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Related papers: Counterfactual universal quantum computation

200 papers

Decoherence-free subspaces allow for the preparation of coherent and entangled qubits for quantum computing. Decoherence can be dramatically reduced, yet dissipation is an integral part of the scheme in generating stable qubits and…

Quantum Physics · Physics 2009-11-07 Ben Tregenna , Almut Beige , Peter L. Knight

Counterfactual communication, i.e., communication without particle travelling in the transmission channel, is a bizarre quantum effect. Starting from interaction-free measurements many protocols achieving various tasks from counterfactual…

Quantum Physics · Physics 2019-06-05 Lev Vaidman

Entanglement is essential for quantum computation. However, disentanglement is also necessary. It can be achieved without the need of classical operations (measurements). Two examples are analyzed: the discrete Fourier transform and error…

Quantum Physics · Physics 2009-10-30 Asher Peres

We examine the effect of previous history on starting a computation on a quantum computer. Specifically, we assume that the quantum register has some unknown state on it, and it is required that this state be cleared and replaced by a…

Quantum Physics · Physics 2007-05-23 Subhash Kak

An implementation of a quantum computer based on space states in double quantum dots is discussed. There is no charge transfer in qubits during calculation, therefore, uncontrollable entan-glement between them due to long-range Coulomb…

Quantum Physics · Physics 2010-07-22 S. Filippov , V. Vyurkov , L. Gorelik

In this research notebook in the four-part, quantum computation and applications, quantum computation and algorithms, quantum communication protocol, and universal quantum computation for quantum engineers, researchers, and scientists, we…

Quantum Physics · Physics 2021-01-07 Bhupesh Bishnoi

The universal transpose of quantum states is an anti-unitary transformation that is not allowed in quantum theory. In this work, we investigate approximating the universal transpose of quantum states of two-level systems (qubits) using the…

Quantum Physics · Physics 2015-05-19 Hyang-Tag Lim , Young-Sik Ra , Yong-Su Kim , Joonwoo Bae , Yoon-Ho Kim

We first use the quantum method to replicate the well-known results of a single atom relaxing, whilst demonstrating the intuitive picture it provides for dissipative dynamics. By use of individual "quantum trajectories", the method allows…

Quantum Physics · Physics 2022-02-10 Charles A. McDermott

By analyzing the key properties of black holes from the point of view of quantum information, we derive a model-independent picture of black hole quantum computing. It has been noticed that this picture exhibits striking similarities with…

High Energy Physics - Theory · Physics 2017-04-11 Gia Dvali , Cesar Gomez , Dieter Lust , Yasser Omar , Benedikt Richter

Quantized integrable systems can be made to perform universal quantum computation by the application of a global time-varying control. The action-angle variables of the integrable system function as qubits or qudits, which can be coupled…

Quantum Physics · Physics 2014-08-05 Seth Lloyd , Simone Montangero

We introduce the concept of quantum supermap, describing the most general transformation that maps an input quantum operation into an output quantum operation. Since quantum operations include as special cases quantum states, effects, and…

Quantum Physics · Physics 2008-10-22 G. Chiribella , G. M. D'Ariano , P. Perinotti

Using a quantumlike description for light propagation in nonhomogeneous optical fibers, quantum information processing can be implemented by optical means. Quantum-like bits (qulbits) are associated to light modes in the optical fiber and…

Quantum Physics · Physics 2009-11-07 M. A. Man'ko , V. I. Man'ko , R. Vilela Mendes

Encryption of data is fundamental to secure communication in the modern world. Beyond encryption of data lies obfuscation, i.e., encryption of functionality. It is well-known that the most powerful means of obfuscating classical programs,…

Quantum Physics · Physics 2016-02-05 Gorjan Alagic , Bill Fefferman

We combine the eyebrow-raising quantum phenomena of erasure and counterfactuality for the first time, proposing a simple yet unusual quantum eraser: A distant Bob can decide to erase which-path information from Alice's photon, dramatically…

Quantum Physics · Physics 2018-02-12 Hatim Salih

Any unitary transformation of quantum computational networks is explicitly decomposed, in an exact and unified form, into a sequence of a limited number of one-qubit quantum gates and the two-qubit diagonal gates that have diagonal unitary…

Quantum Physics · Physics 2007-05-23 Xijia Miao

Quantum computation offers the potential to solve fundamental yet otherwise intractable problems across a range of active fields of research. Recently, universal quantum-logic gate sets - the building blocks for a quantum computer - have…

A quantum algorithm succeeds not because the superposition principle allows 'the computation of all values of a function at once' via 'quantum parallelism,' but rather because the structure of a quantum state space allows new sorts of…

Quantum Physics · Physics 2010-05-17 Jeffrey Bub

We develop a theory and accompanying mathematical model for quantum communication via any number of intermediate entanglement swapping operations and solve numerically for up to three intermediate entanglement swapping operations. Our model…

Quantum Physics · Physics 2014-09-08 Aeysha Khalique , Barry C. Sanders

A quantum walk is a time-homogeneous quantum-mechanical process on a graph defined by analogy to classical random walk. The quantum walker is a particle that moves from a given vertex to adjacent vertices in quantum superposition. Here we…

Quantum Physics · Physics 2013-02-18 Andrew M. Childs , David Gosset , Zak Webb

Error correction will add so much overhead to large quantum computations that we suspect the most efficient algorithms will use a classical co-processor to do as much work as possible. We present a method to offload portions of a quantum…

Quantum Physics · Physics 2020-08-12 Samuel Jaques , Craig Gidney