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Related papers: Cartan Decomposition of SU(2^n), Constructive Cont…

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We consider quantum transition amplitudes, partition functions and observables for 3D spin foam models within $SU(2)$ quantum group deformation symmetry, where the deformation parameter is a complex fifth root of unity. By considering…

High Energy Physics - Theory · Physics 2022-01-13 Marcelo Amaral , Raymond Aschheim , Klee Irwin

We present a simple algorithm that implements an arbitrary $n$-qubit unitary operator using a Clifford+T circuit with T-count $O(2^{4n/3} n^{2/3})$. This improves upon the previous best known upper bound of $O(2^{3n/2} n)$, while the best…

Quantum Physics · Physics 2025-10-01 Xinyu Tan

In this Letter, we present two analytic expressions that most generally simulate $n$-qubit controlled-$U$ gates with standard one-qubit gates and CNOT gates using exponential and polynomial complexity respectively. Explicit circuits and…

Quantum Physics · Physics 2007-08-27 Yang Liu , Gui Lu Long , Yang Sun

This paper examines the controllability for quantum control systems with SU(1,1) dynamical symmetry, namely, the ability to use some electromagnetic field to redirect the quantum system toward a desired evolution. The problem is formalized…

Optimization and Control · Mathematics 2007-08-24 Jian-Wu Wu , Chun-Wen Li , Jing Zhang , Tzyh-Jong Tarn

The work presented here extends upon the best known universal quantum circuit, the Quantum Shannon Decomposition proposed in [Vivek V. Shende, Stephen S. Bullock and Igor Markov, Synthesis of Quantum Logic Circuits, IEEE Trans.…

Quantum Physics · Physics 2009-11-13 Byron Drury , Peter J. Love

We present a unitary control pulse design method for a scalable quantum computer architecture based on electron spins in lateral quantum dots. We employ simultaneous control of spin interactions and derive the functional forms of spin…

Quantum Physics · Physics 2024-02-14 Bohdan Khromets , Zach D. Merino , Jonathan Baugh

We investigate N-extended supersymmetry in one-dimensional quantum mechanics on a circle with point singularities. For any integer n, N=2n supercharges are explicitly constructed and a class of point singularities compatible with…

High Energy Physics - Theory · Physics 2009-11-10 Tomoaki Nagasawa , Makoto Sakamoto , Kazunori Takenaga

In quantum computation every unitary operation can be decomposed into quantum circuits-a series of single-qubit rotations and a single type entangling two-qubit gates, such as controlled-NOT (CNOT) gates. Two measures are important when…

Quantum Physics · Physics 2011-03-07 Martin Plesch , Časlav Brukner

The quantum Fourier transform (QFT) is a powerful tool in quantum computing. The main ingredients of QFT are formed by the Walsh-Hadamard transform H and phase shifts P(.), both of which are 2x2 unitary matrices as operators on the…

Quantum Physics · Physics 2007-05-23 Charles M. Bowden , Goong Chen , Zijian Diao , Andreas Klappenecker

The model of a topological quantum computer is a promising one due to its natural resistance to noise and other errors. Operations in such a computer are implemented by braiding the trajectories of anyons. While it is easy to understand how…

High Energy Physics - Theory · Physics 2026-05-06 Sergey Mironov , Andrey Morozov

We show, within the circuit model, how any quantum computation can be efficiently performed using states with only real amplitudes (a result known within the Quantum Turing Machine model). This allows us to identify a 2-qubit (in fact…

Quantum Physics · Physics 2007-05-23 Terry Rudolph , Lov Grover

As quantum processing units grow in size and precision we enter the stage where quantum algorithms can be tested on actual quantum devices. To implement a given quantum circuit on a given quantum device, one has to express the circuit in…

Quantum Physics · Physics 2025-06-23 Yaqing X. Wang , Tommaso Calarco , Felix Motzoi , Matthias M. Müller

An important result in the theory of quantum control is the "universality" of $2$-local unitary gates, i.e. the fact that any global unitary evolution of a system of $L$ qudits can be implemented by composition of $2$-local unitary gates.…

Quantum Physics · Physics 2026-02-10 Marco Lastres , Frank Pollmann , Sanjay Moudgalya

Decompositions of the unitary group U(n) are useful tools in quantum information theory as they allow one to decompose unitary evolutions into local evolutions and evolutions causing entanglement. Several recursive decompositions have been…

Quantum Physics · Physics 2009-11-13 Mehmet Dagli , Domenico D'Alessandro , Jonathan D. H. Smith

Just as any state of a single qubit or 2-level system can be obtained from any other state by a rotation operator parametrized by three real Euler angles, we show how any state of an n-qubit or 2^n-level system can be obtained from any…

Quantum Physics · Physics 2007-05-23 W. E. Baylis , R. Cabrera , C. Rangan

Simulating quantum dynamics on classical computers is challenging for large systems due to the significant memory requirements. Simulation on quantum computers is a promising alternative, but fully optimizing quantum circuits to minimize…

Most quantum compiling efforts rely on standard two-qubit basis gates, such as CX and iSWAP, to implement general quantum operations. However, with the advancement of quantum architecture design, more nonstandard two-qubit gates can now be…

Quantum Physics · Physics 2025-03-05 Anbang Wu , Jingwen Leng , Minyi Guo

A quantum unitary gate is realized in this paper by perturbing a free charged particle in a one-dimensional box with a time- and position-varying electric field. The perturbed Hamiltonian is composed of a free particle Hamiltonian plus a…

Quantum Physics · Physics 2023-04-14 Kumar Gautam

A key task in quantum computation is the application of a sequence of gates implementing a specific unitary operation. However, the decomposition of an arbitrary unitary operation into simpler quantum gates is a nontrivial problem. Here we…

Quantum Physics · Physics 2016-03-23 Swathi S. Hegde , K. R. Koteswara Rao , T. S. Mahesh

In this work, we study distributions of unitaries generated by random quantum circuits containing only symmetry-respecting gates. We develop a unified approach applicable to all symmetry groups and obtain an equation that determines the…

Quantum Physics · Physics 2024-10-16 Hanqing Liu , Austin Hulse , Iman Marvian