Interplay of electron–phonon coupling, dissipative phonon bath, and electron–electron interaction in a triangular quantum-dot trimer

Nonequilibrium charge transport through a trimer molecular transistor (TMT) composed of three quantum dots arranged in a triangular geometry has been studied in the presence of electron-electron and electron-phonon interactions. The system is described by an extended Anderson-Holstein-Caldeira-Leggett Hamiltonian, where phonon damping arises from coupling to a substrate phonon bath. The electron-phonon interaction is treated nonperturbatively using the Lang-Firsov transformation, while the Coulomb interaction is included at the mean-field level. Using the Keldysh nonequilibrium Green's function (NEGF) formalism, we compute the spectral function, current, and differential conductance. Our results reveal how Coulomb repulsion, polaronic renormalization, and dissipation jointly influence transport through the triangular molecular transistor.