Scientists develop brain-inspired memory material

July 8, 2016, University of Twente
Two memory states of PZT without ZnO versus multiple states when 25 nanometer of ZnO is applied. Credit: University of Twente

Our brain does not work like a typical computer memory storing just ones and zeroes: thanks to a much larger variation in memory states, it can calculate faster consuming less energy. Scientists of the MESA+ Institute for Nanotechnology of the University of Twente (The Netherlands) now developed a ferro-electric material with a memory function resembling synapses and neurons in the brain, resulting in a multistate memory. They publish their results in this week's Advanced Functional Materials.

The material that could be the basic building block for '-inspired computing' is lead-zirconium-titanate (PZT): a sandwich of materials with several attractive properties. One of them is that it is ferro-electric: you can switch it to a desired state, this state remains stable after the electric field is gone. This is called polarization: it leads to a fast that is non-volatile. Combined with processor chips, a computer could be designed that starts much faster, for example. The UT scientists now added a thin layer of zinc oxide to the PZT, 25 nanometer thickness. They discovered that switching from one state to another not only happens from 'zero' to 'one' vice versa. It is possible to control smaller areas within the crystal: will they be polarized ('flip') or not?

Multi-state

By using variable writing times in those smaller areas, the result is that many states can be stored anywhere between zero and one. This resembles the way synapses and neurons 'weigh' signals in our brain. Multistate memories, coupled to transistors, could drastically improve the speed of pattern recognition, for example: our brain performs this kind of tasks consuming only a fraction of the energy a computer system needs. Looking at the graphs, the writing times seem quite long compared to nowaday's processor speeds, but it is possible to create many memories in parallel. The function of the brain has already been mimicked in software like neurale networks, but in that case conventional digital hardware is still a limitation. The new material is a first step towards electronic hardware with a brain-like . Finding solutions for combining PZT with semiconductors, or even developing new kinds of semiconductors for this, is one of the next steps.

This research has been done within the Inorganic Materials Science group, of UT's MESA+ Institute for Nanotechnology. Within this group, also other attractive properties of PZT have been found, like piezo-electrical behavior: the material can expand using an electric voltage, pressing it can also generate a voltage, in turn.

Explore further: Physicists build "electronic synapses" for neural networks

More information: Anirban Ghosh et al. Multistability in Bistable Ferroelectric Materials toward Adaptive Applications, Advanced Functional Materials (2016). DOI: 10.1002/adfm.201601353

Related Stories

Physicists build "electronic synapses" for neural networks

April 20, 2016

A team of scientists from the Moscow Institute of Physics and Technology (MIPT) have created prototypes of "electronic synapses" based on ultra-thin films of hafnium oxide (HfO2). These prototypes could be used in fundamentally ...

Human brain inspires computer memory

April 28, 2015

How is it possible to create computer memory that is both faster and consumes less energy? Researchers at the Institut d'électronique fondamentale (CNRS/Université Paris-Sud) and CEA-List have unlocked the physical mechanisms ...

Recommended for you

Team invents method to shrink objects to the nanoscale

December 13, 2018

MIT researchers have invented a way to fabricate nanoscale 3-D objects of nearly any shape. They can also pattern the objects with a variety of useful materials, including metals, quantum dots, and DNA.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.