6533b85ffe1ef96bd12c116b

RESEARCH PRODUCT

Influence of dissipation on the extraction of quantum states via repeated measurements

Kazuya YuasaKazuya YuasaAntonino MessinaBenedetto MilitelloHiromichi Nakazato

subject

PhysicsQuantum PhysicsSettore FIS/02 - Fisica Teorica Modelli E Metodi MatematiciQuantum decoherenceIdeal (set theory)spin systemsSpinsquantum measurementFOS: Physical sciencesDissipationSettore FIS/03 - Fisica Della MateriaAtomic and Molecular Physics and OpticsClassical mechanicsQuantum stateQuantum systemstate manipulationQuantum Physics (quant-ph)Spin-½Boson

description

A quantum system put in interaction with another one that is repeatedly measured is subject to a non-unitary dynamics, through which it is possible to extract subspaces. This key idea has been exploited to propose schemes aimed at the generation of pure quantum states (purification). All such schemes have so far been considered in the ideal situations of isolated systems. In this paper, we analyze the influence of non-negligible interactions with environment during the extraction process, with the scope of investigating the possibility of purifying the state of a system in spite of the sources of dissipation. A general framework is presented and a paradigmatic example consisting of two interacting spins immersed in a bosonic bath is studied. The effectiveness of the purification scheme is discussed in terms of purity for different values of the relevant parameters and in connection with the bath temperature.

https://dx.doi.org/10.48550/arxiv.0706.2111