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Re: "Electric current" does not mean "electron flow"



Taking a look back at Ashcroft and Mermin's Solid State Physics:

The high field Hall coefficient indicates carriers with positive charge for
Be, Mg, In, and Al.

The low field Hall coefficient indicates carriers with negative charge for
Al (there is a graph in my First Edition - p. 15)

The high field Hall coefficient indicates an effective density of carriers a
third of the free electron value.

So Al appears to be predominantly an electron conductor in low magnetic
fields and a hole conductor in high magnetic fields. (pages 299-303)

More complicated than I initially thought!

Larry Woolf; General Atomics; 3550 General Atomics Court, San Diego, CA
92121; Phone:858-455-4475; FAX:858-455-4268; http://www.sci-ed-ga.org

-----Original Message-----
From: William Beaty
Sent: Monday, April 22, 2002 11:57 AM
Subject: Re: "Electric current" does not mean "electron flow"


On Mon, 22 Apr 2002, Larry Woolf wrote:

Bill's comments are in general excellent. But I take issue with one.

Aluminum is an electron conductor, not a hole conductor. It is used to
dope
Si - to make it p-type.

That was from memory, from past PHYS-L discussions, that aluminum
conductivity is partly valance band (holes,) partly electrons. This has
nothing to do with semiconductor doping.

But am I misremembering? Which common metal has both hole and electron
conduction?