Rajani, K.V.Ahmed Rizwan, C.L.A.Naveena Kumara, A.N.Vaid, D.Ajith, K.M.2026-02-052020Nuclear Physics B, 2020, 960, , pp. -5503213https://doi.org/10.1016/j.nuclphysb.2020.115166https://idr.nitk.ac.in/handle/123456789/23640We investigate the thermodynamic phase transition and heat engine efficiency in regular Bardeen AdS black hole. The thermodynamics of the black hole is analyzed in extended phase space. A first order phase transition analogous to van der Waal system is evident from this study, which is affirmed by the specific heat divergence at the critical points. A conventional heat engine is constructed by considering the black hole as working substance. The efficiency is obtained via a thermodynamic cycle in the P?V plane, which receives and ejects heat. The heat engine efficiency is improved by adding a quintessence field. The analytical expression for heat engine efficiency is derived in terms of quintessence dark energy parameter. © 2020 The Author(s)