoretically investigated laser trimming to adjust grating offset in phase-shifted fiber grating coupler (FGC) for all-optical switching application. It was clarified that the trimming made the extinction ratio higher in all-optical FGC switch.
文摘INTRODUCTIONSwitching frequency is a very important parameter in switchingpower converters. As the switching frequency increases, the physicalsize of magnetic elements and other components in the circuit reducesignificantly. Switching frequency also plays a great role incontrol loop gain and compensation design. Switching frequency determinesthe maximum allowable bandwidth of the control loop.Switching frequency is also important parameter for EMI and noiseissues. The EMI spectrum is a direct function of the switching fre-
