Reversible logic gates were previously implemented in superconducting circuits as adiabatic-reversible gates, which are powered with a sufficiently slow clock. In contrast, we are studying ballistic-reversible gates, where fluxons serve to both encode the information and power the gates. No power is applied to the gate apart from the energy of the input fluxons, and the two possible flux polarities represent the bit states. Undamped long Josephson junctions (LJJs), where fluxons move at practically constant speed from inertia, form the input and output channels of the gates. LJJs are connected in the gates by circuit interfaces, which are designed to allow the ballistic scattering from input to output fluxon states, using the temporary excitation of a localized mode. The duration of the resonant scattering determines the operation time of the gate, approximately a few Josephson plasma periods. Due to the coherent conversions between fluxon and localized modes, the ballistic gates can be very efficient: In our simulations, only a few percent of the fluxon's energy are dissipated in the gate operation. Ballistic-reversible gates can be combined with other nonballistic gate circuits to extend the range of gate functionalities. Here, we describe how the cnot can be built as a structure that includes the Identity-else-Same-gives-not (IDSN) and store-and-launch (SNL) gates. The IDSN is a 2-b ballistic gate, which we describe and analyze in terms of equivalent 1-b circuits. The SNL is a clocking gate, which allows the storage of a bit and the clocked launch of a fluxon on a bit-state-dependent output path. In the cnot, the SNL gates provide the necessary routing and fluxon synchronization for the input to the IDSN gate.

中文翻译：

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具有优化 CNOT 门组件的可逆磁通子逻辑

可逆逻辑门以前在超导电路中作为绝热可逆门实现，由足够慢的时钟供电。相比之下，我们正在研究弹道可逆门，其中通量子既用于编码信息又为门供电。除了输入通量子的能量外，没有任何功率施加到门上，两种可能的通量极性代表位状态。无阻尼长约瑟夫森结 (LJJ)，其中通量子从惯性以几乎恒定的速度移动，形成门的输入和输出通道。LJJ 通过电路接口连接在门中，该接口旨在使用局部模式的临时激发，允许从输入通量状态到输出通量状态的弹道散射。共振散射的持续时间决定了门的操作时间，大约几个约瑟夫森等离子体周期。由于通量子和局部模式之间的相干转换，弹道门可以非常有效：在我们的模拟中，只有少数通量子的能量在门操作中耗散。弹道可逆门可以与其他非弹道门电路结合，以扩展门功能的范围。在这里，我们描述了如何将 cnot 构建为包括 Identity-else-Same-gives-not (IDSN) 和存储和启动 (SNL) 门的结构。IDSN 是一个 2-b 弹道门，我们根据等效的 1-b 电路对其进行描述和分析。SNL 是一个时钟门，它允许在位状态相关的输出路径上存储一个位和一个磁通的时钟启动。在 cnot 中，