One major idea there seems to be that the "environment" (quantum
decoherence) assists or optimizes the transport of a signal
The idea that photosynthetic systems are doing a Grover search or implementing some quantum algorithm, turned out not to be accepted in the community, and while scientists remained too professional to ridicule the original papers of their fellow-scientists in published papers, the opposition to this idea was observed in many many talks at conferences. Eventually it was even published that the quantum coherence in the FMO has no relevance to its photosynthetic function: see "Why quantum coherence is not important in the FMO complex" by Dattani and Wilkins.
Furthermore, decoherence is not optimizing the transfer. Optimizing it would involve searching the space of all possible bath models, all possible couplings to those bath models, all possible bath spectral densities, and all possible models of static disorder, among other things. This is an uncountably infinite space, and finding some optimum transfer rate is a problem too hard even for a quantum computer to solve. To think that the living organism has found a way to transfer the energy optimally is also flawed. Maybe by removing one water molecule there would be less disturbance and the energy transfer would happen 10$^{-22}$ seconds faster, which means the previous configuration that included that water molecule was not optimal.
The environment/bath does assist the energy transfer, because without it you would have infinitely long Rabi oscillations:
By coupling to the bath, we get damped Rabi oscillations that get localized on the lowest-energy site (known as the "sink") which couples to the reaction center that the excitation needs to get to for photosynthesis:
Isn't that beautiful how none of the excitation was getting to the blue site without the bath, but simply by turning on the bath we get a major energy transfer from antenna to reaction center?
All calculations were done in Octave using Nike Dattani's FeynDyn (Feynman Dynamics) code:
1) sudo apt-get install octave
2) git clone https://github.com/ndattani/FeynDyn.git
3) open sampleInput_7x7_FMO_WilkinsDattani_2015_JCTC.m in octave
4) Press F5 and the dynamics with bath pops up after 62 seconds
5) On line 51 make J = 0, for no coupling to bath, press F5 again.
You can change the temperature, spectral density, and Hamiltonian parameters and get slower and faster energy transfer rates, and you will quickly see why the crystal structure parameters used in this simulation are not optimal, and why it is going to be impossible even for a quantum computer to find THE optimal transfer rate.
has this been explored in artificial systems either as quantum computation or in a quantum simulator?
I have explained that the photosynthetic complexes are not "doing quantum computation", even though that was claimed in the early papers of Fleming et al.
However it has been found that with quantum annealing, sometimes the ground state solution is found faster when the temperature is increased: http://convexoptimization.com/TOOLS/manufacturedspins.pdf. Having a noisy environment helps to escape local minima where the annealing process would get trapped if you were at 0 Kelvin. So this is an example of an artificial system that uses this phenomenon, and after thinking about your question all of yesterday and today, it is the only example I could come up with.
