Scientists Find Flaw in Quantum Dot Construction

ThePolkapunk writes "Scientists have been having problems in predicting the behavior of Quantum Dots, which are considered to be the most likely material to be used to build nanocomputers. Physorg is reporting that physicists at Ohio University believe they've found the problem, and it's with a flaw in the construction of quantum dots. If their theory pans out, "It's one more step towards the holy grail of finding a better quantum bit, which hopefully will lead to a quantum computer."" We first mentioned this about six years ago.

Comments

I guess this seems as good a place as anywhere

[mcc]

to ask this...

The guy who wrote "the wellstone" is convinced that quantum dots can also be used to create programmable matter, something he came up with in one of his science fiction books.

I am just curious. Is this (programmable matter via quantum wells/dots) something that actual work is being done on anywhere, or that actual signs of progress can be seen in, or that Mr. McCarthy has the actual capacity to encourage actual science work to be done on? Or is this just a lone science fiction author running around trying to convince people to take him seriously?

Re:Do we need quantum bits?

[necama]

Quantum key distribution is cryptographically equivalent to one time pads, but better -- it solves the key distribution problem; you don't need to take all the one-time pads with you when you leave.

Go watch a fleet prepare for setting to sea, and you'll see them loading one time pads onto the ship by forklift.

Quantum dots can be a lot of things

[UnHolier than ever]

I think it's important to point out that what these people are doinmg is not the whole story about quantum dots. They use a particular technique, and they found a way to improve it, but other people are using completely different techniques that have different advantages and disadvantages. Using "Scientists Find Flaw in Quantum Dot Construction" as a title is very misleading; it's like if an amelioration to firefox was reported as "Scientists find flaw in networking that could fix the internet".

Re:Do we need quantum bits?

[lgw]

>Shor's algorithm is in P, not NP
Yikes. First of all, P is contained in NP. In other words, it's impossible for something to be in P but not in NP.
Secondly, Shor's algorithm is NOT in P. P is the set of languages decided in polynomial time by a deterministic Turing machine. Shor's algorithm runs in polynomial time, but it is NOT in P.


This is an important point for math geeks. The reason quantum computers solve these problems more quickly is that they are not deterministic. They can therefore solve Non-deterministic Polynomial problems in polynomial time. Assuming, of course, that it's actually possible to build a quantum computer.