English
Related papers

Related papers: Optimal control of molecular spin qudits

200 papers

Electron spins confined in quantum dots are an attractive system to realize high-fidelity qubits owing to their long coherence time. With the prolonged spin coherence time, however, the control fidelity can be limited by systematic errors…

Mesoscale and Nanoscale Physics · Physics 2018-10-30 K. Takeda , J. Yoneda , T. Otsuka , T. Nakajima , M. R. Delbecq , G. Allison , Y. Hoshi , N. Usami , K. M. Itoh , S. Oda , T. Kodera , S. Tarucha

We theoretically investigate electron spin operations driven by applied electric fields in a semiconductor double quantum dot (DQD). Our model describes a DQD formed in semiconductor nanowire with longitudinal potential modulated by local…

We employ optimal control theory to design optimized quantum gates for solid-state qubits subject to decoherence. At the example of a gate-controlled semiconductor quantum dot molecule we demonstrate that decoherence due to phonon couplings…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Ulrich Hohenester

We present a combined analytical and numerical investigation to show how an optimal control field can be designed to generate maximum field-free orientation of molecules for three populated rotational states. Based on a model involving pure…

Quantum Physics · Physics 2021-07-28 Qian-Qian Hong , Li-Bao Fan , Chuan-Cun Shu , Niels E. Henriksen

We propose a method for quantum computation which uses control of spin-orbit coupling in a linear array of single electron quantum dots. Quantum gates are carried out by pulsing the exchange interaction between neighboring electron spins,…

Quantum Physics · Physics 2009-11-10 D. Stepanenko , N. E. Bonesteel

We describe a method for improving coherent control through the use of detailed knowledge of the system's Hamiltonian. Precise unitary transformations were obtained by strongly modulating the system's dynamics to average out unwanted…

Optimal control techniques provide a means to tailor the control pulses required to generate customized quantum gates, which helps to improve the resilience of quantum simulations to gate errors and device noise. However, the significant…

Quantum control allows a wide range of quantum operations employed in molecular physics, nuclear magnetic resonance and quantum information processing. Thanks to the existing microelectronics industry, semiconducting qubits, where quantum…

Quantum Physics · Physics 2024-12-05 Jia-Ao Peng , Chu-Dan Qiu , Wen-Long Ma , Jun-Wei Luo

The effective use of current Noisy Intermediate-Scale Quantum (NISQ) devices is often limited by the noise which is caused by interaction with the environment and affects the fidelity of quantum gates. In transmon qubit systems, the quantum…

Quantum Physics · Physics 2022-09-05 Elisha Siddiqui Matekole , Yao-Lung L. Fang , Meifeng Lin

We propose a methodology to design optimal pulses for achieving quantum optimal control on molecular systems. Our approach constrains pulse shapes to linear combinations of a fixed number of experimentally relevant pulse functions. Quantum…

Quantum Physics · Physics 2015-10-28 Ruben D. Guerrero , Carlos A. Arango , Andres Reyes

Optimization of the fidelity of control operations is of critical importance in the pursuit of fault-tolerant quantum computation. We apply optimal control techniques to demonstrate that a single drive via the cavity in circuit quantum…

Quantum Physics · Physics 2017-04-20 Joseph L. Allen , Robert Kosut , Jaewoo Joo , Peter Leek , Eran Ginossar

We show that several qubits can be integrated in a single magnetic ion, using its internal electronic spin states with energies tuned by a suitably chosen molecular environment. This approach is illustrated with a nearly-isotropic Gd(III)…

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

One fundamental requirement for quantum computation is to perform universal manipulations of quantum bits at rates much faster than the qubit's rate of decoherence. Recently, fast gate operations have been demonstrated in logical spin…

Mesoscale and Nanoscale Physics · Physics 2010-09-28 Sandra Foletti , Hendrik Bluhm , Diana Mahalu , Vladimir Umansky , Amir Yacoby

Solid state spin qubits are promising candidates for quantum information processing, but controlled interactions and entanglement in large, multi-qubit systems are currently difficult to achieve. We describe a method for programmable…

Optimal control can be used to significantly improve multi-qubit gates in quantum information processing hardware architectures based on superconducting circuit quantum electrodynamics. We apply this approach not only to dispersive gates of…

Quantum Physics · Physics 2015-05-14 R. Fisher , F. Helmer , S. J. Glaser , F. Marquardt , T. Schulte-Herbrueggen

The lack of a direct map between control fields and desired control objectives poses a significant challenge in applying quantum control theory to quantum technologies. Here, we propose an analytical framework to precisely control a limited…

Quantum Physics · Physics 2025-03-05 Qian-Qian Hong , Daoyi Dong , Niels E. Henriksen , Franco Nori , Jun He , Chuan-Cun Shu

In a Josephson phase qubit the coherent manipulations of the computational states are achieved by modulating an applied ac current, typically in the microwave range. In this work we show that it is possible to find optimal modulations of…

Mesoscale and Nanoscale Physics · Physics 2010-09-08 Shabnam Safaei , Simone Montangero , Fabio Taddei , Rosario Fazio

We present a theoretical framework for universal single-qutrit control in asymmetric-top molecules, advancing molecular quantum information processing. In this approach, the qutrit is encoded in three rotational eigenstates, with an…

Quantum Physics · Physics 2026-05-06 Qian-Qian Hong , Zhi-Jian Zheng , Zhe-Jun Zhang , Xin-Xia Jian , Chuan-Cun Shu

We study the ability to control d-dimensional quantum systems (qudits) encoded in the hyperfine spin of alkali-metal atoms through the application of radio- and microwave-frequency magnetic fields in the presence of inhomogeneities in…

Quantum Physics · Physics 2015-05-30 Brian E. Mischuck , Seth T. Merkel , Ivan H. Deutsch