ATOMIC-SCALE MAGNETIC

MEMORY

A Presentation on

INTRODUCTION

Atomic storage (sometimes called atomic memory) is a nanotechnology approach to computer data storage that works with bits and atoms on the individual level. Like other nanotechnologies, nano-storage deals with microscopic material. An atom is so small that there might be ten million billion in a single grain of sand; optimally, atomic storage would store a bit of data in a single atom. Current data storage methods use millions of atoms to store a bit of data. In 1959, the famous physicist Richard Feynman discussed the potential of atomic storage, explaining that every word ever written up to that point could be stored in a .10 millimeter-wide cubic space, if the words were written with atoms.

Older Data Storing Technology

Magnetic Tape

Magnetic recorders have been around in one form or another since the end of the 19th century and were used to make audio recordings long before any of

their other uses. The first form to come into widespread use was the analog tape. In an analog

tape, a strip of plastic coated with a thin magnet coating is wound between two reels. To make a

recording, the motor in the tape recorder unwinds the tape past an electromagnet, called the write

head, at a steady rate.

A recording medium consisting of a thin tape with a coating of a fine magnetic material, used for

recording analogue or digital data. Data is stored in frames across the width of the tape.

The frames are grouped into blocks or records which are separated from other blocks by

gaps.

Floppy Disk

A floppy disk is a thin magnetic-coated disk contained in a flexible or semi-rigid protective jacket. Data is stored in tracks and sectors.

Double sided high density 3.5" disks can hold 1.44 Mb of data.

Optical Disk

An optical disk is impressed with a series of spiral pits in a flat surface. A master disk is burnt by high-intensity laser beams in bit-patterns from which subsequent copies are formed which can be read optically by laser.

Pen Drive

Flash memory combines a number of older technologies, with lower cost, lower power consumption and small size made possible by advances in microprocessor technology. The memory storage was based on earlier EPROM and EEPROM technologies.

Standard-A USB plug – provides a physical interface to the host computer.

USB mass storage controller – a small microcontroller with a small amount of on-chip ROM and RAM.

NAND flash memory chip(s) – stores data (NAND flash is typically also used in digital cameras).

Crystal oscillator – produces the device's main 12 MHz clock signal and controls the device's data output through a phase-locked loop.

What is Atomic-Scale Memory Storage? Using an unconventional form of magnetism called

antiferromagnetism, scientists demonstrated a new, experimental atomic-scale magnet memory that is at least 100 times denser than today’s hard disk drives and solid state memory chips.

IBM researchers have demonstrated a new kind of memory bit that uses only 12 atoms. Until now, it was unknown how many atoms it would take to build a reliable magnetic memory bit, IBM said. Through their research, they found the answer to be 12. The accomplishment is the culmination of nearly 30 years of nanotechnology research, IBM said

How It Works??

With properties similar to those of magnets on a refrigerator, ferromagnets use a magnetic interaction between its constituent atoms that align all their spins – the origin of the atoms’ magnetism – in a single direction. Ferromagnets have worked well for magnetic data storage but a major obstacle for miniaturizing this down to atomic dimensions is the interaction of neighbouring bits with each other. The magnetization of one magnetic bit can strongly affect that of its neighbour as a result of its magnetic field. Harnessing magnetic bits at the atomic scale to hold information or perform useful computing operations requires precise control of the interactions between the bits.

Writing and reading a magnetic byte Figure shows a magnetic byte imaged 5 times in

different magnetic states to store the ASCII code for each letter of the word THINK, a corporate mantra used by IBM since 1914. The team achieved this using 96 iron atoms − one bit was stored by 12 atoms and there are eight bits in each byte.

The Basic Concept

The researchers started with one iron atom and used the tip of scanning tunneling microscope to switch magnetic information in successive atoms. They worked their way up until eventually they succeeded in storing one bit of magnetic information reliably in 12 atoms. The tip of the scanning tunneling microscope was then used to switch the magnetic information in the bits from a zero to a one and back again, allowing researchers to store information.

Smashing Moore’s Law

Which says that the number of transistors on a microchip will

approximately double every two years.

Potential Area of Usage

Super Computers:

Online Database:

Military Database:

Satellites:

ISSUES The technique lends itself to the development of new

magnetic storage and spintronic devices, the IBM researchers wrote in the paper. However, the use of the method for commercial production faces some hurdles: for example, small, energy-thrifty mobile devices cannot support the infrastructure needed for the scanning and tunnelling microscope required.

Another issue is that the test device works at 1 Kelvin, just a degree above absolute zero. Even so, the researchers found that a bit of information can be encoded at room temperature with groups of 150 atoms, which is still much smaller than the million atoms required in contemporary electronics.

ANY QUESTION

Submitted By

ASHISH SINGH

PRN-0900001099

B-TECH SEM VII COMPUTER-I

Under the Guidance of -:

Prof. ASHWANI C. MADANE

BVDU COE , PUNE