Papers

C. Chamberland, Tomas Jochym-O'Connor, R. Laflamme·Sep 23, 2016

We analyze the resource overhead of recently proposed methods for universal fault-tolerant quantum computation using concatenated codes. Namely, we examine the concatenation of the 7-qubit Steane code with the 15-qubit Reed-Muller code, which allows ...

C. Gonçalves·Sep 22, 2016

The current work addresses quantum machine learning in the context of Quantum Artificial Neural Networks such that the networks' processing is divided in two stages: the learning stage, where the network converges to a specific quantum circuit, and t...

B. Heim, K. Svore, M. Hastings·Sep 20, 2016

Surface codes exploit topological protection to increase error resilience in quantum computing devices and can in principle be implemented in existing hardware. They are one of the most promising candidates for active error correction, not least due ...

Julius Wallnofer, W. Dur·Sep 19, 2016

We investigate measurement-based quantum communication with noisy resource states that are generated by entanglement purification. We consider the transmission of encoded information via noisy quantum channels using a measurement-based implementation...

Weidong Tang, Si-Xia Yu·Sep 5, 2016

Fast quantum data transmission faces several shortcomings such as the indistinguishability of some partly overlapping signals, the channel noises, and so on. Based on the encoded quantum data transmission protocol, an unconventional scheme is present...

James R. Wootton, Andreas Peter, J. R. Winkler +1 more·Aug 17, 2016

Current quantum technology is approaching the system sizes and fidelities required for quantum error correction. It is therefore important to determine exactly what is needed for proof-of-principle experiments, which will be a major step towards faul...

T. Morimae, K. Fujii, H. Nishimura·Aug 17, 2016

What happens if in QMA the quantum channel between Merlin and Arthur is noisy? It is not difficult to show that such a modification does not change the computational power as long as the noise is not too strong so that errors are correctable with hig...

J. Nichol, L. Orona, S. Harvey +4 more·Aug 15, 2016

Electron spins in semiconductors are promising qubits because their long coherence times enable nearly 109 coherent quantum gate operations. However, developing a scalable high-fidelity two-qubit gate remains challenging. Here, we demonstrate an enta...

A. Chenu, M. Beau, Jianshu Cao +1 more·Aug 3, 2016

We introduce a scheme for the quantum simulation of many-body decoherence based on the unitary evolution of a stochastic Hamiltonian. Modulating the strength of the interactions with stochastic processes, we show that the noise-averaged density matri...

O. Viyuela, O. Viyuela, O. Viyuela +5 more·Jul 29, 2016

Topological insulators and superconductors at finite temperature can be characterized by the topological Uhlmann phase. However, a direct experimental measurement of this invariant has remained elusive in condensed matter systems. Here, we report a m...

Chengxian Zhang, Xu-Chen Yang, Xin Wang·Jul 27, 2016

We study theoretically the responses of the dynamically corrected gates to time-dependent noises in the exchange-only spin qubit system. We consider $1/f$ noises having spectra proportional to $1/\omega^\alpha$, where the exponent $\alpha$ indicates ...

A. Darmawan, D. Poulin·Jul 21, 2016

The surface code is a many-body quantum system, and simulating it in generic conditions is computationally hard. While the surface code is believed to have a high threshold, the numerical simulations used to establish this threshold are based on simp...

M. F. Brandl, M. Mourik, L. Postler +15 more·Jul 18, 2016

We report on the design of a cryogenic setup for trapped ion quantum computing containing a segmented surface electrode trap. The heat shield of our cryostat is designed to attenuate alternating magnetic field noise, resulting in 120 dB reduction of ...

Yuki Takeuchi, K. Fujii, T. Morimae +1 more·Jul 6, 2016

Verifiable blind quantum computing allows a client with poor quantum devices to delegate universal quantum computing to a remote quantum server in such a way that the client's privacy is protected and the honesty of the server is verified. In existin...

M. Khezri, E. Mlinar, J. Dressel +1 more·Jun 14, 2016

Measuring a transmon qubit in circuit QED: dressed squeezed states Mostafa Khezri, 1, 2, ∗ Eric Mlinar, 1 Justin Dressel, 3, 4 and Alexander N. Korotkov 1 arXiv:1606.04204v2 [quant-ph] 1 Aug 2016 Department of Electrical and Computer Engineering, Uni...

Yannick Seis, Benjamin J. Brown, A. Sørensen +1 more·May 31, 2016

The high-fidelity storage of quantum information is crucial for quantum computation and communication. Many experimental platforms for these applications exhibit highly biased noise, with good resilience to spin depolarisation undermined by high deph...

Hoi-Kwan Lau, M. Plenio·May 30, 2016

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 co...

R. N. Alexander, P. Turner, S. Bartlett·May 25, 2016

Randomized benchmarking is routinely used as an efficient method for characterizing the performance of sets of elementary logic gates in small quantum devices. In the measurement-based model of quantum computation, logic gates are implemented via sin...

R. Blume-Kohout, J. Gamble, E. Nielsen +4 more·May 24, 2016

Quantum information processors promise fast algorithms for problems inaccessible to classical computers. But since qubits are noisy and error-prone, they will depend on fault-tolerant quantum error correction (FTQEC) to compute reliably. Quantum erro...

S. Rogers, D. Mulkey, Xiyuan Lu +2 more·May 20, 2016

Advances in quantum photonics have shown that chip-scale quantum devices are translating from the realm of basic research to applied technologies. Recent developments in integrated photonic circuits and single photon detectors indicate that the bottl...