Quantum

Paper

Randomized Benchmarking as Convolution: Fourier Analysis of Gate Dependent Errors

Seth T. Merkel, Emily J. Pritchett, and Bryan H. Fong,

Quantum 5, 581 (2021).

We show that the Randomized Benchmarking (RB) protocol is a convolution amenable to Fourier space analysis. By adopting the mathematical framework of Fourier transforms of matrix-valued func…

Paper

Clifford Circuit Optimization with Templates and Symbolic Pauli Gates

Sergey Bravyi, Ruslan Shaydulin, Shaohan Hu, and Dmitri Maslov,

Quantum 5, 580 (2021).

The Clifford group is a finite subgroup of the unitary group generated by the Hadamard, the CNOT, and the Phase gates. This group plays a prominent role in quantum error correction, randomiz…

Paper

Emergent Replica Conformal Symmetry in Non-Hermitian SYK$_2$ Chains

Pengfei Zhang, Shao-Kai Jian, Chunxiao Liu, and Xiao Chen,

Quantum 5, 579 (2021).

Recently, the steady states of non-unitary free fermion dynamics are found to exhibit novel critical phases with power-law squared correlations and a logarithmic subsystem entanglement. In t…

Paper

Efficient verification of Boson Sampling

Ulysse Chabaud, Frédéric Grosshans, Elham Kashefi, and Damian Markham,

Quantum 5, 578 (2021).

The demonstration of quantum speedup, also known as quantum computational supremacy, that is the ability of quantum computers to outperform dramatically their classical counterparts, is an i…

Paper

Fast-forwarding quantum evolution

Shouzhen Gu, Rolando D. Somma, and Burak Şahinoğlu,

Quantum 5, 577 (2021).

We investigate the problem of fast-forwarding quantum evolution, whereby the dynamics of certain quantum systems can be simulated with gate complexity that is sublinear in the evolution time…

Paper

Multiport based teleportation – transmission of a large amount of quantum information

Piotr Kopszak, Marek Mozrzymas, Michał Studziński, and Michał Horodecki,

Quantum 5, 576 (2021).

We analyse the problem of transmitting a number of unknown quantum states or one composite system in one go. We derive a lower bound on the performance of such process, measured in the entan…

Paper

On safe post-selection for Bell tests with ideal detectors: Causal diagram approach

Pawel Blasiak, Ewa Borsuk, and Marcin Markiewicz,

Quantum 5, 575 (2021).

Reasoning about Bell nonlocality from the correlations observed in post-selected data is always a matter of concern. This is because conditioning on the outcomes is a source of non-causal co…

Paper

High-precision quantum algorithms for partial differential equations

Andrew M. Childs, Jin-Peng Liu, and Aaron Ostrander,

Quantum 5, 574 (2021).

Quantum computers can produce a quantum encoding of the solution of a system of differential equations exponentially faster than a classical algorithm can produce an explicit description. Ho…

Paper

On solving classes of positive-definite quantum linear systems with quadratically improved runtime in the condition number

Davide Orsucci and Vedran Dunjko,

Quantum 5, 573 (2021).

Quantum algorithms for solving the Quantum Linear System (QLS) problem are among the most investigated quantum algorithms of recent times, with potential applications including the solution…

Paper

Encoding strongly-correlated many-boson wavefunctions on a photonic quantum computer: application to the attractive Bose-Hubbard model

Saad Yalouz, Bruno Senjean, Filippo Miatto, and Vedran Dunjko,

Quantum 5, 572 (2021).

Variational quantum algorithms (VQA) are considered as some of the most promising methods to determine the properties of complex strongly correlated quantum many-body systems, especially fro…

Paper

Roads to objectivity: Quantum Darwinism, Spectrum Broadcast Structures, and Strong quantum Darwinism – a review

J. K. Korbicz,

Quantum 5, 571 (2021).

The problem of objectivity, i.e. how to explain on quantum grounds the objective character of the macroscopic world, is one of the aspects of the celebrated quantum-to-classical transition.…

Paper

Quantum repeaters based on individual electron spins and nuclear-spin-ensemble memories in quantum dots

Kenneth Sharman, Faezeh Kimiaee Asadi, Stephen C Wein, and Christoph Simon,

Quantum 5, 570 (2021).

Inspired by recent developments in the control and manipulation of quantum dot nuclear spins, which allow for the transfer of an electron spin state to the surrounding nuclear-spin ensemble…

Paper

Quantum Advantage for Shared Randomness Generation

Tamal Guha, Mir Alimuddin, Sumit Rout, Amit Mukherjee, Some Sankar Bhattacharya, and Manik Banik,

Quantum 5, 569 (2021).

Paper

The Fermionic Quantum Emulator

Nicholas C. Rubin, Klaas Gunst, Alec White, Leon Freitag, Kyle Throssell, Garnet Kin-Lic Chan, Ryan Babbush, and Toru Shiozaki,

Quantum 5, 568 (2021).

The fermionic quantum emulator (FQE) is a collection of protocols for emulating quantum dynamics of fermions efficiently taking advantage of common symmetries present in chemical, materials,…

Paper

Simultaneous Perturbation Stochastic Approximation of the Quantum Fisher Information

Julien Gacon, Christa Zoufal, Giuseppe Carleo, and Stefan Woerner,

Quantum 5, 567 (2021).

The Quantum Fisher Information matrix (QFIM) is a central metric in promising algorithms, such as Quantum Natural Gradient Descent and Variational Quantum Imaginary Time Evolution. Computing…

Paper

Faster Coherent Quantum Algorithms for Phase, Energy, and Amplitude Estimation

Patrick Rall,

Quantum 5, 566 (2021).

We consider performing phase estimation under the following conditions: we are given only one copy of the input state, the input state does not have to be an eigenstate of the unitary, and t…

Category: Paper