Energy Efficient Magnetic Processors Breakthrough

In a major breakthrough for an energy efficient computing, engineers at the Berkeley California University have for the first time magnetic chips that can operate with less fundamental level energy dissipation possibly according to the laws of thermodynamics.
This means that it is possible to achieve dramatic reductions in energy consumption used only a millionth of the energy spent for operation by current computer transistors. This is critical for both mobile devices and their batteries, as for the “cloud” with the huge demand for electricity in the huge data centers.

Magnetic computing is the future

Magnetic computing has emerged as a promising candidate in recent years because the magnetic bits are distinguished by direction, spending as much energy to make them point to the left or to the right.

Energy Efficient Magnetic Processors Breakthrough
The magnetic bit, measuring 90 nanometers, is seen in the form of a bright spot (North) and a dark spot (South). The “H” shows the direction of the magnetic field applied to reverse its value. Photo: Jeongmin Hong and Jeffrey Bokor

“Are two States of the same energy, so don’t waste energy creating a upper and another of low energy,” explains professor Jeffrey Bokor, Coordinator of the team.

Landauer energy limit

In practice, the team has tested and confirmed the limit of Landauer, a term named after Rolf Landauer, who in 1961 found that, on any computer, every single bit operation must spend a minimum amount of energy.

The discovery of Landauer is based on the second law of thermodynamics, which stands that, as any physical system changes, going from a State of higher concentration to a lower concentration becomes more and more cluttered. This loss is called entropy, and exits the system as heat waste.

Landauer has developed a formula to calculate this lower bound of energy required for a computational operation. The result depends on the temperature of the computer, the room temperature, the limit reaches about 3 zeptojoules, or 100th of dissipated energy by a single Atom when it emits a photon of light.

Energy efficiency is possible and highly desirable

Jeffrey Bokor
Jeffrey Bokor received the B.S. degree in electrical engineering from the Massachusetts Institute of Technology in 1975, and the M.S. and Ph.D. degrees in electrical engineering from Stanford University in 1976 and 1980, respectively.

The team used an innovative technique to measure the minuscule amount of dissipation of energy generated by inversion of a nanomagnetic bit. They used a laser to track carefully the direction that the bit was pointing as an external magnetic field that was used to rotate the magnet alignment for “up” and “down” or vice versa.

The data show that are needed only 15 millivolts of energy, equivalent to 3 zeptojoules to reverse a room temperature magnetic bit, effectively demonstrating the Landauer limit.

It’s still a proof of principle, and not actually express ability to buy magnetic processors in stores.

But the team says in his article that “the significance of this result is that computers of today are far from fundamental limit and that further drastic reductions in energy consumption are possible.” said Jeffrey Bokor.