## Social Networks for Math Majors

This is a small story of Nanotechnology, one of the most advanced and trending topics in physics.

Nanotechnology has become a widely discussed topic today in newspapers, magazines, journals, blogs and even in television ads. It’s very common that some organization announcing ‘yet another’ “nano-conference”. Nanotechnology or nanotech in short, refers to the technology of creating materials, devices and functions using atomically manipulated matter. If you didn’t understand it clearly yet read further lines.
We measure huge distances like billions of trillions kilometers in a term “Light Year”, one light year being the measure of the distance (not the time) traveled by light in one year by it constant traveling with a speed of approximately 300,000 kilometers per second. We measure a certain huge distance in Kilometers or Miles. We measure the length of a tree in meters. We length ourselves in centimeters. Similarly, a rice piece in millimeters and bacterias in micrometers. Micrometers being a millionth part of a meter. If we decrease our counting measures we reach to the size of atom or molecule, measured in nanometer . One nanometer is one-billionth part of a meter. Your hair is almost 30,000 nanometers wide. 🙂 Studying stuffs of size of a nanometer comes to the category of Nano-studies, or as a science– Nanoscience and as a technology Nanotechnology.

# What does this technology mean to us?

We are well developed today. Things are small and easy to use. Chips (not potato chips, but computer chips) are getting smaller. From millimeter length to micrometer length and then to nanometer length. To understand what this mean to us, we need to step back a ‘little’ and look at the technologies in the past.
An era ago, when the man was a hunter and if used tools such as stone-made axes — he had limitations on his jobs like hunting. As times passed away, human learned how to develop sharper tools with metals and more. Stone tools were not enough to kill an animal at the spot, but metal ones were. The human race made several types of tools as part of its evolution and the great works of arts, science and architecture of later years were created with such tools. Today, we manipulate matter such as silicon with optical methods so that transistors and integrated circuits are made, with which we built the era of information technology. The dimension of materials manipulated got systemically reduced with time and [not being the exact data] modern Core i7 chip has above 0.7 billions of transistors in it, each transistor being of size 45 nanometers. So, our stone like tools of meters have now converted into chips of nanometers. It causes an ease in work. This is nano-tech which made possible me to blog via my mobile. Lightened up computers that one can lift them from one place to another.

# Atomic Manipulated Matter! What is that?

All matter is composed of atoms. A button of your keyboard, contains a billion trillion atoms. Even your fingers may have billions of dust-atoms. A coin of 1 Rupee, roughly consists of \$ 10^{21}\$ atoms, all the properties of each atom being the same. Very huge number to count. These kinds of matter, are referred as Atomically manipulated matter.

# Nano-particles

Particles that show the wonders at the nano-scale are known as nanoparticles. Studying nano-tech is Studying nano-particles in other words.

# History

Quantum Corral

Believe it or not, we have already completed first 50 years of nanotechnology. Professor Richard P. Feynman on December 29, 1959, delivered the celebrity talk, “There’s plenty of room at the bottom”, which predicted the future of nanotechnology. He envisioned a new kind of technology by assembling things atom by atom, in today’s terms “Molecular (nano) Technology“. The terminology, nanotechnology itself came into being in 1974, due to prof. Norio Taniguchi. Molecular nanotechnology is a controversial concept attributed to Dr. E. Drexler originating from his famous book, ‘Engines of Creation’ (1986). Feynman talked about writing the entire Encyclopædia Britannica on the tip of a needle; he envisioned that one day the entire information of the world could be contained in an envelope!! He forecasted that little motors could move with blood vessels and do surgeries, as if the surgeon has gone inside a body. Feynman said:

“[The] Principles of physics, as far as I can see, do not speak against the possibility of manoeuvring things atom by atom.”

No talk was talked about so extensively as this one in the history of science, except probably the ‘Candle Light Lectures’ of Faraday.
The predictions of Feynman, to a large extent, have been realised today. Since 90’s, we move atoms one at a time to create structures. A well-defined structure made by Eigler, in 1993 was called a “Quantum Corral”, a confinement or cage or corral was made with atoms. Electrons were confined within this cage. This was made with 48 iron atoms on a copper surface. The methodology to see and place atoms is called scanning tunneling microscopy, discovered by Binning and Rohrer in 1981 (Nobel in 1986). The first example of artificially designed matter at the nano-scale was by Faraday in 1856. He made colloidal hold, which was Ruby red in color. He said,

….they are simply cases of pure gold in a divided state; yet I have come to that conclusion, and believe that the differentially colored fluids and particles are quite analogous…

In order to come to this conclusion that change in the properties of the material happen as a result of a mere change in size and not due to any other chemical change in gold, Faraday conducted a variety of experiments. To make that bold statement at a time when no experimental tools was available to observe particles at this lengths, one has to be prophetic. Time passed and developments by various scientists enriched Nanotechnology.