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Related papers: From virtual Z gates to virtual Z pulses

200 papers

Quantum computing is currently limited by the cost of two-qubit entangling operations. In order to scale up quantum processors and achieve a quantum advantage, it is crucial to economize on the power requirement of two-qubit gates, make…

Single flux quantum pulses are a natural candidate for on-chip control of superconducting qubits. We show that they can drive high-fidelity single-qubit rotations---even in leaky transmon qubits---if the pulse sequence is suitably…

Quantum Physics · Physics 2016-09-07 Per J. Liebermann , Frank K. Wilhelm

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…

This work studies pulse based variational quantum algorithms (VQAs), which are designed to determine the ground state of a quantum mechanical system by combining classical and quantum hardware. In contrast to more standard gate based…

Quantum Physics · Physics 2023-02-01 Robert de Keijzer , Oliver Tse , Servaas Kokkelmans

Multi-controlled gates are essential primitives in quantum algorithms, yet implementing them via standard gate-level decompositions remains resource-intensive. We develop efficient pulse-level implementations of multi-controlled gates in…

Quantum Physics · Physics 2026-05-07 Minhyeok Kang , Taejin Kim , Jungsoo Hong , Joonsuk Huh

We present theoretical schemes for performing high-fidelity one- and two-qubit pulsed gates for a superconducting flux qubit. The "IBM qubit" consists of three Josephson junctions, three loops, and a superconducting transmission line.…

Quantum Physics · Physics 2008-03-19 Frederico Brito , David P. DiVincenzo , Roger H. Koch , Matthias Steffen

We demonstrate experimentally the usefulness of selective pulses in NMR to perform quantum computation. Three different techniques based on selective pulse excitations have been proposed to prepare a spin system in a pseudo-pure state. We…

Quantum Physics · Physics 2008-12-18 Kavita Dorai , Arvind , Anil Kumar

Quantum computers based on silicon are promising candidates for long term universal quantum computation due to the long coherence times of electron and nuclear spin states. Furthermore, the continuous progress of micro- and nano-…

Quantum Physics · Physics 2022-03-23 Davide Rei , Elena Ferraro , Marco De Michielis

We propose encoding multiple qubits inside ions in existing trapped-ion quantum computers to access more qubits and to simplify circuits implementing standard algorithms. By using such `virtual' qubits, some inter-ion gates can be replaced…

Most quantum processors requires pulse sequences for controlling quantum states. Here, we present an alternative algorithm for computing an optimal pulse sequence in order to perform a specific task, being an implementation of a quantum…

Quantum Physics · Physics 2020-05-27 John P. S. Peterson , Roberto S. Sarthour , Raymond Laflamme

Spin qubits are very valuable and scalable candidates in the area of quantum computation and simulation applications. In the last decades, they have been deeply investigated from a theoretical point of view and realized on the scale of few…

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

Quantum algorithm design usually assumes access to a perfect quantum computer with ideal properties like full connectivity, noise-freedom and arbitrarily long coherence time. In Noisy Intermediate-Scale Quantum (NISQ) devices, however, the…

Quantum Physics · Physics 2020-09-11 Xiangzhen Zhou , Sanjiang Li , Yuan Feng

Quantum computers provide a fundamentally new computing paradigm that promises to revolutionize our ability to solve broad classes of problems. Surprisingly, the basic mathematical structures of gate-based quantum computing, such as unitary…

Quantum Physics · Physics 2019-08-20 Brian R. La Cour , S. Andrew Lanham , Corey I. Ostrove

We present a native three-qubit entangling gate that exploits engineered interactions to realize control-control-target and control-target-target operations in a single coherent step. Unlike conventional decompositions into multiple…

Quantum Physics · Physics 2025-08-15 Xuexin Xu , Siyu Wang , Radhika Joshi , Rihan Hai , Mohammad H. Ansari

We investigate the possibility to achieve high-fidelity universal two-qubit gates by supplementing optimal tuning of individual qubits with dynamical decoupling (DD) of local 1/f noise. We consider simultaneous local pulse sequences applied…

Quantum Physics · Physics 2016-08-24 A. D'Arrigo , G. Falci , E. Paladino

The power of a quantum circuit is determined through the number of two-qubit entangling gates that can be performed within the coherence time of the system. In the absence of parallel quantum gate operations, this would make the quantum…

Quantum Physics · Physics 2021-05-26 Rozhin Yousefjani , Abolfazl Bayat

Building large-scale superconducting quantum computers requires two complimentary elements: scalable wiring techniques and multiplex architectures. In our previous work [B\'ejanin et al., Phys. Rev. Applied 6, 044010 (2016)], we have…

Quantum Physics · Physics 2022-11-02 J. H. Béjanin , C. T. Earnest , M. Mariantoni

We present a theoretical study of single-qubit operations by oscillatory fields on various semiconductor platforms. We explicitly show how to perform faster gate operations by going beyond the universally-used rotating wave approximation…

Mesoscale and Nanoscale Physics · Physics 2016-07-22 Yang Song , J. P. Kestner , Xin Wang , S. Das Sarma

Vigorous optimization of quantum gates has led to bipotent quantum architectures, where the optimized gates are available for some qubits but not for others. However, such gate-level improvements limit the application of user-side…

Quantum Physics · Physics 2023-08-21 Yanjun Ji , Kathrin F. Koenig , Ilia Polian

In this paper we apply the canonical decomposition of two qubit unitaries to find pulse schemes to control the proposed Kane quantum computer. We explicitly find pulse sequences for the CNOT, swap, square root of swap and controlled Z…

Quantum Physics · Physics 2009-11-10 Charles D. Hill , Hsi-Sheng Goan