We apply a computationally-efficient method to study the superradiant evolution of a set of N two-level systems spontaneously radiating under the effect of phase-breaking mechanisms . We investigate the dynamics generated by non-radiative losses and pure dephasing, and their interplay with spontaneous emission, comparing the exact method to analytical approximations.
The computationally-efficient tool can solve in general the dynamics of large ensembles of N two-level systems evolving under the action of local Lindblad dissipation terms that are permutational invariant [2-5]. The method keeps the computational resources scaling as O(N^2) instead of having them grow exponentially like 2^(2N). I will discuss how this
implementation relates to several other works that are exploiting permutational invariance to reduce the resources of simulation [6-8]. The code is written in Python and readily available for use in other phenomena, such as spin squeezing and phase transitions.
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