English
Related papers

Related papers: Control optimization for parametric hamiltonians b…

200 papers

Parity-time ($PT$)-symmetric Hamiltonians exhibit non-unitary dynamical evolution while maintaining real spectra, and offer unique approaches to quantum sensing and entanglement generation. Here we present a method for simulating the…

Quantum Physics · Physics 2026-01-15 Maryam Abbasi , Koray Aydogan , Anthony W. Schlimgen , Kade Head-Marsden

We address the problem of simulating pair-interaction Hamiltonians in n node quantum networks where the subsystems have arbitrary, possibly different, dimensions. We show that any pair-interaction can be used to simulate any other by…

Quantum Physics · Physics 2023-11-27 Pawel Wocjan , Martin Roetteler , Dominik Janzing , Thomas Beth

Analog quantum simulators can directly emulate time-dependent Hamiltonian dynamics, enabling the exploration of diverse physical phenomena such as phase transitions, quench dynamics, and non-equilibrium processes. Realizing accurate analog…

Quantum Physics · Physics 2025-12-04 Yulong Dong , Christopher Kang , Murphy Yuezhen Niu

Quantum computers based on cold-atom arrays offer long-lived qubits with programmable connectivity, yet their progress toward fault-tolerant operation is limited by the relatively low fidelity of site-selective local control. We introduce…

Quantum Physics · Physics 2025-11-18 Sanghyo Park , Seuk Lee , Keunyoung Lee , Minhyeok Kim , Donggyu Kim

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…

Current quantum devices execute specific tasks that are hard for classical computers and have the potential to solve problems such as quantum simulation of material science and chemistry, even without error correction. For practical…

Quantum Physics · Physics 2022-04-29 V. M. Bastidas , T. Haug , C. Gravel , L. -C. Kwek , W. J. Munro , Kae Nemoto

In this paper, we introduce a neural network to generate optimal control pulses for general single-qubit quantum logic gates, within a Nuclear Magnetic Resonance (NMR) quantum computer. By utilizing a neural network, we can efficiently…

Hamiltonian encoding was introduced as a technique for revealing the mechanism of controlled quantum systems. It does so by decomposing the evolution into pathways between the computational basis states, where each pathway has an associated…

Quantum Physics · Physics 2025-06-09 Michael Kasprzak , Gaurav Bhole , Herschel Rabitz

The utility of near-term quantum computers and simulators is likely to rely upon software-hardware co-design, with error-aware algorithms and protocols optimized for the platforms they are run on. Here, we show how knowledge of noise in a…

Quantum Physics · Physics 2024-09-04 Kushal Seetharam , Dries Sels , Eugene Demler

In conventional variational quantum eigensolvers (VQEs), trial states are prepared by applying series of parameterized gates to a reference state, with the gate parameters being varied to minimize the energy of the target system.…

Quantum Physics · Physics 2025-02-17 Kyle M Sherbert , Hisham Amer , Sophia E Economou , Edwin Barnes , Nicholas J Mayhall

We present an iterative optimal control method of quantum systems, aimed at an implementation of a desired operation with optimal fidelity. The update step of the method is based on the linear response of the fidelity to the control…

Quantum Physics · Physics 2025-02-06 Nicolas Heimann , Lukas Broers , Ludwig Mathey

The quantum circuit model is the de-facto way of designing quantum algorithms. Yet any level of abstraction away from the underlying hardware incurs overhead. In the era of near-term, noisy, intermediate-scale quantum (NISQ) hardware with…

Quantum Physics · Physics 2021-08-27 Laura Clinton , Johannes Bausch , Toby Cubitt

The control of quantum dynamics via specially tailored laser pulses is a long-standing goal in physics and chemistry. Partly, this dream has come true, as sophisticated pulse shaping experiments allow to coherently control product ratios of…

Quantum Physics · Physics 2007-07-16 J. Werschnik , E. K. U. Gross

We propose a simple but versatile protocol to engineer time-dependent Hamiltonians inversely for geometric quantum computation. By utilizing SU(2) transformation, a speedup goal on gate operation is achieved with more freedom to design the…

Quantum Physics · Physics 2021-03-31 Jian-jian Cheng , Lin Zhang

Fast tuning of the transition frequency of superconducting qubits using magnetic flux is essential, for example, for realizing high-fidelity two-qubit gates with low leakage or for reducing errors in dispersive qubit readout. To apply…

The optimal quantum control theory is employed to determine electric pulses capable of producing quantum gates with high fidelity (higher than 0.9997). Particularly, these quantum gates were chosen to perform the permutation algorithm (Z.…

Quantum Physics · Physics 2018-03-28 C. M. Rivera-Ruiz , E. F. de Lima , F. F. Fanchini , V. Lopez-Richard , L. K. Castelano

Quantum optimal control methods are widely used to design experimental control pulses such as laser amplitudes, phases, or detunings, that implement a target unitary evolution. In practice, what makes a pulse "good" depends not only on its…

Quantum Physics · Physics 2026-04-29 Dylan Lewis , Roeland Wiersema

Simulations of quantum chemistry and quantum materials are believed to be among the most important potential applications of quantum information processors, but realizing practical quantum advantage for such problems is challenging. Here,…

We describe a simple method for simulating time-independent Hamiltonian $H$ that could be decomposed as $H = \sum_{i=1}^m H_i$ where each $H_i$ can be efficiently simulated. Approaches relying on product formula generally work by splitting…

Quantum Physics · Physics 2024-10-22 Nhat A. Nghiem

Unitary operations are the building blocks of quantum programs. Our task is to design effcient or optimal implementations of these unitary operations by employing the intrinsic physical resources of a given n-qubit system. The most common…

Quantum Physics · Physics 2007-05-23 Robert Zeier , Markus Grassl , Thomas Beth