量子可逆逻辑电路中单个门故障的在线检测方法

Online detection method for single gate fault in quantum reversible logic circuits

可逆计算满足未来计算的需要,已成为量子计算、低能耗计算等新兴领域的研究基础。目前,研究者仅探讨了可逆电路的在线检错,在线纠错还未提出解决办法。分析论证了Toffoli可逆电路在发生单个门故障时,产生的错误输出具有互补特性。基于该特性,提出了一种在线纠错方法,将已有电路自动转换成在线纠错电路。该方法实时检测电路的输出错误,若出错,将错误输出对应的正确输入加载至原有电路得到正确输出,从而纠正单个门故障引起的多位输出错误,实现"无垃圾输出"的在线纠错。对Revlib中的一组电路进行实验,结果表明用所提方法构建的在线纠错电路在量子成本、垃圾输出、可逆门数目和传输线数上都明显优于传统的三模冗余方法(TMR)。

Reversible computing can satisfy the computation demands in future, which has become the foundation for new research areas like quantum computing and ultra low power computing. Many researchers discussed online error detection techniques of reversible cir- cuits, however there is still no solution about the online error correction. This paper analyzes and proves that in a Toffoli network with single failed gate, the generated error outputs are complementary to each other. Based on this characteristic, a new online error correc- tion method is proposed, which can convert the existing circuit into a new circuit with online error correction. This method detects the circuit output errors in real time, and if there are errors, then it will load the right inputs corresponding to the wrong outputs to the origi- nal circuit and get the correct outputs. This method can fix the one- or multi-bit errors in the output caused by single failed gate, and re- move all the garbage outputs. The experiment on one set of the circuits in Revlib was conducted, and the experiment results show that the proposed method is obviously better than the traditional triple module redundancy （TMR） method in terms of quantum cost, garbage output, number of reversible gates and number of transmission lines.