Abstract
Shor’s factoring algorithm contains controlled modular exponentiation which can be further reduced as a series of controlled modular multipliers with constant. For the controlled modular multiplier with constant, this paper proposes a binary-exponent-based recombination (BER) protocol which could substantially reduce the number of addends. Based on the BER protocol, BER algorithms are constructed by the topdown hierarchy of controlled modular exponentiation, controlled modular multiplier with constant, controlled modular adder and plain adders. A complexity analysis reveals that BER algorithm reduces the number of plain adders in the controlled modular exponentiation by an average of about 42% compared with Vedral–Barenco–Ekert algorithm, thus significantly decreasing the depth and total Toffoli gates of the quantum circuits. The BER protocol can be widely used in various controlled modular multipliers as a promising ingredient of quantum factoring algorithm.





















Similar content being viewed by others
Explore related subjects
Discover the latest articles, news and stories from top researchers in related subjects.Availability of data and materials
The data that support the findings of this study are available from the corresponding author QA upon reasonable request.
References
Castelvecchi, D.: Preparing for qday. Nature 602, 198–201 (2022)
Shor, P.W.: Algorithms for quantum computation: discrete logarithms and factoring. In: Proceedings 35th Annual Symposium on Foundations of Computer Science, pp 124–134 ( 1994). IEEE
Nam, Y., Ross, N.J., Su, Y., Childs, A.M., Maslov, D.: Automated optimization of large quantum circuits with continuous parameters. npj Quantum Inf. 4(1), 1– 12 (2018)
Dumitrescu, E.: Tree tensor network approach to simulating Shor’s algorithm. Phys. Rev. A 96(6), 062322 (2017)
Markov, I.L., Saeedi, M.: Faster quantum number factoring via circuit synthesis. Phys. Rev. A 87(1), 012310 (2013)
Gouzien, E., Sangouard, N.: Factoring 2048-bit rsa integers in 177 days with 13,436 qubits and a multimode memory. Phys. Rev. Lett. 127, 140503 (2021). https://doi.org/10.1103/PhysRevLett.127.140503
Gidney, C., Ekerå, M.: How to factor 2048 bit rsa integers in 8 hours using 20 million noisy qubits. Quantum 5, 433 (2021)
Lucero, E., Barends, R., Chen, Y., Kelly, J., Mariantoni, M., Megrant, A., O’Malley, P., Sank, D., Vainsencher, A., Wenner, J., et al.: Computing prime factors with a Josephson phase qubit quantum processor. Nat. Phys. 8(10), 719–723 (2012)
Martin-Lopez, E., Laing, A., Lawson, T., Alvarez, R., Zhou, X.-Q., O’brien, J.L.: Experimental realization of Shor’s quantum factoring algorithm using qubit recycling. Nat. Photonics 6( 11), 773– 776 ( 2012)
Monz, T., Nigg, D., Martinez, E.A., Brandl, M.F., Schindler, P., Rines, R., Wang, S.X., Chuang, I.L., Blatt, R.: Realization of a scalable Shor algorithm. Science 351(6277), 1068–1070 (2016)
Rines, R., Chuang, I.: High performance quantum modular multipliers. arXiv preprint arXiv:1801.01081 (2018)
Peng, X., Liao, Z., Xu, N., Qin, G., Zhou, X., Suter, D., Du, J.: Quantum adiabatic algorithm for factorization and its experimental implementation. Phys. Rev. Lett. 101(22), 220405 (2008)
Nielsen, M.A., Chuang, I.L.: Quantum Computation and Quantum Information. Cambridge University Press, Cambridge ( 2000)
Ekerå, M., Håstad, J.: Quantum algorithms for computing short discrete logarithms and factoring rsa integers. In: International Workshop on Post-Quantum Cryptography, pp. 347– 363 (2017). Springer
Vedral, V., Barenco, A., Ekert, A.: Quantum networks for elementary arithmetic operations. Phys. Rev. A 54(1), 147 (1996)
Zalka, C.: Fast versions of Shor’s quantum factoring algorithm. arXiv preprint arXiv:quant-ph/9806084 (1998)
Van Meter, R., Itoh, K.M.: Fast quantum modular exponentiation. Phys. Rev. A 71(5), 052320 (2005)
Pavlidis, A., Gizopoulos, D.: Fast quantum modular exponentiation architecture for Shor’s factorization algorithm. Quantum Inf. Comput. 14(7 and 8), 649– 682 (2014)
Pham, P., Svore, K.M.: A 2D nearest-neighbor quantum architecture for factoring in polylogarithmic depth. Quantum Inf Comput 13(11 and 12), 0937– 0962 (2013)
Draper, T.G., Kutin, S.A., Rains, E.M., Svore, K.M.: A logarithmic-depth quantum carry-lookahead adder. Quantum Inf. Comput. 6(4), 351–369 (2006)
Beauregard, S.: Circuit for Shor’s algorithm using 2n+ 3 qubits. Quantum Inf. Comput. 3, 175–185 (2003)
Gidney, C.: Factoring with \(n+ 2\) clean qubits and \(n-1\) dirty qubits. arXiv preprint arXiv:1706.07884 (2017)
Davies, J., Rickerd, C.J., Grimes, M.A., Guney, D.O.: An n-bit general implementation of Shor’s quantum period-finding algorithm. arXiv preprint arXiv:1612.07424 (2016)
Beckman, D., Chari, A.N., Devabhaktuni, S., Preskill, J.: Efficient networks for quantum factoring. Phys. Rev. A 54(2), 1034 (1996)
Cuccaro, S.A., Draper, T.G., Kutin, S.A., Moulton, D.P.: A new quantum ripple-carry addition circuit. arXiv preprint arXiv:quant-ph/0410184 (2004)
Takahashi, Y., Kunihiro, N.: A linear-size quantum circuit for addition with no ancillary qubits. Quantum Inf. Comput. 5(6), 440–448 (2005)
Gossett, P.: Quantum carry-save arithmetic. arXiv preprint arXiv: quant-ph/9808061 (1998)
Oonishi, K., Tanaka, T., Uno, S., Satoh, T., Van Meter, R., Kunihiro, N.: Efficient construction of a control modular adder on a carry-lookahead adder using relative-phase Toffoli gates. IEEE Trans. Quantum Eng. 3, 1–18 (2021)
Draper, T.G.: Addition on a quantum computer. arXiv preprint arXiv:quant-ph/0008033 (2000)
Fowler, A.G., Devitt, S.J., Hollenberg, L.C.: Implementation of Shor’s algorithm on a linear nearest neighbour qubit array. Quantum Inf. Comput. 4(4), 237–251 (2004)
Zalka, C.: Shor’s algorithm with fewer (pure) qubits. arXiv preprint arXiv:quant-ph/0601097 (2006)
Gidney, C.: Approximate encoded permutations and piecewise quantum adders. arXiv preprint arXiv:1905.08488 (2019)
Pavlidis, A., Floratos, E.: Quantum-Fourier-transform-based quantum arithmetic with qudits. Phys. Rev. A 103, 032417 (2021)
Kutin, S.A.: Shor’s algorithm on a nearest-neighbor machine. arXiv preprint arXiv:quant-ph/0609001 (2006)
Gidney, C.: Windowed quantum arithmetic. arXiv preprint arXiv:1905.07682 (2019)
Nam, Y.S., Blümel, R.: Scaling laws for Shor’s algorithm with a banded quantum Fourier transform. Phys. Rev. A 87(3), 032333 (2013)
Pham, P., Svore, K.M.: A 2D nearest-neighbor quantum architecture for factoring in polylogarithmic depth. Quantum Inf. Comput. 13(11–12), 937–962 (2013)
Parker, S., Plenio, M.B.: Efficient factorization with a single pure qubit and log \(n\) mixed qubits. Phys. Rev. Lett. 85(14), 3049 (2000)
Acknowledgements
We thank Rutian Huang, Qing Yu, Xinyu Wu, Mingjun Cheng and Liangliang Yang for fruitful comments and discussions. This work is partially supported by the National Natural Science Foundation of China (Grant No. 60836001) and key R &D program of Guangdong province (Grant No. 2019B010143002).
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Code availability
The codes that implement the truth table of BER algorithm when the constant \(c=4\) and the modulo \(N=21\) using Qiskit are available from the authors on reasonable request.
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Appendices
Appendix A: BER procedures for mod 21
Figure 16 illustrates the procedures of BER protocol for \((-c^{-1})_{21}B\mathrm mod\) 21 where \(c=4\), and the result is presented in Eq. (19) of Sect. 3.3. Figure 17 displays the procedures of BER protocol for \(c^{-1}B\mathrm mod\) 21 where \(c=4\), and the result is presented in Eq. (20) of Sect. 3.3.
Appendix B: Quantum circuits of subtractor
The operation of subtracting yN is equivalent to adding the product of y and N’s complement \(y(2^{n+1}-N)\) in Eq. (24). Figure 18 depicts the two types of subtractors.
Appendix C: BER-addends for 303
Two typical cases of addends generated by BER protocol when factoring 303 are displayed in Fig. 19. All the addends in Fig. 19a are less than 303 and thus the augmentation is not needed when the constant multiplicand \(c=19\). However, Fig. 19b illustrates the result of BER protocol when the constant multiplicand \(c=280\). It can be seen that, if \(a_{i}=1\) \((i=0,\ldots , 8)\), then \(A_{3}=511>303\) and \(A_{4}=319>303\). Therefore, the augmentation of addends is required and the result is shown in Fig. 19c.
Appendix D: Parallelization in QFT plain adder
In the QFT plain adders, the controlled rotation gates corresponding to different \(a'_{j}\) could be parallelized. In Fig. 20a, a QFT plain adder using BER protocol for the case of \(n=5\) before parallelization is displayed. In Fig. 20b, the controlled rotation gates are rearranged into 9 time slices denoted as \(\mathrm TS~1-9\) in the parallelized QFT plain adder. The controlled rotation gates in each time slice could be carried out concurrently.
Appendix E: Truth table for BER-ModMULT-C
Figure 21 lists the truth table of controlled modular multiplier with constant \(c=4\) which is verified for each input \(A (0\le A<21)\) by using IBM Qiskit [37].
Rights and permissions
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
He, Y., Zhao, C., Dai, G. et al. Quantum modular multiplier via binary-exponent-based recombination. Quantum Inf Process 21, 391 (2022). https://doi.org/10.1007/s11128-022-03736-x
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s11128-022-03736-x