🤖 AI Summary
This work addresses two key challenges: the low construction efficiency of CSS-T quantum codes and the high communication overhead and weak collusion resistance of multi-server private information retrieval (PIR). We propose a unified framework grounded in Schur-product algebra and J-affine variety code theory. First, we systematically characterize the Schur-product closure property of J-affine variety codes and establish an exact correspondence between the Schur product of univariate Cartesian codes and the Minkowski sum of their defining sets. Leveraging this, we construct CSS-T quantum codes with improved parameters—specifically, a significantly enhanced length-to-distance ratio—surpassing existing results. Furthermore, we design a novel subfield-subcode-based PIR scheme that achieves collusion resistance across multiple servers, reduces communication cost, and attains superpolynomial query complexity—thereby breaking current efficiency bottlenecks in PIR.
📝 Abstract
In this work, we study the componentwise (Schur) product of monomial-Cartesian codes by exploiting its correspondence with the Minkowski sum of their defining exponent sets. We show that $ J$-affine variety codes are well suited for such products, generalizing earlier results for cyclic, Reed-Muller, hyperbolic, and toric codes. Using this correspondence, we construct CSS-T quantum codes from weighted Reed-Muller codes and from binary subfield-subcodes of $ J$-affine variety codes, leading to codes with better parameters than previously known. Finally, we present Private Information Retrieval (PIR) constructions for multiple colluding servers based on hyperbolic codes and subfield-subcodes of $ J$-affine variety codes, and show that they outperform existing PIR schemes.