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The stabiliser formalism plays a central role in quantum computing, error correction, and fault tolerance. Conversions between and verifications of different specifications of stabiliser states and Clifford gates are important components of…

Quantum Physics · Physics 2025-01-09 Nadish de Silva , Wilfred Salmon , Ming Yin

We have successfully used a fast electronic feed forward to increase the success probability of a linear optical implementation of a programmable phase gate from 25% to its theoretical limit of 50%. The feed forward applies a conditional…

Quantum Physics · Physics 2015-06-03 Martina Mikova , Helena Fikerova , Ivo Straka , Michal Micuda , Miroslav Jezek , Miloslav Dusek

We provide a characterization and analysis of the effects of dissipation on oscillator assisted (qubus) quantum gates. The effects can be understood and minimized by looking at the dynamics of the signal coherence and its entanglement with…

Quantum Physics · Physics 2010-08-23 Sebastien G. R. Louis , W. J. Munro , T. P. Spiller , Kae Nemoto

As a milestone for general-purpose computing machines, we demonstrate that quantum processors can be programmed to efficiently simulate dynamics that are not native to the hardware. Moreover, on noisy devices without error correction, we…

Unfolding is an important procedure in particle physics experiments which corrects for detector effects and provides differential cross section measurements that can be used for a number of downstream tasks, such as extracting fundamental…

High Energy Physics - Phenomenology · Physics 2023-07-19 Jay Chan , Benjamin Nachman

Non-Gaussian operations are essential for most bosonic quantum technologies. Yet, realizable non-Gaussian gates are rather limited in type and generally suffer from accuracy-duration trade-offs. In this work, we propose to use quantum…

Quantum Physics · Physics 2025-10-31 Pak-Tik Fong , Hoi-Kwan Lau

Three-dimensional random electron systems undergo quantum phase transitions and show rich phase diagrams. Examples of the phases are the band gap insulator, Anderson insulator, strong and weak topological insulators, Weyl semimetal, and…

Disordered Systems and Neural Networks · Physics 2017-03-16 Tomi Ohtsuki , Tomoki Ohtsuki

We investigate how relative phase information, encoded by a single qubit $H\,\varphi\,H$ gate sequence, is reflected in the quantum Fisher information (QFI) under noisy dynamics. Within a collision model framework, algorithmically prepared…

Quantum Physics · Physics 2025-09-23 S. Elham Mousavigharalari , Deniz Türkpençe

Adaptive measurements were recently shown to significantly improve the performance of quantum state tomography. Utilizing information about the system for the on-line choice of optimal measurements allows to reach the ultimate bounds of…

Variational quantum algorithms (VQAs) combining the advantages of parameterized quantum circuits and classical optimizers, promise practical quantum applications in the Noisy Intermediate-Scale Quantum era. The performance of VQAs heavily…

Developing quantum computers for real-world applications requires understanding theoretical sources of quantum advantage and applying those insights to design more powerful machines. Toward that end, we introduce a high-fidelity gate set…

Quantum Physics · Physics 2021-08-04 Alexander D. Hill , Mark J. Hodson , Nicolas Didier , Matthew J. Reagor

For years, the quantum/reversible circuit community has been convinced that: a) the addition of auxiliary qubits is instrumental in constructing a smaller quantum circuit; and, b) the introduction of quantum gates inside reversible circuits…

Quantum Physics · Physics 2011-08-01 Dmitri Maslov , Mehdi Saeedi

We develop several algorithms for performing quantum phase estimation based on basic measurements and classical post-processing. We present a pedagogical review of quantum phase estimation and simulate the algorithm to numerically determine…

Quantum Physics · Physics 2013-07-30 Krysta M. Svore , Matthew B. Hastings , Michael Freedman

Quantum computers have long been expected to efficiently solve complex classical differential equations. Most digital, fault-tolerant approaches use Carleman linearization to map nonlinear systems to linear ones and then apply quantum…

We demonstrate complete characterization of a two-qubit entangling process - a linear optics controlled-NOT gate operating with coincident detection - by quantum process tomography. We use maximum-likelihood estimation to convert the…

Quantum Physics · Physics 2008-11-26 J. L. O'Brien , G. J. Pryde , A. Gilchrist , D. F. V. James , N. K. Langford , T. C. Ralph , A. G. White

Quantum theory is based on a mathematical structure totally different from conventional arithmetic. Due to the symmetric nature of bosonic particles, annihilation or creation of single particles translates a quantum state depending on how…

Quantum Physics · Physics 2016-05-05 Mark Um , Junhua Zhang , Dingshun Lv , Yao Lu , Shuoming An , Jing-Ning Zhang , Hyunchul Nha , M. S. Kim , Kihwan Kim

Characterizing the noise in the set of gate operations that form the building blocks of a quantum computational device is a necessity for assessing the quality of the device. Here, we introduce randomized linear gate set tomography, an…

Quantum Physics · Physics 2021-08-25 Yanwu Gu , Rajesh Mishra , Berthold-Georg Englert , Hui Khoon Ng

We describe in detail a set of ideas for implementing qubits, quantum gates and quantum gate networks in a semiconductor heterostructure device. Our proposal is based on an extension of the technology used for surface acoustic wave (SAW)…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 C. H. W. Barnes , J. M. Shilton , A. M. Robinson

The numerical emulation of quantum physics and quantum chemistry often involves an intractable number of degrees of freedom and admits no known approximation in general form. In practice, representing quantum-mechanical states using…

We present an algorithm that prepares multidimensional Gaussian wavefunctions on qubit arrays and an application of such wavefunctions to multidimensional resampling, a technique useful in quantum digital simulation.

Quantum Physics · Physics 2009-10-06 Alexei Kitaev , William A. Webb