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Related papers: Ultrahigh-fidelity composite quantum phase gates

200 papers

In this paper, we demonstrate that, by employing OpenPulse design kit for IBM superconducting quantum devices, the controlled-V gate (CV gate) can be implemented in about half the gate time to the controlled-X (CX or CNOT gate) and…

Quantum Physics · Physics 2025-01-29 Takahiko Satoh , Shun Oomura , Michihiko Sugawara , Naoki Yamamoto

Trapped ions are a well-studied and promising system for the realization of a scalable quantum computer. Faster quantum gates would greatly improve the applicability of such a system and allow for greater flexibility in the number of…

Quantum Physics · Physics 2019-07-24 D. Heinrich , M. Guggemos , M. Guevara-Bertsch , M. I. Hussain , C. F. Roos , R. Blatt

We address the problem of implementing high fidelity one-qubit operations subject to time dependent noise in the qubit energy splitting. We show with explicit numerical results that high fidelity bit flips and one-qubit NOT gates may be…

Quantum Physics · Physics 2009-11-11 Mikko Mottonen , Rogerio de Sousa , Jun Zhang , K. Birgitta Whaley

Twisted rapid passage is a type of non-adiabatic rapid passage that generates controllable quantum interference effects that were first observed experimentally in 2003. It is shown that twisted rapid passage sweeps can be used to implement…

Quantum Physics · Physics 2010-09-16 Ran Li , Frank Gaitan

We propose a simple formalism to design unitary gates robust against given systematic errors. This formalism generalizes our previous observation [Y. Kondo and M. Bando, J. Phys. Soc. Jpn. 80, 054002 (2011)] that vanishing dynamical phase…

Quantum Physics · Physics 2011-12-20 Tsubasa Ichikawa , Masamitsu Bando , Yasushi Kondo , Mikio Nakahara

Time-frequency Schmidt (TFS) modes of ultrafast quantum states are naturally compatible with high bit-rate integrated quantum communication networks. Thus they offer an attractive alternative for the realization of high dimensional quantum…

Superconducting qubit parameters drift on sub-second timescales, motivating calibration and benchmarking techniques that can be executed on millisecond timescales. We demonstrate an on-FPGA workflow that co-locates pulse generation, data…

We propose and validate on real quantum computing hardware a new method for extended two-qubit gate set design, replacing iterative, fine calibration with fast characterization of a small number of gate parameters which are then tracked and…

A Quantum Computer is a new type of computer which can solve problems such as factoring and database search very efficiently. The usefulness of a quantum computer is limited by the effect of two different types of errors, decoherence and…

Quantum Physics · Physics 2007-05-23 Kevin M. Obenland , Alvin M. Despain

Isolated spins in semiconductors provide a promising platform to explore quantum mechanical coherence and develop engineered quantum systems. Silicon has attracted great interest as a host material for developing spin qubits because of its…

Mesoscale and Nanoscale Physics · Physics 2015-10-29 Dohun Kim , D. R. Ward , C. B. Simmons , D. E. Savage , M. G. Lagally , Mark Friesen , S. N. Coppersmith , Mark A. Eriksson

The fault-tolerant operation of logical qubits is an important requirement for realizing a universal quantum computer. Spin qubits based on quantum dots have great potential to be scaled to large numbers because of their compatibility with…

Recent developments in engineering and algorithms have made real-world applications in quantum computing possible in the near future. Existing quantum programming languages and compilers use a quantum assembly language composed of 1- and…

The transmon, known for its fast operation time and the coherence time of tens of microseconds, is the most commonly used qubit for superconducting quantum processors. However, it is still necessary to enhance the coherence time and the…

Quantum Physics · Physics 2025-04-01 Jeongsoo Kang , Younghun Kwon

The creation of composite quantum gates that implement quantum response functions $\hat{U}(\theta)$ dependent on some parameter of interest $\theta$ is often more of an art than a science. Through inspired design, a sequence of $L$…

Quantum Physics · Physics 2018-02-02 Guang Hao Low , Theodore J. Yoder , Isaac L. Chuang

Efficient decompositions of multi-qubit gates are essential in NISQ applications, where the number of gates or the circuit depth is limited. This paper presents efficient decompositions of CCZ and CCCZ gates, typical multi-qubit gates,…

Quantum Physics · Physics 2021-09-28 Ken M. Nakanishi , Takahiko Satoh , Synge Todo

Fault-tolerant quantum computers compose elements of a discrete gate set in order to approximate a target unitary. The problem of minimising the number of gates is known as gate-synthesis. The approximation error is a form of coherent…

Quantum Physics · Physics 2017-04-12 Earl Campbell

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

We study how dynamical decoupling (DD) pulse sequences can improve the reliability of quantum computers. We prove upper bounds on the accuracy of DD-protected quantum gates and derive sufficient conditions for DD-protected gates to…

Quantum Physics · Physics 2011-07-19 Hui Khoon Ng , Daniel A. Lidar , John Preskill

We present a few-parameter ansatz for pulses to implement a broad set of simultaneous single-qubit rotations in frequency-crowded multilevel systems. Specifically, we consider a system of two qutrits whose working and leakage transitions…

Quantum Physics · Physics 2016-01-18 L. S. Theis , F. Motzoi , F. K. Wilhelm

Numerically we simulate the effect of optimized coherent control pulses with a finite duration on a qubit in a bath of spins. The pulses of finite duration are compared with ideal instantaneous pulses. In particular, we show that properly…

Quantum Physics · Physics 2008-08-26 P. Karbach , S. Pasini , G. S. Uhrig