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Re: [Phys-l] Transparency

> How does diamond fit into this 'insulator not= large gap

It is the canonical example of a large-gap semiconductor.

A rather large temperature would be required for diamond to carry an 'injected' charge wouldn't it?


That's just the point. Temperature has got nothing to do with
the motion of /injected/ charge. Once an electron has been injected
into the conduction band, it moves as freely as it would move
through a vacuum.

Temperature has everything to do with the spontaneous production
of non-injected charge, but nothing to do with /injected/ charge.

I am curious: how would one typically inject charge into diamond? Could you just deposit a metal electrode on it and have it work efficiently?

If I take a chunk of copper, for example, and connect a multimeter to it to measure its resistance, the mere placement of the probe by hand is enough to inject plenty of charge to form a measurable current and make the determination. My intuition might tell me that I would measure an analogous diamond chunk as having very high resistance, and hence would assume it to have insulating properties. But I wouldn't know if my issue was the probe (that is, a poor experiment). Your point is well taken though - high resistance is not charge immobility, although I'm not sure where the line is crossed.

I don't know enough about diamond to make good guesses. For example, I might expect its work function to be similar to C, which is comparable to that of other metallic elements.

Stefan Jeglinski