Demos.ConicalInter.Warping
Quadratic E x e Jahn-Teller system: Warped potentials
If quadratic Jahn-Teller coupling (g ≠ 0) is added to the spin boson system, the circular symmetry of the system is broken. The corresponding (adiabatic) potential energy surfaces become deformed ("warped") and the ground state exhibits threefold rotational symmetry with three additional conical intersections. The lower potential surface exhibits an alternating sequence of three minima and three saddles.
For the example chosen here (κ=10, ω=5, g=1), the energy of the minima and saddles lies at -12.5 and at -8.0, respectively. The corresponding radial coordinates are 2.5 (minima) and 1.67 (saddles). One conical intersection (with first excited state; not shown) can be found at ρ=0, the other three intersections at ρ=2κ/g=20 are far outside the range of the plots below.
k = 0
The wavepacket chosen here strongly resembles a ground vibrational states in one of the three wells. Its energy is so low that it practically doesn't interact with the other minima, i.e. tunneling is negligible.
k = 5
The wavepacket chosen here has enough energy to surmount the saddles separating neighbouring wells. On the long run, there will be strong dispersion, and the wavefunction will become delocalized among the three symmetry-equivalent wells.
