Novel latch for adiabatic quantum-flux-parametron logic

Abstract

Measurement of 10 zJ energy dissipation of adiabatic quantum-flux-parametron logic using a superconducting resonator Appl. Phys. Lett. 102, 052602 (2013); 10.1063/1.4790276Rapid single-flux quantum logic using π-shifters A 3 bit single flux quantum shift register based on high-T c bicrystal Josephson junctions operating at 50 K We herein propose the quantum-flux-latch (QFL) as a novel latch for adiabatic quantum-fluxparametron (AQFP) logic. A QFL is very compact and compatible with AQFP logic gates and can be read out in one clock cycle. Simulation results revealed that the QFL operates at 5 GHz with wide parameter margins of more than 622%. The calculated energy dissipation was only $0.1 aJ/bit, which yields a small energy delay product of 20 aJÁps. We also designed shift registers using QFLs to demonstrate more complex circuits with QFLs. Finally, we experimentally demonstrated correct operations of the QFL and a 1-bit shift register (a D flip-flop). V C 2014 AIP Publishing LLC.

High-Speed Experimental Demonstration of Adiabatic Quantum-Flux-Parametron Gates Using Quantum-Flux-Latches

“…A QFL is composed of only three junctions and requires only one clock cycle for both read and write. We reported an experimental demonstration of a QFL and a 1-bit shift register using QFLs in a previous study [10].…”

“…Manuscript We designed and implemented several AQFP logic circuits [8], including a majority gate and a full adder. In addition, we proposed and designed the quantum-flux-latch (QFL) [9], [10] as a novel latch for AQFP logic to achieve practical energyefficient computing systems using AQFP logic. However, these gates were demonstrated only at a low speed of ∼100 kHz, because of the lack of high-speed test circuits.…”

Full-Gate Verification of Superconducting Integrated Circuit Layouts With InductEx

“…For RSFQ cells in general, the average solution time when resistance is modeled is 50%-100% longer than for inductance-only models, whereas it is only around 5% longer for circuits with low junction counts and no resistive biasing such as AQFP cells [23]. An excerpt from the solution output, which contains inductance, resistance, and critical current values, is shown in Fig.…”

Fast Multicore FastHenry and a Tetrahedral Modeling Method for Inductance Extraction of Complex 3D Geometries

“…It has 2 ports and a slender line geometry, and uses 7,635 filaments. The second is an 8 port AQFP cell [12] with 23,090 superconductive and normal filaments. The third is a 21 port RSFQ toggle flip-flop (TFF) [13] with 37,247 filaments.…”