1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Nanodots vs Quantum nanodots

  1. May 19, 2014 #1
    Basically I'm an organic electrochemist.
    Can any nanosized magnetic materials classified under nanodots ? If so what is the materialistic difference between nanodots & qunatum nanodots?
     
    Last edited by a moderator: May 19, 2014
  2. jcsd
  3. Jun 6, 2014 #2
    Re: Nanodots vs. Quantum nanodots

    The confusion here is understandable. The two materials you describe are roughly the same size. That is, a nanodot or nanosphere may be the same size as a quantum dot. Furthermore, there is a little 'fuzzyness' in the term nano as it is a bit of a buzzword that people co-opt to make their research sound more interesting. This being said, the label 'quantum' refers to materials where quantum effects are perceptible. Allow me to explain this more explicitly:

    Like a baseball reacts to gravitational potential energy, charge carriers (like electrons and holes) react to electrical potential energy. Different materials can have different electrical potential energies, and so one way to make quantum dots is to combine materials with different electrical properties. For example, you can grow GaAs on AlGaAs (Gallium Arsenide on Aluminum Gallium Arsenide... examples of compound semiconductors). These materials have different band gap energies and electrons moving in the conduction band and holes moving in the valence band will 'feel' different potential energies when traveling in GaAs than AlGaAs. If you make the GaAs layer small enough the potential well becomes thinner and classical statistics no longer describe the behavior of the charge carriers accurately and one must use quantum mechanics. This typically occurs when a size dimension reaches a few nanometers. Thus a quantum well may be very wide and long, but only a few nanometers thick (1D of confinement), a quantum wire will be long but not thick or wide (2Ds of confinement), and at last a quantum dot will not be very thick, wide, or long (3Ds of confinement).

    Bottom line: It's a nanodot when it has nanoscale dimensions in three directions. It's a quantum dot when it exhibits quantum properties. A quantum dot can also be a nanodot, a nanodot is not necessarily a quantum dot. See attached files for representations of a quantum well, quantum rods, and quantum dots.
     

    Attached Files:

    • QW.png
      QW.png
      File size:
      21.7 KB
      Views:
      159
    • QRs.png
      QRs.png
      File size:
      34 KB
      Views:
      158
    • QDs.png
      QDs.png
      File size:
      29.3 KB
      Views:
      169
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Nanodots vs Quantum nanodots
Loading...