Today the Beeb website carried an article on how plants may be using quantum coherence to improve light harvesting in photosynthesis. You can read it here.
So what do we know?
From our understanding of Physics and the conditions we think determine whether an object operates in the classical/quantum regime, it had been assumed that plants could not sustain quantum states. And so the existence of quantum states/behaviour in plants is big deal. The Science article that the Beeb picks up on is of course not the first to delve into this matter. There has been other research in this area, see refs 1-8 in the Science article. Also you may recall that in my post Monday at Laser world of Photonics I had heard a talk by Nick van Hulst on this very topic!
But why should we care?
Well apart from these findings making us question our understanding of the natural world yet again and opening exciting new investigative journeys, there are huge applications for this in photovoltaics (PV). Renewable energy through solar cells has been a massively important for a number of years and still offers great potential for grid parity and satisfying some of our thirst for electricity. Amongst the issues that dog improvement in PV performance, is how we can cut down on the reflection of sunlight from the solar cell surface, and increase the quantum efficiency or conversion of this energy into electricity.
If we can understand how the absorbed sunlight in plants is transferred to a reaction centre with lower loss and in less time than through classical transport, we may be able to mimic such mechanisms in our solar cells. That would hopefully increase efficiency far beyond what we can achieve today.
Now we may well wonder how easy it would be to transfer such a mechanism of quantum energy transport observed in plants to inorganic structures in say Si solar cells? The answer is I don’t know. But its worth finding out!! And, also if it is more feasible to look to recreate this in organic solar cells though they don’t have proteins like the plants!
Either way I think its tremendously exciting.