Subject: Summary: Calculations on quantum dots?

From: Dermot Brougham <[email-masked]>
Date: Wed, 13 Sep 2000 13:07:47 +0100

My original question was:
>Have people calculated the electronic states of the interacting 
>electrons in a quantum dot from first principles. Or, if there have been 
>no ab initio calculations, other more "approximate" methods would be 
>interesting. A citation search throws up a lot of stuff, which as an 
>outsider I cannot prune down.
>So my question is; what are the key papers and who are the key people, 
>or has the area been reviewed?  

I summarize the replies below:

Niri Govind and Michael Nolan suggested Alex Zunger.
Zunger is at the nation renewable energy lab in Colorado. He has
published a lot of work using pseudopotentials on Quantum Dots.

Susan Atlas suggested Das Sarma who I think is in Bangalore, India.
Sarma has published a lot of work involvng spectroscopy and
calculations.

Guido Raos suggested J. R. Chelikowsky (University of Minnesota) and
coworkers who have done first principle DFT calculations of the 
electronic states of large Si clusters (several hundred atoms). 
eg S. Ogut, J.R. Chelikowsky, and S.G. Louie: "Quantum Confinement and 
Optical Gaps in Si Nanocrystals," Phys. Rev. Lett. 79, 1770 (1997).

These were helpful and interesting contributions, but they didn't help
me cut down the search that much. Probably the most useful respense was 
>from Dage Sundholm, 
I will quote Dage directly:

>We use the finite mass approximation and solve the Schrödinger equation
>for electrons and holes coonfined in a QD the size (radius) of which is 
>about 40 nm. We have studied QDs containing up to 10 carrier pairs
>using full configuration interaction and for the larger dots truncated 
>configuration interaction such as the all singles, doubles, triples and
>quadruples (SDTQ) CI method. Our paper is enclosed in pdf format.
>To my knowledge this is the most accurate method applied on this kind of
>QDs.  Hawrylak has also done some calculations, but not very extensive 
>correlation calculations. 
>See: L. Jacak, P. Hawrylak, and A. Wojs,
>     Quantum Dots (Springer, Berlin, 1998).
>For smaller dots (less than 5 nm) the molecular approach has to be used.
>In this context I can mention Zunger and coworkers in Boulder Colorado.
>An other family of quantum dots are large QDs containing only electrons.
>This kind of QDs has been studied by several groups, since the same 
>methods as used in atomic and molecular physics or quantum chemistry 
>can be applied. The only difference is that the nuclear attraction potential 
>is replaced by a confinement potential. For example in Finland 
>at least two different groups (at University of Oulu and at the 
>Technical University of Helsinki) have studied this kind of QDs 
>at ab initio level.
>[email-masked] 

Dage's paper was:
Full configuration interaction calculations of electron-hole correlation
effects in strain-induced quantum dots     PHYS REV B 61: (11) 7652-7655
MAR 15 2000 
I am sure he would make this available to anybody else who is
interested, I didn't want to do this with somebody elses work!

	Many thanks again to all who replied.
			Dermot

Dr. Dermot Brougham,
School of Chemical Sciences,
Dublin City University,
Dublin 9,
Ireland.

[email-masked]