English
Related papers

Related papers: On photonic controlled phase gates

200 papers

We examine three possible implementations of non-deterministic linear optical cnot gates with a view to an in-principle demonstration in the near future. To this end we consider demonstrating the gates using currently available sources such…

Quantum Physics · Physics 2009-11-10 A. Gilchrist , W. J. Munro , A. G. White

The information obtained from the operation of a quantum gate on only two complementary sets of input states is sufficient to estimate the quantum process fidelity of the gate. In the case of entangling gates, these conditions can be used…

Quantum Physics · Physics 2017-08-23 Holger F. Hofmann , Ryo Okamoto , Shigeki Takeuchi

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

This is a brief overview of quantum holonomies in the context of quantum computation. We choose an adequate set of quantum logic gates, namely, a phase gate, the Hadamard gate, and a conditional-phase gate and show how they can be…

Quantum Physics · Physics 2007-05-23 Marie Ericsson

The controlled-NOT gate and controlled square-root NOT gate play an important role in quantum algorithm. This article reports the experimental results of these two universal quantum logic gates (controlled square-root NOT gate and…

Quantum Physics · Physics 2007-05-23 Daxiu Wei , Xiaodong Yang , Jun Luo , Xianping Sun , Xizhi Zeng , Maili Liu , Shangwu Ding

A crucial building block for quantum information processing with trapped ions is a controlled-NOT quantum gate. In this paper, two different sequences of laser pulses implementing such a gate operation are analyzed using quantum process…

Quantum Physics · Physics 2009-01-15 M. Riebe , K. Kim , P. Schindler , T. Monz , P. O. Schmidt , T. K. Koerber , W. Haensel , H. Haeffner , C. F. Roos , R. Blatt

One of the main advantages of an optical approach to quantum computing is the fact that optical fibers can be used to connect the logic and memory devices to form useful circuits, in analogy with the wires of a conventional computer. Here…

Quantum Physics · Physics 2016-09-08 T. B. Pittman , B. C Jacobs , J. D. Franson

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 present a way to realize a multiplex-controlled phase gate of n-1 control qubits simultaneously controlling one target qubit, with n qubits distributed in n different cavities. This multiqubit gate is implemented by using n qutrits…

Quantum Physics · Physics 2019-10-21 Biaoliang Ye , Zhen-Fei Zheng , Chui-Ping Yang

We introduce a modular-value two-qubit gate and explore its advantages in experimentally-limited situations. The gate is defined such that the final state of a target qubit is fully controlled by a pre- and post-selection procedure in a…

Quantum Physics · Physics 2017-02-28 Julián Martínez-Rincón

We design linear optics multiqubit quantum logic gates. We assume the traditional encoding of a qubit onto state of a single photon in two modes (e.g. spatial or polarization). We suggest schemes allowing direct probabilistic realization of…

Quantum Physics · Physics 2009-11-13 Jaromir Fiurasek

Quantum logic gates can perform calculations much more efficiently than their classical counterparts. However, the level of control needed to obtain a reliable quantum operation is correspondingly higher. In order to evaluate the…

Quantum Physics · Physics 2009-11-13 Holger F. Hofmann , Ryo Okamoto , Shigeki Takeuchi

Deterministic photon-photon gates enable the controlled generation of entanglement between mobile carriers of quantum information. Such gates have thus far been exclusively realized in the optical domain and by relying on post-selection.…

The controlled-not gate and the single qubit gates are considered elementary gates in quantum computing. It is natural to ask how many such elementary gates are needed to implement more elaborate gates or circuits. Recall that a…

Quantum Physics · Physics 2007-05-23 Guang Song , Andreas Klappenecker

High-fidelity two-qubit entangling gates are essential building blocks for fault-tolerant quantum computers. Over the past decade, tremendous efforts have been made to develop scalable high-fidelity two-qubit gates with superconducting…

Quantum Physics · Physics 2021-11-12 Ji Chu , Fei Yan

Cat-state qubits (qubits encoded with cat states) have recently drawn intensive attention due to their enhanced life times with quantum error correction. We here propose a method to implement a universal controlled-phase gate of two…

Quantum Physics · Physics 2017-11-22 Yu Zhang , Xiong Zhao , Li Yu , Qi-Ping Su , Chui-Ping Yang

For quantum computation using photons, performing deterministic quantum gate operations is a challenge due to the probabilistic nature of the photon-photon interaction. Encoding qubits in multiple degrees-of-freedom of photons and…

Quantum Physics · Physics 2025-08-28 Kanad Sengupta , S. P. Dinesh , K. Muhammed Shafi , Soumya Asokan , C. M. Chandrashekar

Quantum logic gates must perform properly when operating on their standard input basis states, as well as when operating on complex superpositions of these states. Experiments using superconducting qubits have validated the truth table for…

We construct a generalized controlled phased gate entangler for a multi-qubit state based on the geometrical structure of quantum systems. We also investigate relation between the generalized controlled phase construction of a quantum gate…

Quantum Physics · Physics 2009-12-21 Hoshang Heydari

Optimal implementation of quantum gates is crucial for designing a quantum computer. We consider the matrix representation of an arbitrary multiqubit gate. By ordering the basis vectors using the Gray code, we construct the quantum circuit…

Quantum Physics · Physics 2007-05-23 Juha J. Vartiainen , Mikko Mottonen , Martti M. Salomaa