Investigation on multi-excitation mode for high-speed and low-latency AQFP circuits

方堃, 安藤拓生, 竹内尚輝, 山梨裕希, 吉川信行（横浜国大）

Abstract:Adiabatic quantum-flux-parametron (AQFP) circuits are very low-power because of zero static power consumption. Additionally, adiabatic switching operations enable AQFP circuits to reduce dynamic energy dissipation. In order to increase operation frequencies and to reduce latency in AQFP circuits, we herein propose multi-excitation AQFP (ME-AQFP) circuits, in which AQFP gates switch multiple times during a cycle of excitation currents. In the numerical simulation, we showed AQFP gates operating in the double-excitation mode, in which the circuits operate at 10 GHz with 5-GHz excitation currents. Moreover, we experimentally demonstrated several logic circuits, including an XOR gate in the double-excitation mode at low frequency and confirmed wide excitation margins of more than 20%. The above results indicate the possibility of high-speed AQFP circuits operating at higher than a few tens of GHz.