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Related papers: Quantum State Preparation and Non-Unitary Evolutio…

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Implementing a qubit quantum computer in continuous-variable systems conventionally requires the engineering of specific interactions according to the encoding basis states. In this work, we present a unified formalism to conduct universal…

Quantum Physics · Physics 2016-09-06 Hoi-Kwan Lau , Martin B. Plenio

We present a quantum algorithm for adiabatic state preparation on a gate-based quantum computer, with complexity polylogarithmic in the inverse error. Our algorithm digitally simulates the adiabatic evolution between two self-adjoint…

Quantum Physics · Physics 2022-03-04 Kianna Wan , Isaac H. Kim

In numerical approaches to solving differential equations on a lattice, a representation of the derivative operator that correctly matches the continuum behaviour of functions of momentum up to the band limit must be non-local. We present…

Unknown unitary inversion is a fundamental primitive in quantum computing and physics. Although recent work has demonstrated that quantum algorithms can invert arbitrary unknown unitaries without accessing their classical descriptions,…

Quantum Physics · Physics 2025-06-26 Yin Mo , Tengxiang Lin , Xin Wang

Quantum computing is powerful because unitary operators describing the time-evolution of a quantum system have exponential size in terms of the number of qubits present in the system. We develop a new "Singular value transformation"…

Quantum Physics · Physics 2020-02-21 András Gilyén , Yuan Su , Guang Hao Low , Nathan Wiebe

Variational hybrid quantum-classical algorithms are promising candidates for near-term implementation on quantum computers. In these algorithms, a quantum computer evaluates the cost of a gate sequence (with speedup over classical cost…

Quantum Physics · Physics 2019-06-27 Ryan LaRose , Arkin Tikku , Étude O'Neel-Judy , Lukasz Cincio , Patrick J. Coles

Finding the ground state of a Hamiltonian system is of great significance in many-body quantum physics and quantum chemistry. We propose an improved iterative quantum algorithm to prepare the ground state of a Hamiltonian. The crucial point…

Quantum Physics · Physics 2022-10-25 Jin-Min Liang , Qiao-Qiao Lv , Shu-Qian Shen , Ming Li , Zhi-Xi Wang , Shao-Ming Fei

We propose a scheme for scalable and universal quantum computation using diatomic bits with conditional dipole-dipole interaction, trapped within an optical lattice. The qubit states are encoded by the scattering state and the bound…

Quantum Physics · Physics 2007-05-23 Chaohong Lee , Elena A. Ostrovskaya

We show how a quantum computer may efficiently simulate a disordered Hamiltonian, by incorporating a pseudo-random number generator directly into the time evolution circuit. This technique is applied to quantum simulation of few-body…

Disordered Systems and Neural Networks · Physics 2020-03-25 Andrei Alexandru , Paulo F. Bedaque , Scott Lawrence

Simulating physical systems on quantum devices is one of the most promising applications of quantum technology. Current quantum approaches to simulating open quantum systems are still practically challenging on NISQ-era devices, because…

Quantum Physics · Physics 2024-09-09 Joseph Peetz , Scott E. Smart , Spyros Tserkis , Prineha Narang

We explore the possibility of adding complex absorbing potential at the boundaries when solving the one-dimensional real-time Schr\"odinger evolution on a grid using a quantum computer with a fully quantum algorithm described on a $n$ qubit…

Quantum Physics · Physics 2024-04-10 Mariane Mangin-Brinet , Jing Zhang , Denis Lacroix , Edgar Andres Ruiz Guzman

Quantum algorithms for Hamiltonian simulation and linear differential equations more generally have provided promising exponential speed-ups over classical computers on a set of problems with high real-world interest. However, extending…

Quantum Physics · Physics 2025-05-14 Noah Brüstle , Nathan Wiebe

We show that the discrete-time evolution of an open quantum system generated by a single quantum channel $T$ can be embedded in the discrete-time evolution of an enlarged closed quantum system, i.e. we construct a unitary dilation of the…

Mathematical Physics · Physics 2020-08-17 Frederik vom Ende , Gunther Dirr

Quantum annealing processors typically control qubits in unison, attenuating quantum fluctuations uniformly until the applied system Hamiltonian is diagonal in the computational basis. This simplifies control requirements, allowing…

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…

Singular value decomposition is central to many problems in engineering and scientific fields. Several quantum algorithms have been proposed to determine the singular values and their associated singular vectors of a given matrix. Although…

Quantum Physics · Physics 2021-06-30 Xin Wang , Zhixin Song , Youle Wang

Unitary decomposition is a widely used method to map quantum algorithms to an arbitrary set of quantum gates. Efficient implementation of this decomposition allows for translation of bigger unitary gates into elementary quantum operations,…

Quantum Physics · Physics 2024-03-14 A. M. Krol , A. Sarkar , I. Ashraf , Z. Al-Ars , K. Bertels

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

Optimal control techniques are applied for the decomposition of unitary quantum operations into a sequence of single-qubit gates and entangling operations. To this end, we modify a gradient-ascent algorithm developed for systems of coupled…

Quantum Physics · Physics 2009-01-15 V. Nebendahl , H. Haffner , C. F. Roos

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