Another Step Towards Graphene Semiconductors

derGoldstein writes "Ars has an article up about the two latest 'papers demonstrating that, if you change the way the graphene stacks, you obtain a voltage-controlled bandgap ... Between these two papers, a fairly complete understanding of the bandgap behavior in three-layer graphene has been obtained, leaving only the challenge of making the stuff.'"

Comments

The substance that does it all

[neokushan]

Honestly, is there anything Graphene CAN'T do? I'm just waiting for an article to appear that states Graphene may be a cure for Cancer and AIDS rolled into one.
And then I'm fully expecting another article stating that it's more deadly than asbestos.

Re:The substance that does it all

[Chuck Chunder]

Honestly, is there anything Graphene CAN'T do?

Yes.

Fortunately we have lasers for those situations.

2 layer vs 3 layer

[vlm]

I'm having trouble peering thru the journalist filter and not finding any other primary sources.

To a first approximation, the point seems to be that what we used to be able to do with bi-layer two layer graphene, we can now do with tri-layer three layer graphene. Um, OK, thats nice but not "new".

http://arxiv.org/PS_cache/arxiv/pdf/1001/1001.5213v1.pdf

So, aside from purely theoretical "thats interesting, just for the sake of physics", what is the point? More durable, better electrical properties, easier to make (thats hard to believe), stronger, easier to customize and control the above, or what? Someone with access to Nature-Physics to read the actual papers could probably respond?

The article is really poor because it tapdances around the important story which is what I list above.

Re:2 layer vs 3 layer

[John Hasler]

I'm having trouble peering thru the journalist filter and not finding any other primary sources.

I thought it was fairly clear that this demonstrates the existence of a bandgap that cannot be attributed to substrate effects or contaminants.

Re:2 layer vs 3 layer

[gstrickler]

To a first approximation, the point seems to be that what we used to be able to do with bi-layer two layer graphene, we can now do with tri-layer three layer graphene. Um, OK, thats nice but not "new"

No, bi-layer graphene can have a band-gap, but it's not controllable, so it can't be used to make a transistor. Conventionally stacked tri-layer graphene has the same problem. What is new is that by changing the way three graphene layers are stacked allows creating a voltage controlled band-gap, which allows for the creation of a transistor.

Re:A tunable photodetector

[John Hasler]

> Probably just as usefull as any normal phototransistor out there.

Normal phototransistors don't have adjustable bandgaps.

> ...a material with very low electrical and thermic resistence.

And thus also potentially much faster than exisitng photodetectors.