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material
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In anomalously dispersive media, the change in phase velocity with wavelength is negative; that is dv/dλ < 0.
I wanted to ask:
(a) whether you could fit a wide range of frequencies into a resonant cavity by taking advantage of anomalous dispersion
(b) whether a material like this exists for the 300nm < λ < 1100nm range and
(c) whether it exhibits the behaviour of n = λο/λd,
where n = index of refraction, λο = wavelength between 300 and 1100nm, and λd = desired wavelength to design the resonant cavity with λd = 300nm.
(d) whether you could design the resonant cavity so that light goes in but doesn't escape easily because of the waveguide modes and because of total internal reflection characteristics.
I am thinking if you could etch tiny rectangular cavities filled with the right medium on the surface of a silicon solar cell and focus the surrounding light into the cavity, then more of the light will be absorbed by the silicon.
What my maths thinking is:
fo=c/λο, c=300Mm/s
v=fo*λd, v = phase velocity
if λd=300nm,
@ λο=300nm, fo=c/λο=1PHz, v=fo*λd=300Mm/s => n=c/v=1
@ λο=1100nm, fo=c/λο=0.272PHz, v=fo*λd=81.82Mm/s =>n=c/v=3.667
I wanted to ask:
(a) whether you could fit a wide range of frequencies into a resonant cavity by taking advantage of anomalous dispersion
(b) whether a material like this exists for the 300nm < λ < 1100nm range and
(c) whether it exhibits the behaviour of n = λο/λd,
where n = index of refraction, λο = wavelength between 300 and 1100nm, and λd = desired wavelength to design the resonant cavity with λd = 300nm.
(d) whether you could design the resonant cavity so that light goes in but doesn't escape easily because of the waveguide modes and because of total internal reflection characteristics.
I am thinking if you could etch tiny rectangular cavities filled with the right medium on the surface of a silicon solar cell and focus the surrounding light into the cavity, then more of the light will be absorbed by the silicon.
What my maths thinking is:
fo=c/λο, c=300Mm/s
v=fo*λd, v = phase velocity
if λd=300nm,
@ λο=300nm, fo=c/λο=1PHz, v=fo*λd=300Mm/s => n=c/v=1
@ λο=1100nm, fo=c/λο=0.272PHz, v=fo*λd=81.82Mm/s =>n=c/v=3.667