Optimal quantum resource generation by coupled transmons immersed in Markovian baths
Tanaya Ray, Ahana Ghoshal, Debraj Rakshit, Ujjwal Sen · Physical Review A · 2023
We analyze quantum resource generation of capacitively coupled multilevel transmon circuits surrounded by bosonic baths, within the Markovian limit. Superconducting circuit elements are in practice usually part of a larger circuit, constructed with many other elements, which along with their environment is assumed to be mimicked by the baths. We study the response, to variation of the temperature of the thermal baths and the coupling strength, of resource generation for the system prepared in zero-resource initial states. We focus, in particular, on entanglement and quantum coherence as resources. We find that capacitive coupling, even if weak, can compete with Markovian decay of quantum resources and lead to significant steady-state values of the same. At short and moderate timescales, the resources exhibit nonmonotonic oscillatory behavior, reminiscent of the same in non-Markovian environs in absence of intrasystem coupling. We quantify the entanglement generation power of coupled transmon qutrits, taking into account the maximum entanglement the system can generate and the timescale over which the system can sustain a significant amount of the same. We identify the optimal initial separable states leading to maximum entanglement generating power.