Laser and nano-holes experiment

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Discussion Overview

The discussion revolves around a proposed optical experiment involving a 1cm² aluminum substrate with a matrix of nano-holes and the effects of a focused laser on this setup. Participants explore the implications of using different laser powers and the potential for optical transmission through nano-holes, addressing both theoretical and practical aspects of the experiment.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant proposes an experiment involving a 1W laser focused on a matrix of nano-holes in an aluminum substrate, suggesting that the energy produced is undetectable by conventional sensors.
  • Another participant challenges the claim that no optical transmission is possible through the nano-holes, stating that attenuation increases with size but is never complete.
  • A participant questions the dimensions of the proposed setup, noting that the area illuminated by the laser may not correspond to the claimed size of the disk and asks for clarification on the experiment's objectives.
  • One participant references the concept of extraordinary optical transmission as potentially relevant to the discussion.

Areas of Agreement / Disagreement

Participants express differing views on the possibility of optical transmission through the nano-holes, with some asserting it is impossible while others argue against this notion. The discussion remains unresolved regarding the effectiveness of the proposed experiment and the validity of the initial claims.

Contextual Notes

There are uncertainties regarding the assumptions made about the laser's power and the geometry of the nano-holes, as well as the definitions of terms used in the discussion. The mathematical calculations presented are not fully verified within the thread.

James_AA
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TL;DR
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?
 
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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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