Entanglement and dynamical scaling laws in quantum superabsorption

Quantum batteries (QBs) exploit collective quantum resources to surpass the limits of classical energy storage and power delivery. We analyze N -qubit cavity-coupled QBs governed by Dicke and Tavis-Cummings models under Gaussian driving and open-system dynamics. Finite-size scaling laws O ( N ) ∼ N α demonstrate an optimal region of relaxation and dephasing where coherent driving stabilizes entanglement entropy growth for thermodynamic observables (maximum energy E max , charging time τ , and maximum power P ¯ max ) and for qubit and cavity entanglement entropies. The Dicke model exhibits entropy-suppressed extensive behavior, while the Tavis-Cummings model achieves superextensive scaling with α E max ∈ [ 1.08 , 1.26 ] , α τ ≈ − 0.49 , and α P ¯ max ∈ [ 1.57 , 1.73 ] , supported by qubit-cavity entanglement. We demonstrate that dissipation can act as a stabilizer source, yielding scaling benchmarks that are relevant to several experimental platforms. Our findings connect entanglement, dissipation-enhanced scaling laws, and superabsorption, outlining a pathway toward scalable quantum batteries offering practical quantum advantage.