Background: In this article, we have proposed a new reversible quantum circuit block
along with the Quantum Cost (QC), Constant Input (CI), Garbage Output (GO) and delay optimized
code converter using quantum circuit block.
Methods: Initially, new quantum circuit block has been designed and later reversible code converter
circuits have been implemented using it. The proposed new quantum block used to design 2’s complement
code converter (2SCCC), cost efficient BCD to Excess-3 Code Converter (BECC) and can
also be used to implement different logic functions. The QC of proposed quantum circuit block is 8.
The QC and delay of the proposed 2SCCC is 8 and 1 respectively. Similarly, the QC and delay of the
proposed BECC is 11 and 2, respectively. The proposed cost efficient BECC is designed using two
NOT gate, one Feynman gate and one new quantum circuit block with QC is 11.
Results: The improvement of QC for 2SCCC and BECC is 27.27 % and 21.43%, respectively. The
improvement of delay for 2SCCC and BECC are 66.67% and 50%, respectively, compared with respect
to the latest reported results.
Conclusion: So the improvement of QC and delay are very high using QCB.