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Enhancement of quantum speed limit time due to cooperative effects in multilevel systems
(IOP Publishing, 2015-08)
Deriving minimum evolution times is of paramount importance in quantum mechanics. Bounds on the speed of evolution are given by the so called quantum speed limit (QSL). In this work we use quantum optimal control methods ...
Entanglement and the ticking of the clock
(Sociedade Brasileira de Física, 2020-06)
The concept of entanglement is at the heart of quantum physics. It plays a central role in all quantum phenomena involving composite systems. Interestingly, there is an intriguing idea that has attracted considerable ...
Entropic characterization of quantum states with maximal evolution under given energy constraints
(Molecular Diversity Preservation International, 2019-08-07)
A measure D[t1, t2] for the amount of dynamical evolution exhibited by a quantum system during a time interval [t1, t2] is defined in terms of how distinguishable from each other are, on average, the states of the system ...
A non-Markovian approach for two dissipative quantum walks
(Springer, 2018-10)
We study the non-Markovian evolution of two free spinless distinguishable particles in a 1D lattice using a completely positive map. The Renewal theory is used to introduce, in a phenomenological way, the concept of disorder ...
Non-unitary evolution of quantum logics
(Springer Science and Business Media, LLC, 2016-05)
In this work we present a dynamical approach to quantum logics. By changing the standard formalism of quantum mechanics to allow non-Hermitian operators as generators of time evolution, we address the question of how can ...
Time-optimal control fields for quantum systems with multiple avoided crossings
(American Physical Society, 2015-10)
We study time-optimal protocols for controlling quantum systems which show several avoided level crossings in their energy spectrum. The structure of the spectrum allows us to generate a robust guess which is time-optimal ...
Quantum histories and correlations in quantum measurements
(Springer, 2018-10)
In this paper, the measurement process is described as an interaction between two quantum systems: the system to be measured and the measuring instrument. The time evolution is determined only by the Schrödinger equation, ...
Evolution of quantum observables: from non-commutativity to commutativity
(Springer, 2020-07)
A fundamental aspect of the quantum-to-classical limit is the transition from a non-commutative algebra of observables to commutative one. However, this transition is not possible if we only consider unitary evolutions. ...