Reversible computing [1, 2] can be carried out in a thermodynamically reversible manner, or without energy dissipation. We have been studying reversible circuits using adiabatic quantum-flux-parametron (AQFP) logic [3], which is an energy-efficient superconductor logic family. In this presentation, we report recent research on reversible circuits using AQFP logic. We show the minimum energy dissipation required for general information processing through numerical simulation using reversible circuits comprising a reversible QFP (RQFP) [4], which is a reversible logic gate based on AQFP logic [5]. We also show measurement results of combinational and sequential circuits using RQFP gates for reversible microprocessors [6]. Finally, we show compact reversible circuits using AQFP logic with delay line-based Bennett clocking [7].
[1] E. Fredkin and T. Toffoli, Int. J. Theor. Phys., 21, 219–253 (1982).
[2] C. H. Bennett, Int. J. Theor. Phys., 21, 905–940 (1982).
[3] N. Takeuchi et al., Supercond. Sci. Technol., 26, 035010 (2013).
[4] N. Takeuchi et al., Sci. Rep., 4, 6354 (2014).
[5] T. Yamae et al., J. Appl. Phys., 135, 063902 (2024).
[6] T. Yamae et al., Supercond. Sci. Technol., 32, 035005 (2019).
[7] C. H. Bennett, IBM J. Res. Dev., 17, 525–532 (1973).
This study was supported by JSPS KAKENHI (Grant No. JP19H05614) and JST, PRESTO (Grant No. JPMJPR22B9), Japan. The circuits were fabricated in the Superconducting Quantum Circuit Fabrication Facility (Qufab) of the National Institute of Advanced Industrial Science and Technology (AIST).
Keywords: Reversible computing, Quantum flux parametron, Adiabatic logic, Bennett clocking