In an article published in 2009, Brun et al. proved that in the presence of a “Deutschian” closed timelike curve, one can map K distinct nonorthogonal states (hereafter, input set) to the standard orthonormal basis of a K -dimensional state space. To implement this result, the authors proposed a quantum circuit that includes, among SWAP […]
The IEEE Transactions on Quantum Engineering has met all requirements for indexing in the Scopus database and has been accepted! Congratulations to EiC, Britton Plourde and the entire Editorial Board!
Variational quantum eigensolver (VQE) is a promising algorithm for near-term quantum machines. It can be used to estimate the ground state energy of a molecule by performing separate measurements of O(N 4 ) terms. This quartic scaling appears to be a significant obstacle to practical applications. However, we note that it empirically reduces to O(N 3 ) when we […]
We provide a procedure to construct entanglement-assisted Calderbank-Shor-Steane (CSS) codes over qudits from the parity check matrices of two classical codes over F q , where q = p k , p is prime, and k is a positive integer. The construction procedure involves the proposed Euclidean Gram-Schmidt orthogonalization algorithm, followed by a procedure to extend the quantum operators […]
Enhancing a Near-Term Quantum Accelerator’s Instruction Set Architecture for Materials Science Applications
Quantum computers with tens to hundreds of noisy qubits are being developed today. To be useful for real-world applications, we believe that these near-term systems cannot simply be scaled-down non-error-corrected versions of future fault-tolerant large-scale quantum computers. These near-term systems require specific architecture and design attributes to realize their full potential. To efficiently execute an […]
Abstract: Quantum random-access lookup of a string of classical bits is a necessary ingredient in several important quantum algorithms. In some cases, the cost of such quantum random-access memory (qRAM) is the limiting factor in the implementation of the algorithm. In this article, we study the cost of fault-tolerantly implementing a qRAM. We construct and […]
Abstract: To quantify security levels in a postquantum scenario, it is common to use the quantum resources needed to attack the Advanced Encryption Standard (AES) as a reference value. Specifically, in the National Institute of Standards and Technology’s ongoing postquantum standardization effort, different security categories are defined that reflect the quantum resources needed to attack […]