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Non-interactive quantum homomorphic encryption scheme based on the rotation operator

WANG ShuoLin, SHANG Tao, LIU JianWei

Published Nov 16, 2022• 5 citations

Abstract

Quantum homomorphic encryption (QHE) is an important branch of quantum cryptography. It can directly calculate the quantum ciphertext while ensuring calculation correctness and data security. QHE for a T-gate generates an additional S-gate. If this error is not eliminated, the desired output cannot be obtained. Using quantum gate teleportation can eliminate the S-error non-interactively, but increases the decryption complexity. This paper uses the rotation operator to realize QHE for the T / T^† -gate, and proposes a non-interactive QHE scheme. The decryption complexity of this scheme is O(1), and the encryption complexity is O(N) , where N is the number of quantum gates in the evaluated circuit. We prove that the scheme is information-theoretic secure and mathcalF-homomorphic, i.e., homomorphic for any quantum circuit, and implement QHE for a Toffoli-gate decomposition circuit on an IBM Quantum Experience platform.

DOI: 10.1360/sspma-2022-0381

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