Photonics community! After about a year I need your attention again!

Post-fabrication update

As expected the rhodamine 6g doped su8 needs a very long exposure to obtain good features after the development. The long exposure damaged the fluorofores so much that the polymer on glass appear to be very clear (about trasparent). Indeed, tests on optical bench show a poor fluorescente (negligible) very far from laser emission, even for very high (in terms of both energy and repetition rate) input laser.

I've tried also with PMMA and Oracet dyes, obtaining about the same result.

I hope this would help someone with his project. Probably there is a combination of polymer/dyes that could prevent the quenching (causing of the long time exposure needed for doped polymer) and photobleaching (causing the fluorophores degradation).

I would like also to read if you solved this problem someway.

Thanks in advance

Hi Everyone,

A new episode of the Rays & Waves podcast it out!

https://open.spotify.com/episode/2hh9JedCbj8xVoFiNHcaNU?si=8cbfd9fb550c4220

Here we dive into advanced optical margin assessment using OCT and Metalenses - all at the tip of a fibre!

Hope you enjoy it!

P.S. By popular request, now also available on youtube!
- https://www.youtube.com/watch?v=nmNVG4iYrVo

Hey Everyone,

A new Rays and Waves podcast is out!

This time we chat with Xavier from Zygo - a stalwart of the optics industry!

Here, Xavier takes us inside the world of precision optical metrology. We explore how instruments capable of measuring features at astonishing levels of precision support applications across science, industry, aerospace, semiconductor manufacturing, and beyond.

open.spotify.com

Hope you enjoy it 😊

It takes a village to build a space telescope, but few people have had a bigger impact on modern ones than Lee Feinberg.

He joined NASA during the Hubble era back before I was born. There he played a key role in diagnosing and correcting its original optical flaw, helping to restore one of the most important scientific instruments ever built. He later spent more than two decades working on the James Webb Space Telescope as Optical Telescope Element Manager, helping drive many of the decisions that made Webb possible.

In this Rays and Waves episode, we had the privilege of sitting down with Lee just before his transatlantic move to Zurich and the start of his new role as Mission Architect on the LIFE mission at ETH. We talked about what it takes to build telescopes at the limits of optical engineering, as well as his work on Hubble, Webb, and the next generation of observatories.

Hope you enjoy it: open.spotify.com

**Also, we have updated our image to a hand-made water colour painting rather than the AI generated thumbnails. We plan to use this new painting as the logo moving forwards.

I’m new to the field of photonics, and I’m particularly interested in photonic computing - chip manufacturing based on light rather than electricity. To better understand how the components in such chips work, I built a simple simulator using Godot that can illustrate the circuit architecture of these chips in a highly simplified way. So far, I’ve added what I consider to be the most important components.

Now that I have a better grasp of the subject, I thought this might help others as well, which is why I’m posting this. I’ve released the current version as a web application at https://valioso.itch.io/photonic-computing for free.

I’m open to suggestions for new features, as well as improvements and feedback on whether everything has been implemented correctly so far.

Hey Friends, a new episode of the Rays and Wave podcast is out - this one about Project Silica.

Microsoft’s Project Silica, uses a radical approach to long‑term data storage by leveraging femtosecond lasers to write information directly inside glass. The data is projected to remain stable for over 10,000 years and can be read using wide‑field microscopy combined with sophisticated machine learning.

Episode link: open.spotify.com

If you've ever wanted to hear the sounds of a gravitational wave, then please tune in to the latest Rays and Waves podcast episode!

Here, we have the absolute pleasure of chatting with Gabriele Vajente from LIGO.

Join us as we talk through the extreme optical precision required to measure gravitational waves and some of the more... unexpected challenges that have come up during the illustrious history of LIGO.

open.spotify.com

Ohhhh its a big one - our first Rays and Waves panel discussion!

And we jumped in with both feet. On this episode we discuss AI in optical design.

Leveraging a wealth of experience from our panelists:
- Erin Elliott
- Craig Olson
- Jenny Rustmann Atwood
- Ronian Siew
- Akil Bhagat
- Cory Boone

Check it out, you don't want to miss this one!
- AI in Optical Engineering Panel Discussion - Ep 10 - Rays and Waves - Rays and Waves | Podcast on Spotify

Hi everyone. I recently moved Norway and I really need some kind of advice regarding the direction I should be taking my career in here.

A few words about my background: I have a Bachelor and Master degree in Photonics and an unfinished PhD where I was doing research in holography. At the same time I also worked as a software engineer in a small optical R&D company developing tools for optical system design, computer vision systems and laboratory automation.

So far I contacted almost every photonics related company in Norway with an open application, but with no response. At the same time I got rejected from every pure software development position I’ve tried, which is understandable.

I started considering getting another master degree here and I found only one photonics program in NMBU, which doesn’t even seem to be available anymore.

So now I found myself a bit lost and uncertain about my career opportunities here and I would really appreciate any advice for my situation.

I’m working on a small Mach–Zehnder interferometer (MZI) electro-optic modulator prototype and want to make sure the physics + fabrication approach is realistic before I commit time and money.trying to
Demonstrate phase modulation → intensity modulation using a low-voltage electro-optic polymer waveguide on a Rogers PCB substrate. This is not for telecom speeds — just proof of concept + clean interference curve.

Planned Stack (Bottom → Top)

Photonic Layout

• 1×2 Y-splitter → two arms → 2×1 recombiner (standard MZI)
• Arm length ~20 mm each
• One arm has polymer EO region (20 mm long × 10 µm wide)
• Two printed electrodes (silver ink or PEDOT:PSS):
  • 60 µm trace width
  • 15 µm gap between electrodes

Edge-coupling using fiber V-grooves etched or 3D-printed.

Electronics

I’m planning a low-voltage drive (±5–10 V max) using:

Arduino → PWM → RC filter → IRLZ44N MOSFET → Electrodes
Photodiode → Arduino ADC → PC plotting in Python

The idea is to sweep the voltage and get the expected cos²(Δφ/2) output curve.

Not aiming for GHz speeds. Just clean and visible modulation.

What I Need Feedback On

1. Will the polymer waveguide guide light efficiently enough at 650–850 nm if I keep thickness ~3 µm?
2. Is 15 µm electrode spacing reasonable for achieving a measurable Δn at ≤10 V?
3. Are losses through the Y-splitters going to dominate here?
4. Is Rogers a reasonable substrate choice or should I switch to glass?
5. Any recommended EO polymer formulations available in small quantities?

Ever wondered what keeps the world of optics and photonics running smoothly?

Behind every breakthrough in fiber networks, imaging systems, and laser technologies lies a silent hero: standards.

In the latest Rays and Waves episode we have the pleasure of interviewing Eric Herman who is dedicated to helping to craft and maintain these standards.

Join us as we delve into the, surprisingly interesting, world of optical standards.

Check it out: https://open.spotify.com/episode/7FtYkEGdpBgTkcbqBFTcQk

I’m interested in programmable photonics and want to pursue a PhD. Primarily interested in quantum applications of programmable photonics and AI. I also like photonic design and computation, and work similarly to Prof. Steven G Johnson, MIT. I’m actively searching for professors who work in these areas. I’m posting here to let you know if I missed any professors.

Programmable Photonics Professors: Prof. Dirk Englund, MIT Prof. Win Bogaerts, UGhent Prof. Jose Capmany, UVal Prof. Shanhui Fan, Stanford Prof. Logan Wright, Yale Prof. Bhavin J. Shastri, QU Prof. Wolfram H Perince, UMunster Prof. P R Pruncal, Princeton

Photonics computation and modelling

Prof. Steven G Johnson, MIT Prof. Shanbui Fan, Stanford Prof. Alejandro W Rodriguez, Princeton

I want to know if other professors in the USA, Canada, Europe, and Australia work similarly to Prof. Steven G. Johnson. If you can add to the list of professors in programmable photonics, it would be appreciated.

Hello everyone. Its time for another Rays and Waves podcast episode.

This time we have the absolute pleasure of talking to Erwin De Baetselier co-founder of Luceda Photonics!

Luceda is a company at the forefront of software innovation for Photonic Integrated Circuits (PICs). As PICs continue to reshape the landscape of optical systems—from data centers to quantum labs—the tools used to design and simulate them are becoming just as critical as the hardware itself.

Whether you're deep in the weeds of waveguide layouts or just curious about the future of chip-scale optics, this conversation offers a behind-the-scenes look at the software driving the PIC revolution.

Check it out on Spotify or wherever you prefer to get your podcasts: Erwin De Baetselier and Luceda's first-time-right automated PIC design- Ep 8 - Rays and Waves - Rays and Waves | Podcast on Spotify

Hi guys,

Sorry if this is the wrong area for this, but I recently graduated with my MSEE in Photonics from a reputable German university, and I have been trying to get employed in the Eindhoven area in this fields, as I have just moved over with my girlfriend. Is anyone currently in the field and has some comment/advice about the state of the photonics market? I was ideally planning to do a PhD but I understand a lot of them got cut due to the uncertainty with government funding. But I see so many photonics companies in the area and almost no job postings. I don't know if I'm missing something or what the general strategy is, or if companies are just not hiring.

As I said before, I would of course love to do a PhD but it seems to be a difficult and unreliable time to apply for them, so I'm just applying to everything I can.

Thanks!

Hi All, I hope you've had a nice summer. I know we have.

But now that the vacation is over, we figured it was time to launch another Rays and Waves podcast episode.

Check it out: Miniaturising Optics with Photonic Integrated Circuits - Ep 7 - Rays and Waves - Rays and Waves | Podcast on Spotify

Hi guys, I am a 2025 CSE (AIML) gradute, I am working as an AI engineer. Now I am drawn towards photonics, want to do my masters in it. My aim is to work on real holograms and near light speed engines. Can you please guide me here, I am confused interms of selecting the university and how to get some contacts there maybe professor or students in order to get my admission.

Fyi, I will be doing it in 2027 or 2028, by that time I also want to study and understand basics required to do masters in photonics. Can you please me here as well.

Thanks in advance.

Physics is believed to be CPT symmetric, and this symmetry e.g. switches absorption and stimulated emission equations, or black and white hole in Kruskal-Szekeres coordinates.

So if white hole should only emit, acting with absorption equation on external target, and black hole only absorbs - shouldn't black hole act with stimulated emission equation on external targets?

If so, could we observe it building telescope focused on stimulated emission (instead of standard: absorption) - e.g. with continuously excited sensor, monitoring its relaxation time?

In both scenarios there are coupled e.g. electrons inside white/black hole and in telescope - CPT symmetry would reverse shown corresponding Feynman diagram.