Quantum – the open journal for quantum science

Quantum has published 968 Papers in 7 Volumes, as well as 72 Views in Quantum Views.

Paper

Practical randomness amplification and privatisation with implementations on quantum computers

Cameron Foreman, Sherilyn Wright, Alec Edgington, Mario Berta, and Florian J. Curchod,

Quantum 7, 969 (2023).

We present an end-to-end and practical randomness amplification and privatisation protocol based on Bell tests. This allows the building of device-independent random number generators which…

Paper

When does a particle arrive?

Simone Roncallo, Krzysztof Sacha, and Lorenzo Maccone,

Quantum 7, 968 (2023).

We compare the proposals that have appeared in the literature to describe a measurement of the time of arrival of a quantum particle at a detector. We show that there are multiple regimes wh…

Paper

Dihedral twist liquid models from emergent Majorana fermions

Jeffrey C. Y. Teo and Yichen Hu,

Quantum 7, 967 (2023).

We present a family of electron-based coupled-wire models of bosonic orbifold topological phases, referred to as twist liquids, in two spatial dimensions. All local fermion degrees of freedo…

Paper

Characterization of variational quantum algorithms using free fermions

Gabriel Matos, Chris N. Self, Zlatko Papić, Konstantinos Meichanetzidis, and Henrik Dreyer,

Quantum 7, 966 (2023).

We study variational quantum algorithms from the perspective of free fermions. By deriving the explicit structure of the associated Lie algebras, we show that the Quantum Approximate Optimiz…

Paper

Quantum-enhanced differential atom interferometers and clocks with spin-squeezing swapping

Robin Corgier, Marco Malitesta, Augusto Smerzi, and Luca Pezzè,

Quantum 7, 965 (2023).

Thanks to common-mode noise rejection, differential configurations are crucial for realistic applications of phase and frequency estimation with atom interferometers. Currently, differential…

Paper

Simulating quantum circuits using tree tensor networks

Philipp Seitz, Ismael Medina, Esther Cruz, Qunsheng Huang, and Christian B. Mendl,

Quantum 7, 964 (2023).

We develop and analyze a method for simulating quantum circuits on classical computers by representing quantum states as rooted tree tensor networks. Our algorithm first determines a suitabl…

Paper

Beyond transcoherent states: Field states for effecting optimal coherent rotations on single or multiple qubits

Aaron Z. Goldberg, Aephraim M. Steinberg, and Khabat Heshami,

Quantum 7, 963 (2023).

Semiclassically, laser pulses can be used to implement arbitrary transformations on atomic systems; quantum mechanically, residual atom-field entanglement spoils this promise. Transcoherent…

Paper

Optimal Hamiltonian simulation for time-periodic systems

Kaoru Mizuta and Keisuke Fujii,

Quantum 7, 962 (2023).

The implementation of time-evolution operators $U(t)$, called Hamiltonian simulation, is one of the most promising usage of quantum computers. For time-independent Hamiltonians, qubitization h…

Paper

Cooperative quantum information erasure

Lorenzo Buffoni and Michele Campisi,

Quantum 7, 961 (2023).

We demonstrate an information erasure protocol that resets $N$ qubits at once. The method displays exceptional performances in terms of energy cost (it operates nearly at Landauer energy cost…

Paper

General properties of fidelity in non-Hermitian quantum systems with PT symmetry

Yi-Ting Tu, Iksu Jang, Po-Yao Chang, and Yu-Chin Tzeng,

Quantum 7, 960 (2023).

The fidelity susceptibility is a tool for studying quantum phase transitions in the Hermitian condensed matter systems. Recently, it has been generalized with the biorthogonal basis for the…

Paper

Hybrid divide-and-conquer approach for tree search algorithms

Mathys Rennela, Sebastiaan Brand, Alfons Laarman, and Vedran Dunjko,

Quantum 7, 959 (2023).

One of the challenges of quantum computers in the near- and mid- term is the limited number of qubits we can use for computations. Finding methods that achieve useful quantum improvements un…

Paper

Quantum States of Fields for Quantum Split Sources

Lin-Qing Chen, Flaminia Giacomini, and Carlo Rovelli,

Quantum 7, 958 (2023).

Field mediated entanglement experiments probe the quantum superposition of macroscopically distinct field configurations. We show that this phenomenon can be described by using a transparent…

Paper

Universal construction of decoders from encoding black boxes

Satoshi Yoshida, Akihito Soeda, and Mio Murao,

Quantum 7, 957 (2023).

Isometry operations encode the quantum information of the input system to a larger output system, while the corresponding decoding operation would be an inverse operation of the encoding iso…

Paper

Optimal (controlled) quantum state preparation and improved unitary synthesis by quantum circuits with any number of ancillary qubits

Pei Yuan and Shengyu Zhang,

Quantum 7, 956 (2023).

As a cornerstone for many quantum linear algebraic and quantum machine learning algorithms, controlled quantum state preparation (CQSP) aims to provide the transformation of…

Paper

Time-marching based quantum solvers for time-dependent linear differential equations

Di Fang, Lin Lin, and Yu Tong,

Quantum 7, 955 (2023).

The time-marching strategy, which propagates the solution from one time step to the next, is a natural strategy for solving time-dependent differential equations on classical computers, as w…

Paper

Efficient separation of quantum from classical correlations for mixed states with a fixed charge

Christian Carisch and Oded Zilberberg,

Quantum 7, 954 (2023).

Entanglement is the key resource for quantum technologies and is at the root of exciting many-body phenomena. However, quantifying the entanglement between two parts of a real-world quantum…