Spontaneous synchronization in spin systems

This Master Thesis is focused on the study of the fundamental properties that a system must

possess to be able to show synchronization in the quantum regime. In the article “Synchronizing

the Smallest Possible System” [1] it was claimed that quantum two-level systems are not a good

candidate, as they lack a limit cycle and cannot be seen as self-sustained oscillators, therefore the

smallest system to be a three-level system.

Our intention is to raise objections to this idea using two main arguments. First, we start ques-

tioning the definition of the limit cycle proposed in this article, as well as the premise that only

systems with a limit cycle can be synchronized. And secondly, we point out that the quantum

features observed in the article “Synchronization and Entanglement Generation” [2], in which the

same authors submit the spontaneous synchronization between two coupled spins s = 1 systems,

can be replicated with a pair of spin s = 1/2 systems, emphasizing the similarity between both systems.

We analyse the evolution of the spin observables using different measures of synchronization.

[1] Roulet and Bruder, Phys. Rev. Lett., 121, 053601 (2018)

[2] Roulet and Bruder, Phys. Rev. Lett., 121, 063601 (2018)

Jury: Rosa López, Miguel C. Soriano, Gian Luca Giorgi

Advisors: Gian Luca Giorgi, Roberta Zambrini

Zoom:  https://uibuniversitat.zoom.us/j/88073638068