English
Related papers

Related papers: Quantum One-Time Memories from Stateless Hardware,…

200 papers

Quantum Random Access Optimizer (QRAO) is a quantum-relaxation based optimization algorithm proposed by Fuller et al. that utilizes Quantum Random Access Code (QRAC) to encode multiple variables of binary optimization in a single qubit. The…

Quantum Physics · Physics 2023-04-04 Kosei Teramoto , Rudy Raymond , Eyuri Wakakuwa , Hiroshi Imai

Random-access quantum memories may offer computational advantages for quantum computers and networks. In this paper, we advance arrays of solid-state quantum memories towards their usage as random-access quantum memory. We perform quantum…

Quantum Physics · Physics 2025-09-16 Markus Teller , Susana Plascencia , Samuele Grandi , Hugues de Riedmatten

Quantum cryptography is a rapidly-developing area which leverages quantum information to accomplish classically-impossible tasks. In many of these protocols, quantum states are used as long-term cryptographic keys. Typically, this is to…

Quantum Physics · Physics 2025-11-07 Omri Shmueli , Mark Zhandry

Quantum machine learning models have the potential to offer speedups and better predictive accuracy compared to their classical counterparts. However, these quantum algorithms, like their classical counterparts, have been shown to also be…

Quantum Physics · Physics 2021-05-27 Maurice Weber , Nana Liu , Bo Li , Ce Zhang , Zhikuan Zhao

We design machines that learn how to rotate a quantum bit about an initially unknown direction, encoded in the state of a spin-j particle. We show that a machine equipped with a quantum memory of O(log j) qubits can outperform all machines…

Quantum Physics · Physics 2021-09-28 Yin Mo , Giulio Chiribella

Initializing classical data in a quantum device is an essential step in many quantum algorithms. As a consequence of measurement and noisy operations, some algorithms need to reinitialize the prepared state several times during its…

Quantum Physics · Physics 2022-06-27 Tiago M. L. de Veras , Leon D. da Silva , Adenilton J. da Silva

Quantum optimization methods use a continuous degree-of-freedom of quantum states to heuristically solve combinatorial problems, such as the MAX-CUT problem, which can be attributed to various NP-hard combinatorial problems. This paper…

Quantum Physics · Physics 2025-01-15 Ruho Kondo , Yuki Sato , Rudy Raymond , Naoki Yamamoto

Quantum memory, serving as a crucial device for storing and releasing quantum states, holds significant importance in long-distance quantum communications. Up to date, quantum memories have been realized in many different systems. However,…

Quantum Physics · Physics 2025-02-20 Ming-Shuo Sun , Chun-Hui Zhang , Yi-Zhen Luo , Shuang Wang , Yun Liu , Jian Li , Qin Wang

We describe a quantum algorithm to prepare an arbitrary pure state of a register of a quantum computer with fidelity arbitrarily close to 1. Our algorithm is based on Grover's quantum search algorithm. For sequences of states with suitably…

Quantum Physics · Physics 2007-05-23 Andrei N. Soklakov , Ruediger Schack

Giovannetti, Lloyd, and Maccone [Phys. Rev. Lett. 100, 160501] proposed a quantum random access memory (QRAM) architecture to retrieve arbitrary superpositions of $N$ (quantum) memory cells via $O(\log(N))$ quantum switches and $O(\log(N))$…

Quantum computers provide an opportunity to efficiently sample from probability distributions that include non-trivial interference effects between amplitudes. Using a simple process wherein all possible state histories can be specified by…

Quantum Physics · Physics 2019-08-22 Davide Provasoli , Benjamin Nachman , Wibe A. de Jong , Christian W Bauer

The rapid advancement of quantum hardware calls for the development of reliable methods to certify its correct functioning. However, existing certification tests often fall short: they either rely on flawless state preparation and…

Quantum Physics · Physics 2026-03-16 Jan Nöller , Nikolai Miklin , Martin Kliesch , Mariami Gachechiladze

Universal QRAM (U-QRAM) is a fixed, data-independent unitary interface that implements coherent random-access reads relative to a designated computational "truth-table" basis on the memory register. This work studies restricted-access…

Quantum Physics · Physics 2025-12-23 Leonardo Bohac

We propose a new method to autonomously correct for errors of a logical qubit induced by energy relaxation. This scheme encodes the logical qubit as a multi-component superposition of coherent states in a harmonic oscillator, more…

We introduce a new method to reconstruct unknown quantum states out of incomplete and noisy information. The method is a linear convex optimization problem, therefore with a unique minimum, which can be efficiently solved with Semidefinite…

Quantum Physics · Physics 2011-12-01 Thiago O. Maciel , André T. Cesário , Reinaldo O. Vianna

For realizing a quantum memory we suggest to first encode quantum information via a quantum error correcting code and then concatenate combined decoding and re-encoding operations. This requires that the encoding and the decoding operation…

Quantum Physics · Physics 2007-05-23 Dirk Schlingemann

We analyze surface codes, the topological quantum error-correcting codes introduced by Kitaev. In these codes, qubits are arranged in a two-dimensional array on a surface of nontrivial topology, and encoded quantum operations are associated…

Quantum Physics · Physics 2009-11-07 Eric Dennis , Alexei Kitaev , Andrew Landahl , John Preskill

We provide modular circuit-level implementations and resource estimates for several methods of block-encoding a dense $N\times N$ matrix of classical data to precision $\epsilon$; the minimal-depth method achieves a $T$-depth of…

Quantum hashing is a promising generalization of the cryptographic hashing concept on the quantum domain. In this paper, we construct a quantum hash via a sequence of single-photon states and perform a proof-of-principle experiment using…

Quantum Physics · Physics 2021-11-24 D. A. Turaykhanov , D. O. Akat'ev , A. V. Vasiliev , F. M. Ablayev , A. A. Kalachev

Quantum random access memory (QRAM) is a central primitive for coherent data access in quantum algorithms, yet it remains controversial in practice because the wall-clock cost of "one lookup" can hide routing depth, control overhead, and…

Quantum Physics · Physics 2026-01-09 Leonardo Bohac