I Laser and nano-holes experiment

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The discussion centers around an optical experiment involving a 1cm² aluminum substrate with a matrix of nano-holes and a focused 1W laser. The proposal argues that the laser's output, when calculated over the nano-hole area, results in an undetectable power level of 0.1 nanowatts, which is below the sensitivity threshold of conventional sensors. Participants challenge the assumptions about optical transmission through subwavelength holes, suggesting that some transmission is possible despite the proposed limitations. There are also considerations about using higher power lasers or LEDs to achieve detectable results. The conversation highlights the complexities of optical experiments at the nanoscale and the need for clarity in experimental design.
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TL;DR Summary
An optical experiment is proposed to validate points
Hi everyone, let me propose an experiment to see if you agree with my points. There is a 1cm2 1-micron thick aluminum substrate with a matrix of 100x100 nano-holes each with 100x100nanometers cross section separated by 100nanometers. Then, we focus a 1W laser with visible wavelength:
drawing.jpg

1- UNDETECTABLE:

The matrix of nan-holes is equivalent to a square of 10,000x10,000nm which is a surface of 1E08nm2 = 1E-010m2

The 1W laser produces 1J per second which is 1 kg⋅m2⋅s−3 in the calculated surface of 1E-010m2 equals to 1E-010J= 0.1 nanowatts.

So, even assuming total transmission, such 0.1 nanowatts are undetectable by conventional high sensitivity optical power sensors (normally, 10nW minimum detectable power).

2-ALTERANTIVE:

A 5W laser is used for non-industrial laser cutting so to avoid burning the 1-micron substrate, 1W was chosen. However, even increasing the power to 4W would still make it undetectable. A solution could be using a 100W high power LED plus some lenses. Or even the following 1,500W LED:

[Spammy link deleted by the Mentors]

3-POINTLESS:

Being nano-holes at the subwavelength scale of light, no optical transmission is posible.

So, thanks for reading and let me know your thoughts.
 
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James_AA said:
TL;DR Summary: An optical experiment is proposed to validate points

Being nano-holes at the subwavelength scale of light, no optical transmission is posible.
Where did you get that idea from? The attenuation of a small hole increases with size but it is never complete.
James_AA said:
TL;DR Summary: An optical experiment is proposed to validate points

The 1W laser produces 1J per second which is 1 kg⋅m2⋅s−3
and could you walk me through that one?
 
James_AA said:
TL;DR Summary: An optical experiment is proposed to validate points

Hi everyone, let me propose an experiment to see if you agree with my points. There is a 1cm2 1-micron thick aluminum substrate with a matrix of 100x100 nano-holes each with 100x100nanometers cross section separated by 100nanometers. Then, we focus a 1W laser with visible wavelength:
Your array only spans (100* 200nm) = 20 microns, not 1 cm, so your disk is mostly solid and nontransmissive. What area of the disk is illuminated by your 'focused' laser beam? What "optical experiment" are you proposing, and what "points" are you trying to validate?
 
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