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Related papers: Gradient Ascent Pulse Engineering with Feedback

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Designing multi-qubit quantum logic gates with experimental constraints is an important problem in quantum computing. Here, we develop a new quantum optimal control algorithm for finding unitary transformations with constraints on the…

Quantum Physics · Physics 2025-08-25 Dylan Lewis , Roeland Wiersema , Sougato Bose

The experimental optimization of a two-qubit controlled-Z (CZ) gate is realized following two different data-driven gradient ascent pulse engineering (GRAPE) protocols in the aim of optimizing the gate operator and the output quantum state,…

High-fidelity control of quantum systems is essential for scalable quantum technologies. We introduce a shooting-based method which yields smooth control pulses designed to implement gates on discrete quantum systems, and demonstrate its…

Feedback control in open quantum dynamics is crucial for the advancement of various coherent platforms. However, currently only a handful of feedback master equations exist in the literature, which are restricted to specific types of…

Quantum Physics · Physics 2025-12-10 Alberto J. B. Rosal , Patrick P. Potts , Gabriel T. Landi

The ability to control quantum systems is necessary for many applications of quantum technologies ranging from gate generation in quantum computation to NMR and laser control of chemical reactions. In many practical situations, the…

Quantum Physics · Physics 2024-03-21 Alexander Pechen

We realize arbitrary waveform-based control of spin-selective recombination reactions of radical pairs in the low magnetic field regime. To this end, we extend the Gradient Ascent Pulse Engineering (GRAPE) paradigm to allow for optimizing…

Chemical Physics · Physics 2024-06-21 Farhan T. Chowdhury , Matt C. J. Denton , Daniel C. Bonser , Daniel R. Kattnig

Bosonic codes allow the encoding of a logical qubit in a single component device, utilizing the infinitely large Hilbert space of a harmonic oscillator. In particular, the Gottesman-Kitaev-Preskill code has recently been demonstrated to be…

Quantum Physics · Physics 2025-01-22 Matteo Puviani , Sangkha Borah , Remmy Zen , Jan Olle , Florian Marquardt

The development of efficient algorithms that generate robust quantum controls is crucial for the realization of quantum technologies. The commonly used gradient-based optimization algorithms are limited by their sensitivity to the initial…

Quantum Physics · Physics 2021-12-03 M. Harshanth Ram , V. R. Krithika , Priya Batra , T. S. Mahesh

Pulses to steer the time evolution of quantum systems can be designed with optimal control theory. In most cases it is the coherent processes that can be controlled and one optimizes the time evolution towards a target unitary process,…

Quantum Physics · Physics 2015-06-22 Daniel J. Egger , Frank K. Wilhelm

In real-world applications of reinforcement learning (RL), noise from inherent stochasticity of environments is inevitable. However, current policy evaluation algorithms, which plays a key role in many RL algorithms, are either prone to…

Machine Learning · Computer Science 2019-06-19 Tadashi Kozuno , Dongqi Han , Kenji Doya

We consider subspace transfer within the time-dependent one-dimensional quantum transverse Ising model, with random nearest-neighbor interactions and a transverse field. We run numerical simulations using a variational approach and the…

Quantum Physics · Physics 2025-04-08 C. Whitty , E. Ya. Sherman , Xi Chen , Yue Ban

We describe a scheme for quantum error correction that employs feedback and weak measurement rather than the standard tools of projective measurement and fast controlled unitary gates. The advantage of this scheme over previous protocols…

Quantum Physics · Physics 2009-11-10 Mohan Sarovar , Charlene Ahn , Kurt Jacobs , Gerard J. Milburn

Quantum control aims to manipulate quantum systems toward specific quantum states or desired operations. Designing highly accurate and effective control steps is vitally important to various quantum applications, including energy…

Quantum Physics · Physics 2023-01-11 Xinyu Fei , Lucas T. Brady , Jeffrey Larson , Sven Leyffer , Siqian Shen

We study the impact of static disorder on a globally-controlled superconducting quantum computing architecture based on a quasi-two-dimensional ladder geometry [R. Menta et al., Phys. Rev. Research 7, L012065 (2025)]. Specifically, we…

We introduce the MAGICARP algorithm, a numerical optimization method for quantum optimal control problems that combines the structure provided by Pontryagin's Maximum Principle (PMP) and the robustness of gradient ascent techniques, such as…

The control of individual quantum systems is now a reality in a variety of physical settings. Feedback control is an important class of control methods because of its ability to reduce the effects of noise. In this review we give an…

Quantum Physics · Physics 2017-08-01 Jing Zhang , Yu-xi Liu , Re-Bing Wu , Kurt Jacobs , Franco Nori

Developments over the last two decades have opened the path towards quantum technologies in many quantum systems, such as cold atoms, trapped ions, cavity-quantum electrodynamics (QED), and circuit-QED. However the fragility of quantum…

Quantum Physics · Physics 2020-09-17 Shay Hacohen-Gourgy , Leigh S. Martin

We study quantum control techniques, specifically Adiabatic Rapid Passage (ARP) and Gradient Ascent Pulse Engineering (GRAPE), for transferring atoms trapped in an optical lattice between different vibrational states. We compare them with…

We study optimal quantum control of the dynamics of trapped Bose-Einstein condensates: The targets are to split a condensate, residing initially in a single well, into a double well, without inducing excitation; and to excite a condensate…

Quantum Physics · Physics 2014-10-23 Georg Jäger , Daniel Reich , Michael H. Goerz , Christiane P. Koch , Ulrich Hohenester

In this paper, we propose a scheme to eliminate the influence of noises on system dynamics, by means of a sequential unsharp measurements and unitary feedback operations. The unsharp measurements are carried out periodically during system…

Quantum Physics · Physics 2018-09-19 Du Ran , Ye-Hong Chen , Zhi-Cheng Shi , Zhen-Biao Yang , Jie Song , Yan Xia