English
Related papers

Related papers: Universal quantum computer from a quantum magnet

200 papers

We study a model of quantum computation based on the continuously-parameterized yet finite-dimensional Hilbert space of a spin system. We explore the computational powers of this model by analyzing a pilot problem we refer to as the close…

Quantum Physics · Physics 2016-12-30 Mark Adcock , Peter Hoyer , Barry C. Sanders

We characterise a model of universal quantum computation where the register (computational) qubits are controlled by ancillary qubits, using only a single fixed interaction between register and ancillary qubits. No additional access is…

Quantum Physics · Physics 2013-10-25 Timothy J. Proctor , Erika Andersson , Viv Kendon

We propose a universal quantum computing scheme in which the orthogonal qubit states $|0>$ and $|1>$ are identical in their single-particle spin and charge properties. Each qubit is contained in a single quantum dot and gate operations are…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Jordan Kyriakidis , Guido Burkard

We present an approximative simulation method for quantum many-body systems based on coarse graining the space of the momentum transferred between interacting particles, which leads to effective Hamiltonians of reduced size with the…

Strongly Correlated Electrons · Physics 2009-11-09 Wei-Guo Yin , Wei Ku

We prove the STP=BQP conjecture of Freedman, Hastings and Shokrian-Zini [1], namely that the two-qubit singlet/triplet measurement is quantum computationally universal given only an initial ensemble of maximally mixed single qubits. This…

Quantum Physics · Physics 2023-11-13 Terry Rudolph , Shashank Soyuz Virmani

Entanglement between the constituents of a quantum system is an essential resource in the implementation of many quantum processes and algorithms. Indeed, universal quantum computation is possible by measuring individual qubits comprising…

Quantum Physics · Physics 2012-02-10 David L. Feder

Using electrostatic gates to control the electron positions, we present a new controlled-NOT gate based on quantum dots. The qubit states are chosen to be the spin states of an excess conductor electron in the quantum dot; and the main…

Quantum Physics · Physics 2007-05-23 Cyrus C. Y. Lin , Chopin Soo , Yin-Zhong Wu , Wei-Min Zhang

The general problem of finding the ground state energy of lattice Hamiltonians is known to be very hard, even for a quantum computer. We show here that this is the case even for translationally invariant systems. We also show that a quantum…

Quantum Physics · Physics 2009-11-13 K. G. H. Vollbrecht , J. I. Cirac

We show that the operators and the quadrupole and Zeeman Hamiltonians for a spin (3/2) can be represented in terms for a system of two coupling fictitious spins (1/2) using the Kronecker product of Pauli matrices. Particularly, the…

Quantum Physics · Physics 2017-07-11 G. B. Furman , V. M. Meerovich , V. L. Sokolovsky

It is shown that every one-dimensional Hamiltonian with short-range interaction admits a quantum Gibbs sampler [CKG23] with a system-size independent spectral gap at all finite temperatures. Consequently, their Gibbs states can be prepared…

Quantum Physics · Physics 2026-01-26 Thiago Bergamaschi , Chi-Fang Chen

We derive a quantum spin Hamiltonian of the spin-1/2 zigzag chain realized in a rare earth ytterbium-based magnetic insulator, YbCuS2. This material undergoes a transition at 0.95K to an incommensurate magnetic phase with small moments,…

Strongly Correlated Electrons · Physics 2024-08-02 Hidehiro Saito , Hiroki Nakai , Chisa Hotta

We prove the existence of gapped quantum Hamiltonians whose ground states exhibit an infinite entanglement length, as opposed to their finite correlation length. Using the concept of entanglement swapping, the localizable entanglement is…

Quantum Physics · Physics 2007-05-23 F. Verstraete , M. A. Martin-Delgado , J. I. Cirac

Recent work has characterised rigorously what it means for one quantum system to simulate another, and demonstrated the existence of universal Hamiltonians -- simple spin lattice Hamiltonians that can replicate the entire physics of any…

Quantum Physics · Physics 2021-10-26 Tamara Kohler , Stephen Piddock , Johannes Bausch , Toby Cubitt

Hamiltonian quantum gates controlled by classical electromagnetic fields form the basis of any realistic model of quantum computers. In this letter, we derive a lower bound on the field energy required to implement such gates and relate…

Quantum Physics · Physics 2025-10-15 Josey Stevens , Sebastian Deffner

To gain deeper insight into the dynamics of complex quantum systems we need a quantum leap in computer simulations. We can not translate quantum behaviour arising with superposition states or entanglement efficiently into the classical…

Quantum Physics · Physics 2008-02-28 Axel Friedenauer , Hector Schmitz , Jan Tibor Glückert , Diego Porras , Tobias Schätz

We initiate a research program for the systematic investigation of quantum superintegrable systems involving the interaction of two non-relativistic particles with spin $1/2$ moving in the three-dimensional Euclidean space. In this paper,…

Mathematical Physics · Physics 2025-06-13 O. Ogulcan Tuncer , I. Yurdusen

Quantum simulation using synthetic quantum systems offers unique opportunities to explore open questions in many-body physics and a path for the generation of useful entangled states. Nevertheless, so far many quantum simulators have been…

Quantum Physics · Physics 2024-07-04 Chengyi Luo , Haoqing Zhang , Anjun Chu , Chitose Maruko , Ana Maria Rey , James K. Thompson

Today's devices for quantum computing are still far from implementing useful and powerful quantum algorithms. Decoherence and the wish to resist the effects of errors in a system of quantum bits incurs a lot of overhead in the number of…

Quantum Physics · Physics 2007-05-23 Torsten Asselmeyer-Maluga , Matthias Kolbe , Helge Rose'

We construct a simple translationally invariant, nearest-neighbor Hamiltonian on a chain of 10-dimensional qudits that makes it possible to realize universal quantum computing without any external control during the computational process.…

Quantum Physics · Physics 2009-11-13 Daniel Nagaj , Pawel Wocjan

Universal set of quantum gates are realized from the conduction-band electron spin qubits of quantum dots embedded in a microcavity via two-channel Raman interaction. All of the gate operations are independent of the cavity mode states,…

Quantum Physics · Physics 2007-12-20 Ping Dong , Ming Yang , Zhuo-Liang Cao