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Related papers: Nested composite NOT gates for quantum computation

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Composite pulses --- sequences of pulses with well defined relative phases --- are an efficient, robust and flexible technique for coherent control of quantum systems. Composite sequences can compensate a variety of experimental errors in…

Quantum Physics · Physics 2019-08-21 Boyan T. Torosov , Nikolay V. Vitanov

We design composite controlled-phase gates, which compensate errors in the phase of a single gate. The errors can be of various nature, such as relative, absolute or both. We present composite sequences which are robust to relative errors…

Quantum Physics · Physics 2015-09-02 Svetoslav S. Ivanov , Nikolay V. Vitanov

We offer an alternative to the conventional network formulation of quantum computing. We advance the analog approach to quantum logic gate/circuit construction. As an illustration, we consider the spatially extended NOT gate as the first…

Quantum Physics · Physics 2014-11-18 Dima Mozyrsky , Vladimir Privman , Steven P. Hotaling

We present a systematic method for constructing universal composite phase gates with a continuously tunable target phase. Using a general Cayley--Klein parametrization of the single-pulse propagator, we design gates from an even number of…

Quantum Physics · Physics 2026-01-21 Peter Chernev , Mouhamad Al-Mahmoud , Andon A. Rangelov

How to effectively construct robust quantum gates for time-varying noise is a very important but still outstanding problem. Here we develop a systematic method to find pulses for quantum gate operations robust against both low- and…

Quantum Physics · Physics 2017-08-22 Chia-Hsien Huang , Hsi-Sheng Goan

Here we describe a simple mechanical procedure for compiling a quantum gate network into the natural gates (pulses and delays) for an Ising quantum computer. The aim is not necessarily to generate the most efficient pulse sequence, but…

Quantum Physics · Physics 2007-05-23 M. D. Bowdrey , J. A. Jones , E. Knill , R. Laflamme

Explicit controlled-NOT gate sequences between two qubits of different types are presented in view of applications for large-scale quantum computation. Here, the building blocks for such composite systems are qubits based on the…

Quantum Physics · Physics 2019-11-14 E. Ferraro , M. Fanciulli , M. De Michielis

Composite pulse segmentation has emerged as a promising error mitigation technique for a wide range of physical systems. In recent years, composite schemes were applied as mitigation strategies for quantum information processing and quantum…

Quantum Physics · Physics 2023-08-21 Ido Kaplan , Haim Suchowski , Yaron Oz

A quantum computer based on an asymmetric coupled dot system has been proposed and shown to operate as the controlled-NOT-gate. The basic idea is (1) the electron is localized in one of the asymmetric coupled dots. (2)The electron transfer…

Quantum Physics · Physics 2008-12-18 Tetsufumi Tanamoto

Systematic errors in quantum operations can be the dominating source of imperfection in achieving control over quantum systems. This problem, which has been well studied in nuclear magnetic resonance, can be addressed by replacing single…

Quantum Physics · Physics 2007-05-23 Kenneth Brown , Aram Harrow , Isaac Chuang

A quantum circuit is generalized to a nonunitary one whose constituents are nonunitary gates operated by quantum measurement. It is shown that a specific type of one-qubit nonunitary gates, the controlled-NOT gate, as well as all one-qubit…

Quantum Physics · Physics 2011-01-11 Hiroaki Terashima , Masahito Ueda

We briefly describe the use of GRAPE pulses to implement quantum logic gates in NMR quantum computers, and discuss a range of simple extensions to the core technique. We then consider a range of difficulties which can arise in practical…

Quantum Physics · Physics 2015-06-04 B. Rowland , J. A. Jones

Postselected quantum computation is distinguished from regular quantum computation by accepting the output only if measurement outcomes satisfy predetermined conditions. The output must be accepted with nonzero probability. Methods for…

Quantum Physics · Physics 2007-05-23 E. Knill

A clever choice and design of gate sets can reduce the depth of a quantum circuit, and can improve the quality of the solution one obtains from a quantum algorithm. This is especially important for near-term quantum computers that suffer…

Quantum Physics · Physics 2025-07-08 Madhav Mohan , Julius de Hond , Servaas Kokkelmans

We introduce a novel quantum control method for superconducting transmon qubits that substantially outperforms conventional techniques in precision and robustness against coherent errors. Our approach leverages composite pulses (CP) to…

Quantum Physics · Physics 2025-06-10 Hristo G. Tonchev , Boyan T. Torosov , Nikolay V. Vitanov

The Hamiltonian control of n qubits requires precision control of both the strength and timing of interactions. Compensation pulses relax the precision requirements by reducing unknown but systematic errors. Using composite pulse techniques…

Quantum Physics · Physics 2015-05-13 Yu Tomita , J. True Merrill , Kenneth R. Brown

Systematic control errors remain a primary obstacle to realizing high-fidelity single-qubit gates. We introduce composite pulse sequences that implement X and Hadamard gates while simultaneously compensating amplitude (Rabi-frequency),…

Quantum Physics · Physics 2026-05-01 Hristo G. Tonchev , Nikolay V. Vitanov

There are well-known protocols for performing CNOT quantum logic with qubits coupled by particular high-symmetry (Ising or Heisenberg) interactions. However, many architectures being considered for quantum computation involve qubits or…

Quantum Physics · Physics 2015-05-13 Michael R. Geller , Emily J. Pritchett , Andrei Galiautdinov , John M. Martinis

Parametrized gate circuits are used in plentiful applications in the current NISQ era of quantum computing. These parametrized gates are chiefly implemented using analytically found pulse protocols, often yielding suboptimal gate times, and…

Quantum Physics · Physics 2025-04-10 Robert de Keijzer , Jurgen Snijders , André Carvalho , Servaas Kokkelmans

Constructing a set of universal quantum gates is a fundamental task for quantum computation. The existence of noises, disturbances and fluctuations is unavoidable during the process of implementing quantum gates for most practical quantum…

Quantum Physics · Physics 2016-10-28 Daoyi Dong , Chengzhi Wu , Chunlin Chen , Bo Qi , Ian R. Petersen , Franco Nori