Work

How to detect qubit-environment entanglement generated during qubit dephasing

Year: 2019

Type: article

Abstract: We propose a straightforward experimental protocol to test whether qubit-environment entanglement is generated during pure dephasing of a qubit. The protocol is implemented using only measurements and operations on the qubit---it does not involve the measurement of the system-environment state of interest, but the preparation and measurement of the qubit in two simple variations. A difference in the time dependencies of qubit coherence between the two cases testifies to the presence of entanglement in the state of interest. Furthermore, it signifies that the environment-induced noise experienced by the qubit cannot be modeled as a classical stochastic process independent of the qubit state. We demonstrate the operation of this protocol on a realistically modeled nitrogen-vacancy center spin qubit in diamond interacting with a nuclear spin environment, and show that the generation of entanglement should be easily observable in this case.

Source: Physical Review A

DOI: 10.1103/physreva.100.022318

Authors: Katarzyna Roszak, Damian Kwiatkowski, Łukasz Cywiński

Institutions: Wrocław University of Science and Technology, Czech Academy of Sciences, FZU - Institute of Physics of the Czech Academy of Sciences, Institute of Physics, Polish Academy of Sciences

Language: English

Topic: Quantum Information and Cryptography

Subfield: Artificial Intelligence

Field: Computer Science

Domain: Physical Sciences

Open Access status: green

Funder: Narodowe Centrum Nauki

Award: G8804770086