Nano is small… really small. For an object to exhibit properties of the nano realm it must have at least one dimension (length in a direction) that is in the range of 1-100 nanometers or .000000001 to .0000001 meters.
If it’s hard to think with that many zeros (I know it is for me) just imagine stretching a meter stick from the center to the edge of Earth, a distance of about 6400 kilometers or almost 4000 miles. On this new scale a nano object would range in size from a marble to an exercise ball. An atom on this scale is a little smaller then a BB pellet1.
Most nanotechnologies are divided into three sub sets: quantum dots, nanowires and nanosheets (there are some exceptions)2. Quantum dots are constrained to nano size in all dimensions (directions), making it look like a point from far away. Using the previous image, a quantum dot would lie between the size of a single marble to an exercise ball. A nanowire is constrained in two dimensions, making it look like a line from far away. A nanowire would be akin to a line of marbles or exercise balls. Lastly, a nanosheet is constrained in 1 dimension, making it look like a thin sheet or plane from far away. This is like a table top full of marbles or a building floor full of inflated exercise balls. If we starts to combine some of these nanostructures, we can make larger more complicated structures such as the nano gearing system (Fig. 1).
There’s plenty of room at the bottom, a great nanotechnology lecture from Richard P. Feynman, arguably one of the best physics lecturers and forward thinkers. This I consider a must read for beginning nano enthusiasts. When reading remember that this was given in late 1959, over 50 years ago, before any major advancements in nanotechnology. Feynman was able to look ahead to a future of nanotechnology and see glimpses of what was to come. Much of what he talks about is either being currently worked or has been done.
One example Feynman gives is type setting on the nanoscale. Above is an image done by Don Eigler setting 35 xenon atoms to arrange the spelling of IBM (Fig. 2). Many consider this a historical landmark of nanotechnology, indicating the ability to manipulate each individual atom with great accuracy. IBM continues to push the borders of nanotechnology, for example IBM Research Creates World’s Smallest 3D Map; Brings Low-Cost, Ease of Use to Creation of Nanoscale Objects. I will address this in another post some other day after I set a little more frame work on nanoscience. There are many examples I could bring up about various sections of “There’s plenty of room at the bottom” but I will leave those for another day…
1 Very dependent on the atom in question. This assumes an atom with a atomic number of about 3-18.
2 Some of the exeptions are:
- Super lattices
- Surface materials and etchings