Abstract
In quantum mechanics, predictions are made by way of calculating expectation values of observables, which take the form of Hermitian operators. Non-Hermitian operators, however, are not necessarily devoid of physical significance, and they can play a crucial role in the characterization of quantum states. Here we show that the expectation values of a particular set of non-Hermitian matrices, which we call column operators, directly yield the complex coefficients of a quantum state vector. We provide a definition of the state vector in terms of measurable quantities by decomposing these column operators into observables. The technique we propose renders very-large-scale quantum states significantly more accessible in the laboratory, as we demonstrate by experimentally characterizing a 100,000-dimensional entangled state. This represents an improvement of two orders of magnitude with respect to previous phase-and-amplitude characterizations of discrete entangled states.
Original language | English |
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Article number | 10439 |
Journal | Nature Communications |
Volume | 7 |
DOIs | |
Publication status | Published - 19 Jan 2016 |
ASJC Scopus subject areas
- General Biochemistry,Genetics and Molecular Biology
- General Chemistry
- General Physics and Astronomy
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Jonathan Leach
- School of Engineering & Physical Sciences - Professor
- School of Engineering & Physical Sciences, Institute of Photonics and Quantum Sciences - Professor
Person: Academic (Research & Teaching)