English
Related papers

Related papers: Global Control Methods for GHZ State Generation on…

200 papers

High-fidelity quantum operations are a key requirement for fault-tolerant quantum information processing. In electron spin resonance, manipulation of the quantum spin is usually achieved with time-dependent microwave fields. In contrast to…

A protocol is discussed for preparing a spin chain in a generic many-body state in the asymptotic limit of tailored non-unitary dynamics. The dynamics require the spectral resolution of the target state, optimized coherent pulses,…

Quantum state transfer through a spin chain via adiabatic dark passage is proposed. This technique is robust against control field fluctuations and unwanted environmental coupling of intermediate spins. Our method can be applied to spin…

Quantum Physics · Physics 2008-08-04 Toshio Ohshima , Artur Ekert , Daniel K. L. Oi , Dagomir Kaslizowski , L. C. Kwek

For a double quantum dot (DQD) system, here we propose alternative ultrafast manipulate approach: Lyapunov control method, to transfer the state from R to L on the picosecond scale, orders of magnitude faster and transfer probability higher…

Quantum Physics · Physics 2015-11-12 Shuang Cong , Ming-yong Gao , Long-zhen Hu , Guo-ping Guo , Gang Cao , Guang-can Guo

Quantum state control is a fundamental tool for quantum technologies. In this work, we propose and analyze the use of quantum optimal control to exploit the dipolar interaction of ultracold atoms on a lattice ring, focusing on the…

The framework of quantum invariants is an elegant generalization of adiabatic quantum control to control fields that do not need to change slowly. Due to the unavailability of invariants for systems with more than one spatial dimension, the…

Quantum Physics · Physics 2021-03-17 Selwyn Simsek , Florian Mintert

State preparation plays a pivotal role in numerous quantum algorithms, including quantum phase estimation. This paper extends and benchmarks counterdiabatic driving protocols across three one-dimensional spin systems characterized by phase…

Quantum Physics · Physics 2024-03-11 Francesco Pio Barone , Oriel Kiss , Michele Grossi , Sofia Vallecorsa , Antonio Mandarino

The critical quantum metrology, which exploits the quantum phase transition for high precision measurement, has gained increasing attention recently. The critical quantum metrology with the continuous quantum phase transition, however, is…

Quantum Physics · Physics 2021-02-16 Ran Liu , Yu Chen , Min Jiang , Xiaodong Yang , Ze Wu , Yuchen Li , Haidong Yuan , Xinhua Peng , Jiangfeng Du

When a quantum system is driven adiabatically through a parametric cycle in a degenerate Hilbert space, the state would acquire a non-Abelian geometric phase, which is stable and forms the foundation for holonomic quantum computation (HQC).…

The convergence of closed quantum systems in the degenerate cases to the desired target state by using the quantum Lyapunov control based on the average value of an imaginary mechanical quantity is studied. On the basis of the existing…

Systems and Control · Computer Science 2018-08-10 Shuang Cong , Fangfang Meng , Sen Kuang

Universal quantum gates whose operation depends on the manipulation of the geometric phase of atomic systems are promising candidates for implementation of quantum computing. We propose a scheme inducing a non-trivial Aharonov-Anandan…

Quantum Physics · Physics 2025-04-16 Omar Morandi

We present a quantum optimal control protocol to generate highly spin-squeezed states in Rydberg atom arrays coupled via Ising-type van der Waals interactions. Using gradient-based optimization techniques, we construct time-dependent pulse…

Quantum Physics · Physics 2025-12-01 Edison S. Carrera , Harold Erbin , Grégoire Misguich

Unitary control and decoherence appear to be irreconcilable in quantum mechanics. When a quantum system interacts with an environment, control strategies usually fail due to decoherence. In this letter, we propose a time-optimal unitary…

Quantum Physics · Physics 2013-02-20 P. M. Poggi , F. C. Lombardo , D. A. Wisniacki

We analyze the control of the motion of a charged particle by means of an external electric field. The system is constrained to move along a given direction. The goal of the control is to change the speed of the particle in a fixed time…

Optimization and Control · Mathematics 2020-01-22 V. Martikyan , D. Guéry-Odelin , D. Sugny

We show that combining ideas from the fields of quantum invariants and of optimal control can be used to design optimal quantum control solutions without explicit reference to quantum states. The states are specified only implicitly in…

Quantum Physics · Physics 2025-11-05 Modesto Orozco-Ruiz , Nguyen H. Le , Florian Mintert

Quantum states that are symmetric under particle exchange play a crucial role in fields such as quantum metrology and quantum error correction. We use a variational circuit composed of global one-axis twisting and global rotations to…

Using the adiabatic perturbation theory of driven dynamics [Phys. Rev. A 78, 052508 (2008)] we design a hierarchy of quantum state preparation protocols that systematically increase the fidelity at very long driving times. We test these and…

Quantum Physics · Physics 2023-02-01 Felipe Matus , Jan Střeleček , Pavel Stránský , Pavel Cejnar

As a hybrid of techniques from open-loop and feedback control, Lyapunov control has the advantage that it is free from the measurement-induced decoherence but it includes the system's instantaneous message in the control loop. Often, the…

Quantum Physics · Physics 2015-05-27 X. X. Yi , S. L. Wu , Chunfeng Wu , X. L. Feng , C. H. Oh

Entangled states of two ions are realized by using an adiabatic process. Based on the proposal by Linington and Vitanov, we have generated Dicke states in optical qubits of two $^{40}$Ca$^+$ ions by applying frequency-chirped optical pulses…

Quantum Physics · Physics 2015-05-27 K. Toyoda , T. Watanabe , T. Kimura , S. Nomura , S. Haze , S. Urabe

We study reachable sets of open n-qubit quantum systems, whose coherent parts are under full unitary control, by adding as a further degree of incoherent control switchable Markovian noise on a single qubit. In particular, adding bang-bang…

Quantum Physics · Physics 2017-04-24 Ville Bergholm , F. K. Wilhelm , T. Schulte-Herbrueggen