Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Fortschritte der Physik

Dynamical Controls for Improving Quantum Search Algorithm Through Flux Qubits System

Ali H. Homid, Mahmoud Abdel‐Aty, Tarek M. El-Shahat, Hichem Eleuch, A.‐S. F. Obada

Published Apr 10, 2018• 1 citation
Publisher

Abstract

Abstract A new technique was developed to generate the dynamical quantum gates, depend on the ferromagnetism and antiferromagnetism phenomena in the superconducting flux qubits system at the same interaction time. According to the dynamical controls techniques of such gates, we invoke and synthesize a new algorithm called the dynamical quantum search algorithm. The Grover algorithm was obtained at a specified time for the current algorithm. This algorithm was distinguished by accuracy in obtaining high probability of finding any marked state in a shorter time compared with Grover algorithm time. The algorithm performance was improved with respect to different values of the dynamical controls.

DOI
10.1002/prop.201700080

Related papers

Multi-Qubit Dynamical Quantum Search Algorithm with Dissipation

Ali H. Homid, Mahmoud Abdel‐Aty, A.‐S. F. Obada

We invoke an efficient search algorithms as a key challenge in multi-qubit quantum systems. An original algorithm called dynamical quantum search algorithm from which Grover algorithm is obtained at a specified time is presented. This algorithm is distinguished by accuracy in obtaining high probability of finding any marked state in a shorter time than Grover algorithm time. The algorithm performance can be improved with respect to the different values of the controlled phase. A new technique is used to generate the dynamical quantum gates in the presence of dissipation effect that helps in implementing the current algorithm.

arXiv:1509.04858•Sep 16, 2015•0 citations

Spin Iteration Quantum Search Algorithm

Jian Cao

In order to improve the searching efficiency of the Grover algorithm,a new quantum search algorithm was presented based on the Grover algorithm.This quantum search algorithm makes full use of the structural information of states,and spin quantum gates are designed in light of different initialized quantum states and searched ground states,then the new quantum gates are used to spin iteration.The research shows that compared with the Grover algorithm,the presented algorithm decreases iteration times.The feasibility and validity of this algorithm are verified through practical examples.

Journal of Southwest Jiaotong University•Jan 1, 2010•1 citation

Tomography of Qubit States and Implementation of Quantum Algorithms by Unipolar Pulses

M. V. Bastrakova, N. V. Klenov, Сатанин Аркадий Михайлович

Abstract The conventional technique for controlling the states of individual qubits and quantum registers is based on the use of high-frequency modulated pulses whose carrier frequency is close to the transition frequency between the ground states of “artificial atoms” and “molecules” (the Rabi technique). In this paper, an alternative concept for controlling superconducting qubits is developed that is based on the idea of fast excitation of a quantum system by solitary unmodulated pulses. The formation of entangled Bell states in a two-qubit superconducting register under the action of field pulses obtained by rapid single flux quantum (RSFQ) devices is demonstrated by numerical simulation. The tomography of quantum states is performed by solving the density matrix equation. It is shown that the technique of “unipolar pulses” allows one to speed up the formation of entangled states (at picosecond times) with a fidelity of 95–98%. The execution of the basic quantum algorithms is demonstrated: the Deutsch–Jozsa algorithm with an accuracy of more than 98% and Grover’s algorithm with an accuracy of 93%.

Journal of Experimental and Theoretical Physics•Oct 1, 2020•17 citations

Analysis of Grover’s quantum search algorithm as a dynamical system

Ofer Biham, Daniel Shapira, Yishai Shimoni

Grover's quantum search algorithm is analyzed for the case in which the initial state is an arbitrary pure quantum state $|\ensuremath{\varphi}〉$ of n qubits. It is shown that the optimal time to perform the measurement is independent of $|\ensuremath{\varphi}〉,$ namely, it is identical to the optimal time in the original algorithm in which $|\ensuremath{\varphi}〉=|0〉,$ with the same number of marked states, r. The probability of success ${P}_{\mathrm{s}}$ is obtained in terms of the amplitudes of the state $|\ensuremath{\varphi}〉$ and is shown to be independent of r. A class of states, which includes fixed points and cycles of the Grover iteration operator, is identified. The relevance of these results in the context of using the success probability as an entanglement measure is discussed. In particular, the Groverian entanglement measure, previously limited to a single marked state, is generalized to the case of several marked states.

arXiv:quant-ph/0307141•Physical Review A•Aug 29, 2003•15 citations

Implementation of a many-qubit Grover search with trapped ultracold ions

Wan-Li Yang, Hua Wei, Changyong Chen +1 more

We propose a potentially practical scheme for realization of an n-qubit (n>2) conditional phase flip (CPF) gate and implementation of Grover's search algorithm in an ion-trap system. We demonstrate, both analytically and numerically, that our scheme could be achieved efficiently to find a marked state with high fidelity and high success probability. We also show the merits of the proposal that the increase of the ion number can improve the fidelity and success probability of the CPF gate. The required operations for a Grover search are very close to the capabilities of current ion-trap techniques.

arXiv:0809.3053•Journal of the Optical Society of America B•Sep 25, 2008•7 citations

Co-Design of a Quantum Circuit using QGHNN for High Separate Fidelity and Maximum Grover Algorithm Accuracy

Mahdi Esmaeili, Katayoun Emadzadeh, M. Hossein Eskandari +5 more

Abstract A hybrid physics–machine-learning framework is introduced for the joint optimization of separate fidelity and Grover algorithm performance in superconducting quantum processors. The method combines a Hamiltonian-based open-quantum-system model of a two-qubit architecture coupled through a bus resonator with a QGHNN. Readout performance is evaluated via the Lindblad master-equation simulation of the dispersive measurement process, in which state-dependent resonator dynamics are mapped to realistic I/Q distributions and classified to estimate single-shot measurement fidelity. In parallel, algorithmic performance is assessed by simulating a two-qubit Grover search circuit in the presence of dissipation and dephasing, using effective cross-Kerr interactions derived from the underlying circuit parameters. A physically constrained dataset is constructed by sampling of some critical variables relevant to system. The QGHNN is trained to learn the nonlinear relationship between device parameters and the dual objectives of readout (separation) fidelity and Grover success probability. Gradient-based optimization is then carried out directly in parameter space using the trained network, yielding operating points that simultaneously improve measurement distinguishability and Grover algorithm accuracy. Simulation results demonstrate that the readout separation fidelity exceeds 99.4%, while the Grover success probability reaches approximately 86%, and this is comparable with the accuracy achieved by IBM Q5 Tenerife processor. Finally, the optimized parameters are used to implement the quantum circuit layout in Qiskit Metal, and their validity is further confirmed through EPR-based certification.

•Sep 23, 2026•0 citations
Abstract A new technique was developed to generate the dynamical quantum gates, depend on the ferromagnetism and antiferromagnetism phenomena in the superconducting flux qubits system at the same interaction time. According to the dynamical controls techniques of such gates, we invoke and synthesize a new algorithm called the dynamical quantum search algorithm. The Grover algorithm was obtained at a specified time for the current algorithm. This algorithm was distinguished by accuracy in obtaining high probability of finding any marked state in a shorter time compared with Grover algorithm time. The algorithm performance was improved with respect to different values of the dynamical controls.
We invoke an efficient search algorithms as a key challenge in multi-qubit quantum systems. An original algorithm called dynamical quantum search algorithm from which Grover algorithm is obtained at a specified time is presented. This algorithm is distinguished by accuracy in obtaining high probability of finding any marked state in a shorter time than Grover algorithm time. The algorithm performance can be improved with respect to the different values of the controlled phase. A new technique is used to generate the dynamical quantum gates in the presence of dissipation effect that helps in implementing the current algorithm.
In order to improve the searching efficiency of the Grover algorithm,a new quantum search algorithm was presented based on the Grover algorithm.This quantum search algorithm makes full use of the structural information of states,and spin quantum gates are designed in light of different initialized quantum states and searched ground states,then the new quantum gates are used to spin iteration.The research shows that compared with the Grover algorithm,the presented algorithm decreases iteration times.The feasibility and validity of this algorithm are verified through practical examples.
Abstract The conventional technique for controlling the states of individual qubits and quantum registers is based on the use of high-frequency modulated pulses whose carrier frequency is close to the transition frequency between the ground states of “artificial atoms” and “molecules” (the Rabi technique). In this paper, an alternative concept for controlling superconducting qubits is developed that is based on the idea of fast excitation of a quantum system by solitary unmodulated pulses. The formation of entangled Bell states in a two-qubit superconducting register under the action of field pulses obtained by rapid single flux quantum (RSFQ) devices is demonstrated by numerical simulation. The tomography of quantum states is performed by solving the density matrix equation. It is shown that the technique of “unipolar pulses” allows one to speed up the formation of entangled states (at picosecond times) with a fidelity of 95–98%. The execution of the basic quantum algorithms is demonstrated: the Deutsch–Jozsa algorithm with an accuracy of more than 98% and Grover’s algorithm with an accuracy of 93%.
Grover's quantum search algorithm is analyzed for the case in which the initial state is an arbitrary pure quantum state $|\ensuremath{\varphi}〉$ of n qubits. It is shown that the optimal time to perform the measurement is independent of $|\ensuremath{\varphi}〉,$ namely, it is identical to the optimal time in the original algorithm in which $|\ensuremath{\varphi}〉=|0〉,$ with the same number of marked states, r. The probability of success Ps{P}_{\mathrm{s}}Ps​ is obtained in terms of the amplitudes of the state $|\ensuremath{\varphi}〉$ and is shown to be independent of r. A class of states, which includes fixed points and cycles of the Grover iteration operator, is identified. The relevance of these results in the context of using the success probability as an entanglement measure is discussed. In particular, the Groverian entanglement measure, previously limited to a single marked state, is generalized to the case of several marked states.
We propose a potentially practical scheme for realization of an n-qubit (n>2) conditional phase flip (CPF) gate and implementation of Grover's search algorithm in an ion-trap system. We demonstrate, both analytically and numerically, that our scheme could be achieved efficiently to find a marked state with high fidelity and high success probability. We also show the merits of the proposal that the increase of the ion number can improve the fidelity and success probability of the CPF gate. The required operations for a Grover search are very close to the capabilities of current ion-trap techniques.
Abstract A hybrid physics–machine-learning framework is introduced for the joint optimization of separate fidelity and Grover algorithm performance in superconducting quantum processors. The method combines a Hamiltonian-based open-quantum-system model of a two-qubit architecture coupled through a bus resonator with a QGHNN. Readout performance is evaluated via the Lindblad master-equation simulation of the dispersive measurement process, in which state-dependent resonator dynamics are mapped to realistic I/Q distributions and classified to estimate single-shot measurement fidelity. In parallel, algorithmic performance is assessed by simulating a two-qubit Grover search circuit in the presence of dissipation and dephasing, using effective cross-Kerr interactions derived from the underlying circuit parameters. A physically constrained dataset is constructed by sampling of some critical variables relevant to system. The QGHNN is trained to learn the nonlinear relationship between device parameters and the dual objectives of readout (separation) fidelity and Grover success probability. Gradient-based optimization is then carried out directly in parameter space using the trained network, yielding operating points that simultaneously improve measurement distinguishability and Grover algorithm accuracy. Simulation results demonstrate that the readout separation fidelity exceeds 99.4%, while the Grover success probability reaches approximately 86%, and this is comparable with the accuracy achieved by IBM Q5 Tenerife processor. Finally, the optimized parameters are used to implement the quantum circuit layout in Qiskit Metal, and their validity is further confirmed through EPR-based certification.