What is the limit of electron flow in a transistor at 508 GHz?

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Discussion Overview

The discussion revolves around the limits of electron flow in transistors operating at high frequencies, specifically at 508 GHz. Participants explore concepts related to electron behavior, the implications of high-frequency operation on current flow, and the potential need for new materials and theories to manage such frequencies.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants question whether there is a frequency at which electrons do not flow effectively, particularly at very high frequencies.
  • There is a discussion about the nature of electron flow, with some suggesting it is akin to a river flowing from high to low ground, while others emphasize the role of fields in propagating current.
  • One participant notes that the fastest switching transistor reported operates at 508 GHz, referencing a breakthrough at 410 GHz and speculating on the feasibility of surpassing this barrier.
  • Concerns are raised about the behavior of electrons at high frequencies, including whether they would vibrate in AC circuits or if they would behave more like waves.
  • Some participants highlight the concept of skin effect, which affects how currents are localized in wires at high frequencies, and suggest that this could limit the effectiveness of traditional materials like copper.
  • There are mentions of the need for exotic materials and designs to handle frequencies beyond what copper can manage.
  • Questions are posed about the quantum mechanical aspects of electron behavior in conductors and whether classical descriptions remain adequate at high frequencies.
  • One participant introduces the idea of diamond-reinforced composite wire as a potential solution for high-frequency applications.
  • A humorous suggestion of using tachyon beams is also made, indicating a playful exploration of unconventional ideas.

Areas of Agreement / Disagreement

Participants express a range of views on the behavior of electrons at high frequencies, with no clear consensus on the implications or solutions. The discussion remains unresolved regarding the exact nature of electron flow and the limitations imposed by current materials and theories.

Contextual Notes

Participants reference various concepts from classical and quantum physics, indicating that the discussion may involve assumptions about the applicability of these theories at high frequencies. There is an acknowledgment of limitations in current understanding and the potential need for new theoretical frameworks.

Who May Find This Useful

This discussion may be of interest to those studying semiconductor physics, electrical engineering, and materials science, particularly in the context of high-frequency applications and the development of new technologies.

JGM_14
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Is there a frequency at which electrons do not flow (too high freq.)?
Fastest switching transistor- 508 Ghz
 
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Electrons flow as in assuming Newtonian mechanics in quantum space?
Or in wires?
What do you mean by flow?
 
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i figue JGM means by current flowing through circuits...
if so, this is governed by the slowest device in the circuit...
however...this article shows a speed breakthrough at 410GHz...
http://www.sciencedaily.com/releases/2008/02/080207123348.htm

I'd like to think that they could break this barrier but maybe only at high costs...

the research is concentrating in these areas now for the purpose of producing terahertz circuits and waves...and require a whole new mode of transmission line theory and materials...

i'm sure there is a point when the electron becomes more like a wave in the material and so technically...that would be raising the roof of possibilities...bearing in mind that electrons already travel at 'near the speed of light' in regular copper anyway...
 
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the switching of the direction of the current in the wires becomes too fast so the electrons would not vibrate as in AC
Is it possible to happen at frequencies that super high?
 
flow as in electrons migrate from negative to positive, much in the way a river flowes from high ground to low ground the wires being the path that facilitates the water movement the low ground being the positive and the high ground the negative
 
JGM_14 said:
the switching of the direction of the current in the wires becomes too fast so the electrons would not vibrate as in AC
Is it possible to happen at frequencies that super high?
If I remember correctly, an accumulation of charge inside a metal lasts less than about 10^(-15) s; it means we should go up to at least 10^15 Hz with frequency, that is to visible wavelenghts.
 
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So the wire would "glow" at that high of frequency, or would photons not be emitted?
 
I seem to recall that electrons actually diffuse very slowly in conductors, it's the fields that propagate quickly and nudge the electrons along the way ... wires are a long skinny sea of electrons that work more like an inside out waveguide rather than a copper water pipe. A particular electron doesn't ever get to go very far or very fast in a wire. Anyway, it's all kinda Newtonian whereas reality is more quantum. And then there is skin effect, which keeps currents (the electrons that get to participate in the propagation) very localized at high freqs. This dominates wires up to a gig or so, above that the dielectric losses make things worse. So I don't expect to see glowing wires anytime soon, except the kind that Edison made a while back.
 
JGM_14 said:
So the wire would "glow" at that high of frequency, or would photons not be emitted?
The material would become insulating because it's as if the electrons couldn't move freely, however the classical description wouldn't be adequate anylonger and you should use the quantum one.
 
  • #10
for those frequencies that copper won't be able to manage, they will have to introduce exotic materials and designs to cope.
 
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  • #11
How is the orbital frequency of a single atomic electron, and covalent electron, calculated?
 
  • #12
lightarrow said:
The material would become insulating because it's as if the electrons couldn't move freely, however the classical description wouldn't be adequate anylonger and you should use the quantum one.
The simplified theory of conductors and semiconductors uses 'conduction bands' and 'valence bands' to catagorize the energy of electrons in the material. Those are definitely quantum concepts. But the propagation of high frequencies along a wire are derived (I think) from classical E&M ... the external fields can only propagate so far in a conductor because of its super high index of refraction. Is there a quantum derivation of this? The probability that a photon of a given energy (wavelength) will penetrate to a given depth in a wire (modelled as a space charge constrained in a cylindrical potential well)? Perhaps there are tunneling solutions where regions of the conductor can participate in high frequency conduction and 'get around' the classic skin effect.
 
  • #13
diamond reinforce composite wire!
 
  • #14
Umm ... yeah, didn't think of that. Maybe with tachyon beams?
 

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