542 citations · 2k across the 56 of their papers we have counts for
48 papers · 1 filter
Universal algorithms for quantum data learning
Marco Fanizza, Michalis Skotiniotis, John Calsamiglia +2
Operating quantum sensors and quantum computers would make data in the form of quantum states available for purely quantum processing, opening new avenues for studying physical pro…
Online identification of symmetric pure states
Gael Sentís, Esteban Martínez-Vargas, Ramon Muñoz-Tapia
We consider online strategies for discriminating between symmetric pure states with zero error when copies of the states are provided. Optimized online strategies involve local…
Quantum Sequential Hypothesis Testing
Esteban Martínez-Vargas, Christoph Hirche, Gael Sentís +4
We introduce sequential analysis in quantum information processing, by focusing on the fundamental task of quantum hypothesis testing. In particular our goal is to discriminate bet…
Reinforcement learning for optimal error correction of toric codes
Laia Domingo Colomer, Michalis Skotiniotis, Ramon Muñoz-Tapia
We apply deep reinforcement learning techniques to design high threshold decoders for the toric code under uncorrelated noise. By rewarding the agent only if the decoding procedure…
Certified answers for ordered quantum discrimination problems
Esteban Martínez-Vargas, Ramon Munoz-Tapia
We investigate the quantum state discrimination task for sets of linear independent pure states with an intrinsic ordering. This structured discrimination problems allow for a nove…
Unsupervised classification of quantum data
Gael Sentís, Alex Monràs, Ramon Muñoz-Tapia +2
We introduce the problem of unsupervised classification of quantum data, namely, of systems whose quantum states are unknown. We derive the optimal single-shot protocol for the bin…
Experimentally detecting a quantum change point via Bayesian inference
Shang Yu, Chang-Jiang Huang, Jian-Shun Tang +15
Detecting a change point is a crucial task in statistics that has been recently extended to the quantum realm. A source state generator that emits a series of single photons in a d…
Exact Identification of a Quantum Change Point
Gael Sentís, John Calsamiglia, Ramon Munoz-Tapia
The detection of change points is a pivotal task in statistical analysis. In the quantum realm, it is a new primitive where one aims at identifying the point where a source that su…
Probabilistic metrology or how some measurement outcomes render ultra-precise estimates
J. Calsamiglia, B. Gendra, R. Munoz-Tapia +1
We show on theoretical grounds that, even in the presence of noise, probabilistic measurement strategies (which have a certain probability of failure or abstention) can provide, up…
Quantum change point
Gael Sentís, Emilio Bagan, John Calsamiglia +2
Sudden changes are ubiquitous in nature. Identifying them is of crucial importance for a number of applications in medicine, biology, geophysics, and social sciences. Here we inves…
Probabilistic metrology defeats ultimate deterministic bound
J. Calsamiglia, B. Gendra, R. Munoz-Tapia +1
Quantum-enhanced measurements exploit quantum mechanical effects to provide ultra-precise estimates of physical variables for use in advanced technologies, such as frequency calibr…
Probabilistic Metrology Attains Macroscopic Cloning of Quantum Clocks
B. Gendra, J. Calsamiglia, R. Munoz-Tapia +2
It has been recently shown that probabilistic protocols based on postselection boost the performances of phase estimation and the replication of quantum clocks. Here we demonstrate…
Programmable discrimination with an error margin
G. Sentís, E. Bagan, J. Calsamiglia +1
The problem of optimally discriminating between two completely unknown qubit states is generalized by allowing an error margin. It is visualized as a device---the programmable disc…
Quantum Metrology Assisted with Abstention
B. Gendra, E. Ronco-Bonvehi, J. Calsamiglia +2
The main goal of quantum metrology is to obtain accurate values of physical parameters using quantum probes. In this context, we show that abstention, i.e., the possibility of gett…
Robust optimal quantum learning without quantum memory
G. Sentís, J. Calsamiglia, R. Munoz-Tapia +1
A quantum learning machine for binary classification of qubit states that does not require quantum memory is introduced and shown to perform with the minimum error rate allowed by…
Beating noise with abstention in state estimation
Bernat Gendra, Elio Ronco-Bonvehi, John Calsamiglia +2
We address the problem of estimating pure qubit states with non-ideal (noisy) measurements in the multiple-copy scenario, where the data consists of a number N of identically prepa…
Quantum learning without quantum memory
G. Sentís, J. Calsamiglia, R. Munoz-Tapia +1
A quantum learning machine for binary classification of qubit states that does not require quantum memory is introduced and shown to perform with the very same error rate as the op…
Scavenging quantum information: Multiple observations of quantum systems
Peter Rapcan, John Calsamiglia, Ramon Munoz-Tapia +2
Given an unknown state of a qudit that has already been measured optimally, can one still extract any information about the original unknown state? Clearly, after a maximally infor…
Optimal signal states for quantum detectors
Ognyan Oreshkov, John Calsamiglia, Ramon Munoz-Tapia +1
Quantum detectors provide information about quantum systems by establishing correlations between certain properties of those systems and a set of macroscopically distinct states of…
Multi-copy programmable discrimination of general qubit states
G. Sentís, E. Bagan, J. Calsamiglia +1
Quantum state discrimination is a fundamental primitive in quantum statistics where one has to correctly identify the state of a system that is in one of two possible known states.…
Local discrimination of mixed states
J. Calsamiglia, J. I. de Vicente, R. Munoz-Tapia +1
We provide rigorous, efficiently computable and tight bounds on the average error probability of multiple-copy discrimination between qubit mixed states by Local Operations assiste…
Estimation of quantum finite mixtures
J. I. de Vicente, J. Calsamiglia, R. Munoz-Tapia +1
We consider the problem of determining the weights of a quantum ensemble. That is to say, given a quantum system that is in a set of possible known states according to an unknown p…
Phase estimation for thermal Gaussian states
M. Aspachs, J. Calsamiglia, R. Munoz-Tapia +1
We give the optimal bounds on the phase-estimation precision for mixed Gaussian states in the single-copy and many-copy regimes. Specifically, we focus on displaced thermal and squ…
Phase-Covariant Quantum Benchmarks
J. Calsamiglia, M. Aspachs, R. Munoz-Tapia +1
We give a quantum benchmark for teleportation and quantum storage experiments suited for pure and mixed test states. The benchmark is based on the average fidelity over a family of…