Millivolt Switches Will Support Better Energy-Reliability Tradeoffs.
Abstract not provided.
Debenedictis, Erik↗
SEARCH · Engineering Papers
Results for “Switch”
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In-plane current-driven spin-orbit torque switching in perpendicularly magnetized films with enhanced thermal tolerance
Here, we study spin-orbit-torque (SOT)-driven magnetization switching in perpendicularly magnetized Ta/Mo/Co 40 Fe 40 B 20 (CoFeB)/MgO films. The thermal tolerance of the perpendicular magnetic anisotropy (PMA) is enhanced, and the films sustain the PMA at annealing temperatures of up to 430 C, due to the ultra-thin Mo layer inserted between the Ta and CoFeB layers. More importantly, the Mo insertion layer also allows for the transmission of the spin current generated in the Ta layer due to spin Hall effect, which generates a damping-like SOT and is able to switch the perpendicular magnetization. When the Ta layer is replaced by a Pt layer, i.e., in a Pt/Mo/CoFeB/MgO multilayer, the direction of the SOT-induced damping-like effective field becomes opposite because of the opposite sign of spin Hall angle in Pt, which indicates that the SOT-driven switching is dominated by the spin current generated in the Ta or Pt layer rather than the Mo layer. Quantitative characterization through harmonic measurements reveals that the large SOT effective field is preserved for high annealing temperatures. This work provides a route to applying SOT in devices requiring high temperature processing steps during the back-end-of-line processes.
42 ENGINEERING↗
Organization of the channel-switching process in parallel computer systems based on a matrix optical switch
After a classification and analysis of electronic and optoelectronic switching devices, the design principles and structure of a matrix optical switch is described. The switching and pair-exclusion operations in this type of switch are examined, and a method for the optical switching of communication channels is elaborated. Finally, attention is given to the structural organization of a parallel computer system with a matrix optical switch.
Golomidov, Y. V.↗
Finite Ground Coplanar Waveguide Shunt MEMS Switches for Switched Line Phase Shifters
Switches with low insertion loss and high isolation are required for switched line phase shifters and the transmit/receive switch at the front end of communication systems. A Finite Ground Coplanar (FGC) waveguide capacitive, shunt MEMS switch has been implemented on high resistivity Si. The switch has demonstrated an insertion loss of less than 0.3 dB and a return loss greater than 15 dB from 10 to 20, GHz. The switch design, fabrication, and characteristics are presented.
Ponchak, George E.↗
Gate Drive Technology Evaluation and Development to Maximize Switching Speed of SiC Discrete Devices and Power Modules in Hard Switching Applications
To understand the limitation of maximizing the switching speed of SiC low current discrete devices and high current power modules in hard switching applications, double pulse tests are conducted and the testing results are analyzed. For power modules, the switching speed is generally limited by the parasitics rather than the gate drive capability. For the discrete SiC device, the conventional voltage source gate drive (VSG) is not sufficient to maximize the switching speed even if the external gate resistance is minimized. The limitation of existing current source gate drives (CSG) are analyzed, and a CSG dedicated for SiC discrete devices is proposed, which can provide constant current during the switching transient regardless of the high Miller voltage and large internal gate resistance. Compared with the conventional VSG, the proposed CSG achieves 67% faster turnon time and 50% turn-off time, and 68% reduction in switching loss at full load condition.
Handong Gui↗
A viral-fusion-peptide-like molecular switch drives membrane insertion of botulinum neurotoxin A1
Abstract not provided
Lam, Kwok-ho↗
Three-Dimensional Fully-Coupled Electrical and Thermal Transport Model of Dynamic Switching in Oxide Memristors.
Abstract not provided.
Gao, Xujiao↗
A high capacity satellite switched TDMA microwave switch matrix
A description is given of the conceptual design of a high-capacity satellite switched-time division multiple access (SS-TDMA) microwave switch matrix fabricated with GaAs monolithic microwave integrated circuits (MMICs), including integration of both microwave and control logic circuits into the monolithic design. The technology required for a 30/20 GHz communications system includes an on-board SS-TDMA switch matrix. A conceptual design study that has been completed for a wideband, high-capacity (typically 100 x 100) channel switch matrix using technology anticipated for 1987 is described, noting that the study resulted in a switch matrix design concept using a coupled crossbar architecture implemented with MMIC. The design involves basic building block MMIC, permitting flexible growth and efficient wraparound redundancy to increase reliability.
Cory, B. J.↗
Towards smart corrective switching: analysis and advancement of PJM's switching solutions
Transmission switching, as a power flow control mechanism that can reduce costs and improve reliability, has gained a lot of attention during the last decade. Despite its benefits, industry adoption has been very limited due to its computational complexity, stability and AC performance concerns. Pennsylvania New Jersey Maryland (PJM) has published a list of corrective switching solutions to relieve actual and post‐contingency network violations. The list is developed based on operators ’ prior knowledge and offline studies. This study employs a fast AC‐based real‐time contingency analysis (RTCA) tool with corrective transmission switching (CTS) functionality to analyse PJM's switching solutions with actual PJM data. The results show that the RTCA CTS tool is almost always able to find solutions that perform better than, or equally as well as, PJM's solutions. The results also show that PJM's list identifies solutions for only 3% of the problematic contingencies with post‐contingency violations over the course of one week. The RTCA CTS tool, however, is able to find corrective TS solutions for almost all the cases. The results suggest that CTS is ripe for industry adoption. The tool provides significant savings and would pave the road towards a smarter transmission network as an essential ingredient of the future smart grid.
Balasubramanian, Pranavamoorthy↗
In-operando hard X-ray photoelectron spectroscopy study on the impact of current compliance and switching cycles on oxygen and carbon defects in resistive switching Ti/HfO{sub 2}/TiN cells
In this study, direct experimental materials science evidence of the important theoretical prediction for resistive random access memory (RRAM) technologies that a critical amount of oxygen vacancies is needed to establish stable resistive switching in metal-oxide-metal samples is presented. In detail, a novel in-operando hard X-ray photoelectron spectroscopy technique is applied to non-destructively investigates the influence of the current compliance and direct current voltage sweep cycles on the Ti/HfO{sub 2} interface chemistry and physics of resistive switching Ti/HfO{sub 2}/TiN cells. These studies indeed confirm that current compliance is a critical parameter to control the amount of oxygen vacancies in the conducting filaments in the oxide layer during the RRAM cell operation to achieve stable switching. Furthermore, clear carbon segregation towards the Ti/HfO{sub 2} interface under electrical stress is visible. Since carbon impurities impact the oxygen vacancy defect population under resistive switching, this dynamic carbon segregation to the Ti/HfO{sub 2} interface is suspected to negatively influence RRAM device endurance. Therefore, these results indicate that the RRAM materials engineering needs to include all impurities in the dielectric layer in order to achieve reliable device performance.
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
In-situ observation of self-regulated switching behavior in WO{sub 3-x} based resistive switching devices
The transmittance of tungsten oxides can be adjusted by oxygen vacancy (V{sub o}) concentration due to its electrochromic property. Here, we report an in-situ observation of resistive switching phenomenon in the oxygen-deficient WO{sub 3-x} planar devices. Besides directly identifying the formation/rupture of dark-colored conductive filaments in oxide layer, the stripe-like WO{sub 3-x} device demonstrated self-regulated switching behavior during the endurance testing, resulting in highly consistent switching parameters after a stabilizing process. For very high V{sub o}s mobility was demonstrated in the WO{sub 3-x} film by the pulse experiment, we suggested that the electric-field-induced homogeneous migration of V{sub o}s was the physical origin for such unique switching characteristics.
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
Effect of heavy metal layer thickness on spin-orbit torque and current-induced switching in Hf|CoFeB|MgO structures
We study the heavy metal layer thickness dependence of the current-induced spin-orbit torque (SOT) in perpendicularly magnetized Hf|CoFeB|MgO multilayer structures. The damping-like (DL) current-induced SOT is determined by vector anomalous Hall effect measurements. A non-monotonic behavior in the DL-SOT is found as a function of the thickness of the heavy-metal layer. The sign of the DL-SOT changes with increasing the thickness of the Hf layer in the trilayer structure. As a result, in the current-driven magnetization switching, the preferred direction of switching for a given current direction changes when the Hf thickness is increased above ∼7 nm. Although there might be a couple of reasons for this unexpected behavior in DL-SOT, such as the roughness in the interfaces and/or impurity based electric potential in the heavy metal, one can deduce a roughness dependence sign reversal in DL-SOT in our trilayer structure.
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
Q-switched and gain-switched Fe:ZnSe lasers tunable over 360–515 µm
We report on room temperature gain-switched and Q-switched Fe:ZnSe lasers tunable over 3.60–5.15 µm pumped by radiation of an 2.94 µm Er:YAG laser. The maximum output energy was measured to be 5 mJ under 15 mJ of pump energy in gain-switched regime. We also demonstrated a mechanically Q-switched regime of oscillation of Fe:ZnSe lasers. This approach could be attractive for the development of high-energy short-pulse solid-state mid-IR systems operating over 3.6–5.2 µm spectral range.
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
Switching Transition Analysis and Optimization for Bidirectional CLLC Resonant DC Transformer
Not provided.
Engineering↗
Deep Optical Switching on Subpicosecond Timescales in an Amorphous Ge Metamaterial
Active nanostructured optical components show promise as potential building blocks for novel light-based computing and data processing architectures. However, nanoscale all-optical switches that have low activation powers and high-contrast ultrafast switching have been elusive so far. Here, pump–probe measurements performed on amorphous-Ge-based micro-resonator metasurfaces that exhibit strong resonant modes in the mid-infrared are reported. Relative change is observed in transmittance of ΔT/T ≈ 1 with picosecond (down to τ ≈ 0.5 ps) free carrier relaxation rates, obtained with very low pump fluences of 50 μJ cm –2 . In this work, these observations are attributed to efficient free carrier promotion, affecting light transmittance via high quality-factor optical resonances, followed by an increased electron–phonon scattering of free carriers due to the amorphous crystal structure of Ge. Full-wave simulations based on a permittivity model that describes free-carrier damping through crystal structure disorder find excellent agreement with the experimental data. These findings offer an efficient and robust platform for all-optical switching at the nanoscale.
36 MATERIALS SCIENCE↗
Reversible Morphology Switching of Colloidal Particles
A facile method has been discovered that enables switching of non-cross-linked poly(styrene) (Nx-PS) colloidal particle morphologies, including spherical and anisotropic convex- convex, plano-convex, and concave-convex. The anisotropic morphologies can be achieved readily from spherical Nx-PS particles through control of annealing time at elevated temperatures or surfactant concentration. These anisotropic morphologies can be reversed to spherical at lower temperatures, and reversible morphology switching between any pair of anisotropic morphologies also can be attained. This approach to particle morphology switching establishes a straightforward method for the synthesis of designer anisotropic particles using commercially available spherical particles as starting materials.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗