Saved in:
Bibliographic Details
Main Authors: Avella, Victor Gonzalez, Vargas, Abraham Vega, Vergara, Tomas Merlo, Doria, Kevin de la Ossa, Czartowski, Jakub, Main, Dougal, Araneda, Gabriel, Delgado, Aldo, Goyeneche, Dardo
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2510.16117
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909854236409856
author Avella, Victor Gonzalez
Vargas, Abraham Vega
Vergara, Tomas Merlo
Doria, Kevin de la Ossa
Czartowski, Jakub
Main, Dougal
Araneda, Gabriel
Delgado, Aldo
Goyeneche, Dardo
author_facet Avella, Victor Gonzalez
Vargas, Abraham Vega
Vergara, Tomas Merlo
Doria, Kevin de la Ossa
Czartowski, Jakub
Main, Dougal
Araneda, Gabriel
Delgado, Aldo
Goyeneche, Dardo
contents We present two scalable and entanglement-free methods for estimating the collective state of an n-qubit quantum computer. The first method consists of a fixed set of five quantum circuits-regardless of the number of qubits-that avoid the use of entanglement as a measurement resource, relying instead on classical communication between selected pairs of qubits. The second method requires only 2n+1 circuits, each of which applies a single local gate to one of the n qubits during the measurement stage. Unlike traditional estimation methods, our approaches do not require any costly post-processing procedure to estimate a quantum state, enabling scalability to relatively large system sizes. We experimentally compare both methods on freely available IBM quantum processors, and observe how the state estimation varies with increasing number of qubits and shots. We further validated our results by estimating the 4-qubit entangled state of two remote ion-trap quantum processors, demonstrating that the optimized 2n+1 tomographic scheme achieves estimates consistent with standard methods while using exponentially fewer measurements.
format Preprint
id arxiv_https___arxiv_org_abs_2510_16117
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Efficient state estimation on quantum processors
Avella, Victor Gonzalez
Vargas, Abraham Vega
Vergara, Tomas Merlo
Doria, Kevin de la Ossa
Czartowski, Jakub
Main, Dougal
Araneda, Gabriel
Delgado, Aldo
Goyeneche, Dardo
Quantum Physics
We present two scalable and entanglement-free methods for estimating the collective state of an n-qubit quantum computer. The first method consists of a fixed set of five quantum circuits-regardless of the number of qubits-that avoid the use of entanglement as a measurement resource, relying instead on classical communication between selected pairs of qubits. The second method requires only 2n+1 circuits, each of which applies a single local gate to one of the n qubits during the measurement stage. Unlike traditional estimation methods, our approaches do not require any costly post-processing procedure to estimate a quantum state, enabling scalability to relatively large system sizes. We experimentally compare both methods on freely available IBM quantum processors, and observe how the state estimation varies with increasing number of qubits and shots. We further validated our results by estimating the 4-qubit entangled state of two remote ion-trap quantum processors, demonstrating that the optimized 2n+1 tomographic scheme achieves estimates consistent with standard methods while using exponentially fewer measurements.
title Efficient state estimation on quantum processors
topic Quantum Physics
url https://arxiv.org/abs/2510.16117