Heisenberg's error-disturbance relations: a joint measurement-based experimental test

TL;DR

This paper introduces a novel experimental method using quantum walks to test Heisenberg's error-disturbance relations for qubits, focusing on joint measurements of observables and establishing a new universally valid relation.

Contribution

It proposes and demonstrates an extendible quantum walk-based method for joint measurements and tests a new universally valid error-disturbance relation for three observables.

Findings

Validated the new error-disturbance relation experimentally

Developed an extendible quantum walk-based measurement technique

Provided evidence for the fundamental nature of the new relation

Abstract

The Heisenberg's error-disturbance relation is a cornerstone of quantum physics. It was recently shown to be not universally valid and two different approaches to reformulate it were proposed.The first one focuses on how error and disturbance of two observables, A and B, depend on a particular quantum state. The second one asks how a joint measurement of A and B affects their eigenstates. Previous experiments focused on the first approach. Here, we focus on the second one. Firstly, we propose and implement an extendible method for quantum walk-based joint measurements of noisy Pauli operators to test the error-disturbance relation for qubits. Then, we formulate and experimentally test a new universally valid relation for the three mutually unbiased observables. We therefore establish a fundamentally new method of testing error-disturbance relations.