Conceptual question on wave-particle duality (electron microscope)

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Discussion Overview

This discussion revolves around the concept of wave-particle duality, specifically in the context of electron microscopes and the comparison with using high-energy electromagnetic radiation such as x-rays or gamma rays for imaging. Participants explore the implications of using electrons versus photons for achieving high resolution in microscopy.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants note that electrons exhibit wave-like properties, with wavelength inversely related to momentum, which allows for high-resolution imaging in electron microscopes.
  • One participant questions why electrons are necessary, suggesting that high-energy electromagnetic radiation could theoretically achieve similar resolution.
  • Another participant points out practical challenges in using x-rays and gamma rays, such as difficulties in focusing high-energy EM radiation and potential damage to samples.
  • Concerns are raised regarding the high energy of photons at short wavelengths, which could vaporize or damage specimens, while electrons, despite having higher energy, may interact differently with materials.
  • Some participants discuss the interaction effects between photons and charged particles, suggesting that the nature of these interactions could influence the choice of imaging method.
  • There is mention of the ability to focus electrons using magnets, which is presented as an advantage over the challenges associated with focusing x-rays and gamma rays.
  • A later reply emphasizes that while x-rays can be focused using specialized techniques, they are not easily generated at specific frequencies and pose safety management issues.

Areas of Agreement / Disagreement

Participants express differing views on the practicality and effectiveness of using x-rays and gamma rays compared to electrons for high-resolution imaging. There is no consensus on the best approach, and the discussion remains unresolved regarding the optimal method for achieving high resolution in microscopy.

Contextual Notes

Limitations include the dependence on specific conditions for focusing high-energy radiation and the unresolved nature of the interaction effects between photons and charged particles. The discussion also highlights the complexities involved in generating and managing high-energy electromagnetic radiation.

AStaunton
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according to wave particle duality particles such as electrons exhibit wave like properties.
and the wavelngth is given by lambda=h/p, so increase momentum and get shorter lambda.

This property is utilised in the electron microscope to get very short wavelengths and so have very high resolution when looking at specimens.

My question is, why do they need electrons to do this? why not just shine electromagnetic radiation of very short wavelength (eg x-rays or gamma rays) on the specimen to get equally sharp resolution?
 
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AStaunton said:
according to wave particle duality particles such as electrons exhibit wave like properties.
and the wavelngth is given by lambda=h/p, so increase momentum and get shorter lambda.

This property is utilised in the electron microscope to get very short wavelengths and so have very high resolution when looking at specimens.

My question is, why do they need electrons to do this? why not just shine electromagnetic radiation of very short wavelength (eg x-rays or gamma rays) on the specimen to get equally sharp resolution?

Because at those very short wavelength, the energy of each photons can be so high, it would either vaporize, or cause damage to your sample. Furthermore, you also have issues with penetration depth.

Zz.
 
You are correct that we would be able to get high resolution images of objects using x-rays and gamma rays in theory. In practice, however, it is difficult to focus high energy EM radiation (it tends to destroy any type of lens we put into the optical path). So, while we can collect diffraction information (which does contain the high resolution information of the sample, this is how crystallography works), we cannot produce an image without a way to refocus the light.

Electrons are convenient because they can be focused using magnets.
 
ZapperZ said:
Because at those very short wavelength, the energy of each photons can be so high, it would either vaporize, or cause damage to your sample.
The energy of an electron with the same wavelength is even higher.

I believe the true reason might be the fact that the interaction effects between a photon and a unit charge are proportional to alpha=1/137, while the interaction effects between two unit charges are proportional to alpha^2 which cause a much smaller damage.
 
Demystifier said:
The energy of an electron with the same wavelength is even higher.

I believe the true reason might be the fact that the interaction effects between a photon and a unit charge are proportional to alpha=1/137, while the interaction effects between two unit charges are proportional to alpha^2 which cause a much smaller damage.

No, I think Ygggdrasil has given a more relevant/practical reasons why.

Zz.
 
Ygggdrasil said:
You are correct that we would be able to get high resolution images of objects using x-rays and gamma rays in theory. In practice, however, it is difficult to focus high energy EM radiation (it tends to destroy any type of lens we put into the optical path). So, while we can collect diffraction information (which does contain the high resolution information of the sample, this is how crystallography works), we cannot produce an image without a way to refocus the light.

Electrons are convenient because they can be focused using magnets.
Yes, the problem is in focusing X-rays and gamma rays, but not exactly because they tend to destroy the lens; I'd say instead it's because lenses doesn't focuse x-gamma rays at all (very complicated metal surfaces can be used to focus x-rays by high-incidence reflection).
Furthermore those rays are not very easy to generate at a specified frequency, and are not easy to manage for human safety.
 

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