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* Re: "Compare to quantum wires (confined in 2D) and quantum wells (confined in 1D)."... Is that right?? I'd think that wires correspond to 1D, and wells to 0D (a point)... --[[User:Cheese Sandwich|Cheese Sandwich]] 20:40, 19 August 2005 (UTC)
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* You've misread/misunderstoof the sentence. A wire is confined in two dimensions - thus it is a one dimensional structure. A well is confined in one dimension, and it is thus a two dimensional structure. A dot is effectively comfined in all three spatial dimensions, it is a zero dimensional structure.
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* Also: This sentence portion could use some editing: "...as the larger and more red-shifted the Quantum Dots is, the less the quantum properties are." --[[User:Cheese Sandwich|Cheese Sandwich]] 20:43, 19 August 2005 (UTC)
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==What?==
Is there somewhere in the public domain one of those beautiful (and prevalent) pictures of solutions of quantum dots emitting at different wavelengths? If someone could find one, I think it would add to the appeal of this article. If not, perhaps some group would release their copyright for the exposure...
''"Stated simply, quantum dots are semiconductors whose electronic characteristics are closely related to the size and shape of the individual crystal."'' "the" crystal? Which crystal? What electronic properties does the size or shape of "the" crystal impart? Since when are crystals confined to a specific size? There's a cave in Mexico with crystals the size of a bus, could those be quantum dots too? This makes no sense. There's nothing simple about this statement at all. --[[User:MoonLichen|MoonLichen]] ([[User talk:MoonLichen|talk]]) 03:51, 24 February 2011 (UTC)
To give an idea of what I'm talking about, here's a link http://www.research.philips.com/newscenter/pictures/downloads/ldm-nanotech_04-0_h.jpg to an awful enlargement of one of these displays.
[[User:Jonnyapple|Jonnyapple]] 06:28, 2 February 2006 (UTC)
 
== CompanyUse byof this"zero namedimensional" ==
I think that needs to be qualified in some sense, since the dots themselves are obvious not zero dimensional. Perhaps state that "their unique behavior is due (in part) to the relatively small number of atoms they are composed of, and can be explained with models that treat them as zero dimensional". I'm not sure if this proposed statement is actually correct. [[User:Maneesh|Maneesh]] ([[User talk:Maneesh|talk]]) 16:58, 22 April 2011 (UTC)
:Zero-dimensional is merely a reference to the number of directions in which the confined charge carrier can act as a free carrier. In a similar vein, quantum wires might be known as one-dimensional potential wells, and quantum wells as two-dimensional potential wells. I'm currently looking for a good place to put this but can't decide where would be best.
:While the dots/wires/wells are small, they still have dimensions in the nm range - indeed it's hinted at in the introduction and stated explicitly in the production section. -- <small><span style="border:1px solid black;padding:1px;">[[User:Newty23125|<span style="color:white;background:#00007C;font-family:sans serif;">'''&nbsp;Newty&nbsp;'''</span>]]</span></small> 14:04, 23 October 2011 (UTC)
 
== Developments concerning bulk manufacture ==
There is a company, Quantum Dot, that could be treated with an article; "Quantum Dot" currently redirects to "Quantum dot". The website is located at http://www.qdots.com . The company would fall into the [[:Category:Research support companies]]. [[User:Ceyockey|Courtland]] 23:38, 26 November 2005 (UTC)
 
I've added a section in the main article concerning the bulk manufacture of quantum dots. For transparency: I am affiliated with one companies involved, this I've added to my edit in the history section as well. I've tried to strike a tone as neutral as possible in my contribution, including a reference to a press release and an article about current prospects of quantum dots from The Economist. There is as yet no independent news article using the press release as a source. If so, it should replace the original press release as a source. If there are any thoughts, additions or objections please discuss them here in this section. <span style="font-size: smaller;" class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/85.223.101.162|85.223.101.162]] ([[User talk:85.223.101.162|talk]]) 14:51, 7 July 2011 (UTC)</span><!-- Template:UnsignedIP --> <!--Autosigned by SineBot-->
The first company to offer commerical quantum dots was Evident Technologies in 2001. The company is currently located in Troy, New York; website: www.evidenttech.com. Commercial quantum dots include CdSe, PbS, and InGaP quantum dots for life science applications, LEDs, solar cells etc.
 
== now can be dissolved in water ==
== Images ==
 
'The researchers therefore developed an amphiphilic coating, i.e. one with both hydrophobic and hydrophilic properties. The "water hating" side of the polymer material attaches to the surface of the quantum dot. Its exposed hydrophilic side then makes the quantum dot/coating combination soluble in water'
This article needs some illustrations.--[[User:24.241.230.126|24.241.230.126]] 17:29, 31 March 2006 (UTC)
 
http://www.sciencedaily.com/releases/2011/10/111026091008.htm <span style="font-size: smaller;" class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/75.85.14.106|75.85.14.106]] ([[User talk:75.85.14.106|talk]]) 05:53, 29 October 2011 (UTC)</span><!-- Template:Unsigned IP --> <!--Autosigned by SineBot-->
== Good article nomination ==
Sadly, this article failed it's nomination. This is for two main reasons:
# Past the lead (which while [[WP:LEAD|too short]] is understandable), it is unitelligible to a non-specialist (like myself).
# It has no [[WP:CITE|inline citations]] whatsoever.
Regards, --[[user:Celestianpower|Cel]]<font color="green">[[User:Celestianpower/Esperanza|es]]</font>[[User:celestianpower|tianpower]] <sup>[[user talk:Celestianpower|háblame]]</sup> 23:41, 12 April 2006 (UTC)
 
== "experimental proof" vs. controversial ==
== Move/redirect ==
"According to an experimental proof from 2006 (controversial results[33]),"
I think this article should be moved to its more precise scientific name: semiconductor nanocrystal. --[[User:Sunpower|Sunpower]] 14:37, 26 April 2006 (UTC)
How does that sentence make sense? <span style="font-size: smaller;" class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/109.193.165.35|109.193.165.35]] ([[User talk:109.193.165.35|talk]]) 19:53, 31 January 2012 (UTC)</span><!-- Template:Unsigned IP --> <!--Autosigned by SineBot-->
 
== Mistake in Quantum Confinement ==
== Big mistake! ==
 
"since no two nearby electrons can share the exact same energy level according to Pauli exclusion principle"
I am pretty sure this sentence is wrong:
"Quantum dots have quickly found their way into homes in many electronics. The new PlayStation 3 and high-definition DVD players (notably Blu-ray and HD-DVD) to come out all use a blue laser for data reading. The blue laser up until only a few years ago was beginning to be seen as something of an impossibility, until the synthesis of a blue quantum dot laser."
 
I have never heard of this interpretation of Pauli's exclusion principle. If this were true, the term "degeneracy" wouldn't exist. Pauli exclusion only says, that they cannot exist in the very same quantum state. They have to be distinguishable, but not necessarily in energy.
Blu-ray and HD-DVD use gallium nitride (and other nitrogen-base compounds) as materials for quantum wells structures, not quantum dots! Quantum dot lasers are just now trying to find their way into the market, but absolutely not in the short wavelength region (green-blue-violet)! Quantum dots have nothing to do with blue lasers!
 
[[User:Gflaesch|Gflaesch]] ([[User talk:Gflaesch|talk]]) 21:53, 4 February 2012 (UTC)
I would recommend to correct such a sentence, or (better) to completely erase it off.
 
:That whole paragraph is unclear and poorly written. By all means, feel free to [[WP:BOLD|be bold]] and fix it up yourself! If you have any questions about editing I'm happy to try and answer them. [[User:Antony-22|Antony&ndash;'''''22''''']] (<sup>[[User talk:Antony-22|talk]]</sup>⁄<sub>[[Special:Contributions/Antony-22|contribs]]</sub>) 17:49, 5 February 2012 (UTC)
 
== Confinement Energy ==
:Please see [[blue laser]] and the reference in ''Appl. Phys. Lett.'' 86, 073102 (2005).
 
I am pretty sure that the equations for the confinement energy should contain the "'''effective''' electron mass" and the "'''effective''' hole mass" and not the "'''free''' electron mass" and the "hole mass" (while "'''free''' electron mass" is definetly wrong, "hole mass" might not be all that bad since there is no such thing as a '''free''' hole mass and thus in cannot be misinterpreted...) <span style="font-size: smaller;" class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/130.75.157.49|130.75.157.49]] ([[User talk:130.75.157.49|talk]]) 16:50, 3 December 2012 (UTC)</span><!-- Template:Unsigned IP --> <!--Autosigned by SineBot-->
:While the wikipedia entry says today: "Use of [[indium gallium nitride]] as a [[semiconductor material]] suitable for formation of [[quantum heterostructure]]s is proposed. Recently, CdS/ZnS [[quantum dots]] have been used as the gain material in spherical Whispering Gallery Mode lasers; see Applied Physics Letters, 2005, 86:073102.", the reference does not mention the term ''quantum dots''. Someone can give an opinion here? (Please [[Wikipedia:Sign your posts on talk pages|sign your comments]]).
 
== Possible inaccuracy in an illustration title ==
:[[User:Miguel Andrade|Miguel Andrade]] 18:29, 14 July 2006 (UTC)
 
The figure titled ''"Quantum Dots with emission maxima in a 10-nm step are being produced in a kg scale at PlasmaChem GmbH"'' displays QD solutions producing luminescence from violet (470 nm) to orange (610 nm) and thus has an inaccurate title. However, WikiCommons provides correct description as follows ''"Quantum dots with vivid colours stretching from violet to deep red are being currently manufactured at PlasmaChem GmbH at a large scale"''. The manufacturer [http://www.plasmachem.com/shop/en/hydrophobic-alloyed-zncdses-quantum-dot-kit/356--pl-qd-oa-kit.html data sheet] for whole QD kit validates this.
:*A quick note on the use of "quantum dot" vs "nanocrystal." In common usage the two terms are more or less interchangable. However, over the past several years, the nanoscience community has started to make a distinction between what each term refers to. Generally, "quantum dot" refers to small semiconductor islands grown onto a ''substrate'' using [[molecular beam epitaxy]], [[chemical vapor deposition]] or other methods, and hence are fixed in place. In contrast, "nanocrystal" usually refers to ''colloidal'' particles grown in solution, which can then be processed using different methods. The APL article mentioned above uses colloidal CdS/ZnS particles which are then deposited onto substrates to make devices (rather than being grown there directly), hence use of the term "nanocrystal" rather than "quantum dot." --[[User:Aesaunders|Aaron]] 15:31, 7 August 2006 (UTC)
I suppose a new title ''"Quantum Dots with gradually stepping emission from violet to deep red are being produced in a kg scale at PlasmaChem GmbH"'' [[User:Hardman Feidlimid|Hardman Feidlimid]] ([[User talk:Hardman Feidlimid|talk]]) 21:42, 31 October 2013 (UTC)
:Be [[WP:BOLD|bold]]: if you see a mistake like this, click "Edit" and change the text so that it is more accurate. [[User:KDS4444|<span style="font-family:Verdana;"> <span style="color:midnightblue">'''KDS'''</span><span style="color:steelblue">'''4444'''</span></span>]][[User talk:KDS4444|<span style="color:limegreen"><sup>''Talk''</sup></span>]] 11:15, 29 January 2014 (UTC)
 
== Primary sources are overused in this article ==
== Discretization of charge? ==
 
The intro paragraph to this article has at least three references (enclosed in "ref" tags) that point to the primary source of the information they are referencing— this is not the way that citations are supposed to be used in Wikipedia. Citations should point to the place where the statement of fact is published or discussed, not to where the actual information itself is published. For example, when I write in an article "John Smith discovered gravity" and I provide a reference for that fact, the reference should point to a source, normally a third party, stating that John Smith did, in fact, discovered gravity, NOT to John Smith's journal article or the book he wrote in which he explained all about the nature of gravity. References should point to where the statement of fact is ''verified'', not to the place where the fact itself is ''discovered'' nor where it was ''first stated''. I know that may seem confusing, but if you can figure out quantum physics then this can't be much harder to grasp![[User:KDS4444|<span style="font-family:Verdana;"> <span style="color:midnightblue">'''KDS'''</span><span style="color:steelblue">'''4444'''</span></span>]][[User talk:KDS4444|<span style="color:limegreen"><sup>''Talk''</sup></span>]] 11:09, 29 January 2014 (UTC)
I have a problem with the following sentence:
"This confinement leads to (...) and to the quantization of charge in units of the elementary electric charge e"
I agree that the confinement leads to discrete levels and that the charge on the dot is a multiple of the electron charge. To me this sentence sounds however as if charge quantization was a special feature of the quantum dot, which it is not. [[User:Bamse|Bamse]] 01:38, 8 August 2006 (UTC)
 
:This is a good point. In this particular page, the ref to Reed et al, 1988, as the "primary" source of the phrase "quantum dots" is actually superceed by a previous paper on which Mark is the lead author: Reed et al. J. Vac. Sci. Technol. B 4(1), Jan/Feb 1986 pp. 358-360. In fact, without actually having gone through the entire set of literature, I'm more confident that this 1986 paper is more believable as the most-extant use of this phrase given that the phrasing in this paper is: "Here we present data on a completely spatially quantized system (which by extrapolation we define as 'quantum dots') where ...". Indeed, the author explicitly notes that it is "defined" here. On the other hand, the paper cited on the present page is merely a parenthetical note in the abstract: "('quantum dot')". [[User:Tjlafave|TJ LaFave]] ([[User talk:Tjlafave|talk]]) 01:25, 12 February 2014 (UTC)
== One of the "stated" applications ==
:I further agree that citing the most-extant (or "primary" source) is not a sufficient proof of the claim mentioned. I haven't looked closer at the other citations in the introductory paragraph, however, if references 1-3 are of issue, I think the sentence is found in various forms elsewhere on the web, but with different cited sources! E.g. Sigma Aldrich's page on quantum dots. (Apologies if my signature here doesn't work. I don't interact with Wikipedia much -- yet.) [[User:Tjlafave|TJ LaFave]] ([[User talk:Tjlafave|talk]]) 01:25, 12 February 2014 (UTC)
 
== Intro paragraphs needs work, operating principle unclear ==
"Another paper, published in the October 18, 2005 issue of the Journal of the American Chemical Society, reports that Michael Bowers II at Vanderbilt University discovered that certain size crystals of cadmium and selenium emit white light when excited by an ultraviolet laser. This emission appears to be coming from the surface of the crystal, rather than the center. The crystals contain either 33 or 34 pairs of atoms. While they are being pyrolytically synthesized, they preferentially form into just this size; so Bowers can make a batch of such crystals in about an hour. Another student then mixed these quantum dots into ordinary varnish, applied it to a blue LED, and observed that the emission is yellowish-white, like a light bulb. The researchers believe that it will be possible to achieve this emission of white light via electrical stimulation as well as photonic, and hope to demonstrate it soon."
 
The introduction says that quantum dots are nanocrystals made of semiconductors, but doesn't explain what useful features they have. Numerous applications are mentioned, but it remains obscure what the underlying principle is. The first sentence of the third paragraph mentions "emitted light" in passing. Is that the point of quantum dots, that they emits light? Under what conditions will they emit light? Are there other use cases besides emitting light? [[User:AxelBoldt|AxelBoldt]] ([[User talk:AxelBoldt|talk]]) 02:08, 28 November 2014 (UTC)
The quality of writing in this paragraph is a bit lacking, since it reads like someone's laboratory book; is it really relevant which students are involved, or how long it takes to make a batch of crystals? The ideas are ordered haphazardly and some of the sentences are plainly speculative. I suggest this paragraph be rewritten, or just removed.
 
== Proposed merge with [[Artificial atom]] ==
[[User:146.232.75.208|146.232.75.208]] 15:34, 10 August 2006 (UTC)
 
The only known examples of artificial atoms are quantum dots. [[User:Llightex|Llightex]] ([[User talk:Llightex|talk]]) 20:57, 31 March 2015 (UTC)
{{done}}
== Statement about quantum confinement in the sun is unclear and unsupported by references ==
 
In the section "Band cap energy" is a sentence ending:
Seems as though this section was written by the author of the article itself. This article is far from a seminal paper in the field. It should be removed.
 
"which is precisely what happens in the sun, where the quantum confinement effects are completely dominant and the energy levels split up to the degree that the energy spectrum is almost continuous, thus emitting white light."
 
to which I added a "Citation required" note. "in the sun" is not specific enough. Perhaps "in the photosphere of the sun" might be better. If a statement such as this remains in the article, I think it should be more self-explanatory, perhaps have its own section (if it is relevant to quantum dots directly - otherwise it should be somewhere else) and should cite references. A quick Google for sun and "quantum confinement" didn't produce anything which seemed relevant. <small><span class="autosigned">—&nbsp;Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Robin Whittle|Robin Whittle]] ([[User talk:Robin Whittle|talk]] • [[Special:Contributions/Robin Whittle|contribs]]) 10:20, 19 April 2015 (UTC)</span></small><!-- Template:Unsigned --> <!--Autosigned by SineBot-->
==Large literature on quantum dots==
According to Chemical Abstracts today, here are some figures:
73443 papers, patents, whatever refer to quantum dots
52226 have appeared in the past 10 years
2286 of these recent articles are classified as reviews
Conclusions: the literature is so massive we really need to not only stick to secondary sources, and even then the situation is almost impossible.--[[User:Smokefoot|Smokefoot]] ([[User talk:Smokefoot|talk]]) 00:33, 6 June 2016 (UTC)
 
== Spectral image comparison uses a disastrously poor set of index colors ==
 
The colors of the spectral curves really should match the perceived color for each spectrum. <!-- Template:Unsigned IP --><small class="autosigned">—&nbsp;Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/67.100.124.87|67.100.124.87]] ([[User talk:67.100.124.87#top|talk]]) 02:45, 3 May 2017 (UTC)</small> <!--Autosigned by SineBot-->
 
== External links modified ==
 
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== Possible equation error? ==
 
The equation for the confinement energy seems not to agree with the version given in the Brus equation page:
https://en.wikipedia.org/wiki/Brus_equation
The factor in the denominator is 2 in one, 8 in the other, both state that a / r is the radius of the dot. <!-- Template:Unsigned IP --><small class="autosigned">—&nbsp;Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/134.169.19.27|134.169.19.27]] ([[User talk:134.169.19.27#top|talk]]) 08:45, 1 March 2019 (UTC)</small> <!--Autosigned by SineBot-->
 
== QD Periodic Table ==
 
Can someone add more to the the QD Periodic table section? All the images I found didn't explain anything - they pretty much listed a bunch of abbreviations
that were not at all useful. So if someone could clear this up (and list the molecules instead of names that tell you nothing about the chemical itself), that would be very helpful.
 
== Strange statement/link: For a similar biological technology, see Luciferase. ==
 
"For a similar biological technology, see Luciferase." I do not see any similarities between these mechanisms. The reverse link from Luciferase to Quantum dots also seems to be wrong. <!-- Template:Unsigned IP --><small class="autosigned">—&nbsp;Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/141.63.225.199|141.63.225.199]] ([[User talk:141.63.225.199#top|talk]]) 12:37, 15 June 2022 (UTC)</small> <!--Autosigned by SineBot-->
 
:I agree that the link to Luciferase does not belong there and should be removed. If the analogy between the two is made in the literature it could be added (with appropriate citation) further down in the text, but at this prominent place and without explanations it is misplaced and confusing. Likewise the backlink seems unsuitable as luciferase does not only (and not even mostly) have to do with record keeping. [[User:Qcomp|Qcomp]] ([[User talk:Qcomp|talk]]) 10:58, 16 June 2022 (UTC)
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