RE: FW: A Quantum-Thermodynamic Ratchet For Photonic Frequency Up-Pumping?

I continue to puzzle over Bill's "cheaper-&-cleaner-&-more abundant electricity for everyone" challenge-to-Inventors — currently 'aided' (entirely legally — physician's orders! :)) by the modern version of the traditional opium-eater's favorite ingestible. :) [Dr. Nikolic admonishes me to comply completely with "the doctor's orders" along these lines — which call for remarkably heavy-&-frequent dosings -- so please do blame him entirely for this missive! :)J

In order to generate the maximum voltage-current product from a given area of (single-composition) semiconductor illuminated with a given flux, it's clearly desirable to have monochromatic radiation that's 'matched' to the bandgap, n- &-p Fermi levels, etc. of the chosen semiconductor. However, what God gives us — in generous total quantities, if not pleasantly high fluxes :) -- is a —0.5 eV Planckian spectrum with a batch of holes chewed in it, i.e., the solar spectrum at AM1, for which the maximum-attainable energy conversion efficiency is widely believed to be 50.5.

Even these performance levels are attained only with a half-dozen p-n junction artfully (i.e., very expensively) 'stacked' on each other, each taking its bandgap-designated 'bite' from the incoming radiation (and thus being semi-insanely expensive, even for USG purposes) — cf. appended Figure. It clearly would be greatly preferable to have a large fraction of the energy of the solar spectrum 'presented' to a suitable photovoltaic converter-assembly after being 'transfigured' to single-energy (e.g., —2.5 eV) photons.

So what are the basic prospects for usefully — i.e., practically -- monochromatizing the AM1 solar spectrum in the photovoltaic context?

These prospects would seem to be of non-trivial magnitudes — at least to me-in-present condition! — as suggested by the appended items (which 'connection' is admittedly somewhat distant)?

Molecular quantum oscillators can have very high Qs in/about the visible optical spectrum, e.g., 106, when they're in vacuum-type circumstances, i.e., are 'natural linewidth'-constrained. However, these Qs can be depressed by as much as —4 orders-of-magnitude, e.g., via collisional interactions in normal (zero-P, non-resonant) media.

So, what can we do with sets-of-(preferably, high-Q molecular) oscillators 'physically-&-spectrally associated' with each other in a suitably engineered environment (seemingly likely enabled by contemporary lithographic capabilities, which already offers minimum features sizes most of an order-of-magnitude smaller than visible spectral wavelengths of interest)?

We would presumably arrange these molecular assemblies in stacks of planar sheets of 'unit cells' containing something of the order of a dozen high-oscillator strength transitions (perhaps carried on something like a half-dozen well-chosen free-space molecules wavelength. — or quantum dots?) which would together 'cover' the AM1 spectrum between, say, 0.5 and 1.5 microns

These would serve to 'harvest' most all of the inputted solar radiation over this —1.6 octave-width spectral band and then make it available for re-radiation by a 'master molecular oscillator located proximate to the 'unit cell' to whose upper-level they would each be (chosen to) be chosen to couple by short-range non-radiative energy transfer while concurrently making an 'energy contribution' of the order of a few kT to the local medium — so as to helpfully make up energy differences between the two donating quantum oscillators and the donated-to one and (not quite incidentally) to confer a degree of thermodynamic irreversibility onto the energy transfer process.

The donated-to molecule then fluoresces the up-pumped (in the frequency sense) quantum energy with high quantum efficiency — helpfully conferred by lack-of-competing de-excitations in its surroundings, e.g., the energy-going-uphill inability to effectively back-transfer its excitation to adjacent donating molecules.

These up-pumped, quasi-monochromatic photons are then 'inputted' (via device-internal reflectors, etc. aimed at optical transfer efficiency optimization) to a photovoltaic conversion section of the device.

Yes, of course I also have-in-mind the analogous photochemical trick, in which we convert such 'spectrally-enhanced sunlight' into high-energy chemical bond-rearrangements, e.g., energy efficiency-enhanced photosynthesis! :)

photosynethes seems to work by not needing the particle at all , but the reacting to its wave nature, . the light should be able to be tuned. and not one gap but many being activated by the same photon

Oh Lord.

This is a very hard problem — do you have any interesting inputs to add here?

yes „ photosynthesis 8-90 % efficient. „ it acts becasue of the wave nature of light, this isthe next frontier.

That's true.

How many gaps do you think could be activated by one photon?

Just curious do you think that in our lifetimes we will have any energy breakthroughs?

8-90% seems like a broad range?

Maybe a typo.