How I end up using Machine Learning in Optics/Photonics Applications for my PhD
By: Sunny Chugh
Tags: Optics, Photonics, Optical, Electronics, Machine Learning

Like any other PhD researcher, I went to one place where everyone goes when they are not sure what they are looking for and how to find what they are looking for. Yes, you guessed it right — GOOGLE!!

Luckily for me, I already knew that I was looking for some sort of open-source codes/libraries or commercial software to get my hands dirty with photonics modelling applications.

To my surprise what I found…

Commercial softwares - Comsol/Lumerical were expensive for me to buy at that time, and I was not sure to even ask my supervisor to buy as I was not sure which one I will need.

- were expensive for me to buy at that time, and I was not sure to even ask my supervisor to buy as I was not sure which one I will need. Open-source libraries- There are some open-source libraries like Meep, but I think we need to have more. Google, Facebook, Microsoft all adopting this new trend of making their technologies open source for all to learn. But are the big companies in the optical modelling domain ready to go open-source?

There are some open-source libraries like but I think we need to have more. all adopting this new trend of making their technologies open source for all to learn. Fortran- I never bothered to learn about Fortran during my Bachelor’s, in fact, I can say that I chose not to hear or learn about Fortran as it was such an outdated language. The syntax is bad, no in-build plotting library, among other problems. Guess what? People still use it because it is fast and a lot of codes which are still being used were written in Fortran. But still Fortran…

I never bothered to learn about Fortran during my Bachelor’s, in fact, I can say that I chose not to hear or learn about Fortran as it was such an outdated language. The syntax is bad, no in-build plotting library, among other problems. Guess what? People still use it because it is fast and a lot of codes which are still being used were written in Fortran. No optical engineers/scientists community- This hurted me the most. I couldn’t find any blog/website where optical engineer come and share their work and experiences regularly. Till date, I am looking for such websites sharing regular traffic where people talk about photonics (Let me know if you know any such place!).

Machine Learning- the Buzz word…

If you are reading this then there is a good chance that you have heard about today’s technologies buzz words-

Artificial Intelligence, Machine Learning, Deep Learning

Everyone is talking about it. Every new company is using it or wanting to use it. It doesn’t matter whether they need it or not, but they want to use it. Or atleast show that they are up to date with new technologies and making our life easier and better. I guess it is good marketing as well!!

Having heard these buzz words several times from Mark Zuckerberg, Bill Gates, Tim Cook, I thought there is no harm in looking for what exactly is this machine learning?

What the hell is machine learning? Then I understood machine learning is actually statistics plus a lot of other things.

What the hell is machine learning? Credit: https://www.meme-arsenal.com/en/create/meme/1868835

I started with free courses by Prof. Andrew Ng from Stanford and checking for some YouTube videos. I ended up spending more than £1000 doing courses from Udacity and Udemy. For a few months, these courses consumed my every weekend. Literally every weekend. I even had to say no to friends a few times to join for a party. Can you imagine!! I know it was stupid of me. Anyway, it is in the past now…

Machine Learning + Photonics…

First-year into my PhD, I was still looking for a topic which will become my PhD dissertation. Spent months reading various photonics research papers, understanding some initial optical modelling codes with as little help as possible and irritated with almost non-existent online optical scientist community.

And that’s when it clicked me- Shall I try to use Machine Learning for Optical/Photonics Applications?

Yeah, why not!! There is a big online community for machine learning and I had a background in optical engineering. I thought it might work. But remember I was still new in the Machine Learning field and barely scratched the surface to understand and use it efficiently. Then the questions start arising if I had to make it work-

Is it possible or not? Has anybody done it before?

I was not sure which optical application to consider to use Machine Learning with.

to consider to use Machine Learning with. Dataset- There are no open-source datasets available for any optical application. Again no big online optical community.

There are no open-source datasets available for any optical application. Again no big online optical community. Coding help- Is there any initial code available to start with? Or do I have to write everything on my own?

Is there any initial code available to start with? Or do I have to write everything on my own? The Biggest question- Is it really useful to use Machine Learning with optical, or I just wanted to use the buzz word technology in my work?

The idea lost in the wind for almost 6 months…

With the above questions in mind, I gave up on the idea of using Machine Learning in Photonics. I guess this happens to everybody when they look for PhD topics. Every day, they come up with new ideas and then move on. Same happened to me and I got busy in typical optical/photonics application problems.

It was a regular workday and maybe I was getting bored and started checking Google News. I exactly don’t remember. I saw a research paper getting published, which used Machine Leaning in some Photonic Power Splitters problem. And I remember saying this to myself- Oh Shit! You thought about it a few months back and it is possible… and it is not only about my excitement of using buzz word technology with optical applications.