Moore’s Law: Beating The Noise Problem

If it works in biological systems, why couldn’t stochastic resonance improve the performance of memory chips?

We’re often told that Moore’s Law promises an exponential increase
in the density of transistors on a chip, but we hear much less about
the challenges this generates. One of these is the noise problem.

As transistors become smaller and their power requirements drop,
noise becomes an increasingly difficult to combat. The result is that
chipmakers are being forced to accept a higher error rate in
computations.

But in certain nonlinear systems, particularly biological ones,
researchers have long known that instead of swamping signals, noise
can play the opposite role, helping to enhance them. The phenomenon
is known as stochastic resonance and it has been observed in systems
such as neurons and even exploited to improve the perception of
certain signals.

It’s relatively straightforward to demonstrate the phenomenon
using a ring of identical oscillators driven by a harmonic signal.
The harmonic signal generates a travelling wave around the ring but
this quickly dissipates after the signal is switched off. Add noise
to the system, however, and the travelling wave survives for much
longer.

Could there be a way of exploiting stochastic resonance to make
computer memory, ask a team from the Instituto Tecnologico de Buenos
Aires in Argentina. Their idea is to build a resonator consisting of
just two oscillators. They show that such a resonator is able to
store a single bit of information in a noisy environment, even after
the driving frequency is switched off. They have even built a device
that stores a single bit of data in this way.

What isn’t clear, however, is exactly what kind of improvement
would be possible on the nanoscale at which a real memory element
would have to work. That’s obviously something for the future.

For now, these guys have a clever idea that could have important
implications for data storage in future.

Ref: arxiv.org/abs/0911.0878: One-Bit Stochastic Resonance Storage Device