Alice Selby, who is currently working on a PhD at NUI Galway. Image: Aengus McMahon
Alice Selby is working on her PhD at NUI Galway to develop memristors to work more like the human brain, making future devices incredibly powerful.
One of Ireland’s most recent scientist arrivals is physicist Alice Selby, who secured a first in her master’s in physics and nanotechnology from the University of Hull in 2017.
Her master’s project looked at the planar memory resistors – referred to as memristors – and titanium oxide nanogap devices. This is a fairly new research area as the first memristor was fabricated only a decade ago by HP, and even now scientists are unsure how they fully work.
Since graduating, Selby has travelled to Ireland to work on her PhD in neuromorphic nanowire networks under Dr Jessamyn Fairfield at NUI Galway.
What inspired you to become a researcher?
I specialised early on as I was fascinated in spin mechanics and possible applications. After being allowed to teach my class about quarks at 14, I read very deeply into the subject thanks to many encouraging teachers who pushed for students to do more, such as allowing exams to be taken early.
I enjoyed teaching and helping others, and I chose the field I have because of the ability to use my love of maths and physics for helping a larger number of people.
Can you tell us about the research you’re currently working on?
I joined Jessamyn Fairfield’s lab as the first student to work day-to-day on fabrication of nanowire devices.
Fairfield has done studies on memristive nanowire networks, a paper I read myself during my master’s degree. These networks would often choose the shortest path and were observed to respond to neuron spike patterns in a similar fashion to the brain.
This latest study is more about how these devices work, the varying structures they can have and their neuromorphic properties. This includes how the devices respond to electrical pulses and the ‘memory’ associated with that.
We are working on developing more of these devices with various materials to characterise their properties, finding the best materials for biocompatibility.
In your opinion, why is your research important?
The research of memristors is often based upon crossbar arrays and their ability to combine processing and memory into one area. They are smart, small-scale devices that can be packed tightly and used to advance computer power.
These devices can also act as artificial neurons. They respond to the same stimuli and will be able to interact with the brain, acting like a bridge over deteriorating paths.
We are looking into the advancement of devices for helping those with neural degenerative diseases such as Alzheimer’s, affecting an estimated 50m people worldwide. The same technology can be used in advancing prosthetic limbs, where there is almost one amputation conducted every 30 seconds.
With these statistics, it is obvious that this research is important. As we look more into how the brain works, it may even be adjusted and utilised in other neuron types.
What commercial applications do you foresee for your research?
In Galway, there are a number of medical device companies, so moving for a collaboration in this area once there are positive preliminary results is likely.
On top of the medical implications, our reliance on new and better devices every day requires us to utilise some other form of memory before the end of Moore’s Law as we are reach the scaling limits of current complementary metal-oxide-semiconductor technology.
There is a gap in the market and, by replicating the high-density memory and self-healing nature of the brain, we can fill this.
What are some of the biggest challenges you face as a researcher in your field?
It is difficult for me as a physicist to go back and relearn the biology and chemical potential of these devices.
Choosing materials that don’t just have the best on/off ratios and retention is important. You need to compromise with the matching of material properties as well as determining their toxicity and spiking potentials.
As in any new field, the research area is niche, so finding collaborations that benefit all can be more time-consuming.
What are some of the areas of research you’d like to see tackled in the years ahead?
There are so many areas that already have funding and are so easy to imagine for the years ahead. Better artificial intelligence, algorithms without bias and medical devices that allow patients to be more independent are all fascinating to me.
But what I most want to see for the next couple of years are studies on the disparity in STEM fields and new ways of collaborating with the public, future scientists and those we have lost down the ‘leaky pipeline’. Listening to these ideas can only later bring about greater advancements later.
