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Article by INAOE researchers is recognized as Editor's Pick in the prestigious magazine Optics Letters

The article “Exact solution for the interaction of two decaying quintizied fields” by researchers from the INAOE Quantum Optics Group, was selected as the “Editor’s Pick” of the magazine Optics Letters.
The article was published on October 13. The authors are Leonardi Hernández Sánchez, a doctoral student at INAOE, and doctors from the Iran Optics Coordination Ramos Prieto, Francisco Soto Eguibar and Héctor Moya Cessa.

Optics Letters magazine is one of the most prominent publications in the area worldwide. The fact that the article has been selected as Editor's Pick demonstrates the relevance of this theoretical work, which is part of Leonardi Hernández Sánchez's doctoral thesis.
Below is a summary of the work:
Open systems are those in which the particular system to be described interacts with its environment (its surroundings). To describe open systems in quantum theory, a master equation is used, which is the equivalent of the Schrödinger equation for closed systems. However, solving the master equation is extremely complicated, and usually requires making assumptions and approximations to simplify it. There are two main assumptions that have to be made: a) assume that the entire system, that is, the combination of the particular system under study and the environment, is a large closed system, and b) assume that the state of the system in the next instant depends only on the current state of the system; in other words, assume that the system has no memory of previous states. This last assumption is known as the Markovian approximation. With these assumptions the master equation can be reduced to a simpler equation, known as the Lindblad equation.
In this work we show that the Markovian dynamics of two coupled harmonic oscillators can be analyzed using a Schrödinger equation and an effective non-Hermitian Hamiltonian. This is achieved through a non-unitary transformation involving superoperators; Such a transformation allows the elimination of quantum jump superoperators, making it possible to write the master Lindblad equation in terms of an equation similar to the von Neumann equation, with an effective non-Hermitian Hamiltonian. This reframing of the problem can be generalized to an arbitrary number of interacting fields. Finally, by applying an additional non-unitary transformation, the effective non-Hermitian Hamiltonian can be diagonalized to obtain the evolution of any input state in a fully quantum domain.