Direct modification of polariton ground states, can be caused by two other physical processes: 1,9,29 (i) off-resonance light-matter interactions (third term in Eq. 2) through the ground state permanent dipole and optical transition dipoles between the ground and excited states, and (ii) a dipole selfenergy (DSE) term (final term in Eq. 2). For example, in (i), |ψ g , 0⟩ will couple to |ψ g , 1⟩ state through a term proportional to ⟨ψ g , 0|μ(â † + â)|ψ g , 1⟩ = µ gg ⟨0|(â † + â)|1⟩ = µ gg , and |ψ g , 1⟩ will couple to |ψ e , 0⟩ through ⟨ψ e , 0|μ(â † + â)|ψ g , 1⟩ = µ ge ⟨0|(â † + â)|1⟩ = µ ge . Note that there may be many such electronic excited states ψ e that contribute to the ground state through these off-resonant interactions (See Supporting Information for details on specific interaction terms depicted through an analysis of the ground state density matrix). In (ii), the DSE term allows for extensive coupling through the square of the electronic dipole matrix ( μ • ê) 2 ≡ μ2 where we denote μ as the projection of μ along the cavity polarization direction ê. The matrix elements between the ground state |ψ g ⟩ and any electronic state |ψ α ⟩ due to the DSE coupling can be expressed as ⟨ψ g |μ 2 |ψ α ⟩ = γ µ gγ µ γα , where α and γ include the ground and excited electronic states. The direct coupling (i) is responsible for the accumulation of photons in the ground state while DSE (ii) is largely responsible for the modifications to the ground state energy. The polariton eigenstates and eigenenergies are obtained by solving the following equation