In this article, we demonstrate that, by employing the OpenPulse design kit for IBM superconducting quantum devices, the controlled-V gate ( cv gate) can be implemented in about half the gate time to the controlled-X gate ( cx or cnot gate) and consequently 65.5% reduced gate time compared to the cx -based implementation of cv […]
Quantum error correction (QEC) is required in quantum computers to mitigate the effect of errors on physical qubits. When adopting a QEC scheme based on surface codes, error decoding is the most computationally expensive task in the classical electronic back-end. Decoders employing neural networks (NN) are well-suited for this task but their hardware implementation has […]
We present a divide-and-conquer approach to deterministically prepare Dicke states |Dnk⟩ (i.e., equal-weight superpositions of all n -qubit states with Hamming weight k ) on quantum computers. In an experimental evaluation for up to n=6 qubits on IBM Quantum Sydney and Montreal devices, we achieve significantly higher state fidelity compared to previous results. The fidelity gains are achieved through several techniques: our circuits […]
Variational quantum algorithms (VQAs) are prime contenders to gain computational advantages over classical algorithms using near-term quantum machines. As such, many endeavors have been made to accelerate the optimization of modern VQAs in past years. To further improve the capability of VQAs, here, we propose a quantum distributed optimization scheme (dubbed as QUDIO), whose back […]
The discrete logarithm problem (DLP) is the basis for several cryptographic primitives. Since Shor’s work, it has been known that the DLP can be solved by combining a polynomial-size quantum circuit and a polynomial-time classical postprocessing algorithm. The theoretical result corresponds the situation where a quantum device working with a medium number of qubits of […]
Quantum volume (QV) has become the de-facto standard benchmark to quantify the capability of noisy intermediate-scale quantum (NISQ) devices. While QV values are often reported by NISQ providers for their systems, we perform our own series of QV calculations on 24 NISQ devices currently offered by IBM Q, IonQ, Rigetti, Oxford Quantum Circuits, and Quantinuum […]
Quantum computing (QC) holds great promise to open up a new era of computing and has been receiving significant attention recently. To overcome the performance limitations of near-term QC, utilizing the current quantum computers to complement classical techniques for solving real-world problems is of utmost importance. In this article, we develop QC-based solution strategies that […]
The National Aeronautics and Space Administration’s (NASA) Deep Space Network (DSN) is responsible for communication and navigation for several NASA and international missions. The DSN comprises three complexes located in Goldstone (California, USA), Cambera (Australia), and Madrid (Spain). This distribution in longitude guarantees a full sky coverage. Each complex has one 70-m and several 34-m […]
Currently available quantum computers are prone to errors. Circuit optimization and error mitigation methods are needed to design quantum circuits to achieve better fidelity when executed on NISQ hardware. Dynamical decoupling (DD) is generally used to suppress the decoherence error, and different DD strategies have been proposed. Moreover, the circuit fidelity can be improved by […]
In this article, a quasi-elliptical geometry and the iris technique are applied to a multimode cavity to manipulate the resonant mode in the desired direction for quantum memories. By applying quasi-elliptical geometry, the characteristics of monotonically increasing, equally spaced, and monotonically decreasing frequency intervals between the modes are realized. To manipulate a certain mode, an […]