Photonics from afar

Registration fees, travel costs and visas, and time away from home and the lab, are all factors that can make attending scientific meetings in person difficult. Can online conferences provide a solution?

Optics and photonics conferences are seemingly flourishing in number but their attendance can be hindered by financial costs and personal inconveniences. For many years, the idea of harnessing the global connectivity afforded by the Internet to host scientific gatherings in a virtual manner has been considered, but, certainly in photonics, not taken off. Could 2020 be the year that the situation changes? The popularity of a recent online ‘meetup’ in optics suggests that this could be the case.

The inaugural Photonics Online Meetup (POM) was held on 13 January 2020. Hosted by the University of Southern California (USC) that provided the necessary IT resources, the event brought together in a virtual space speakers and attendees from homes, offices and local ‘hubs’ around the world. In total, 66 hubs were registered, including not only a cluster of well-known European and North American institutions but also ones in South Africa, Australia, New Zealand, China, the Philippines, India, Turkey, Argentina, Brazil and Chile (Fig. 1). A total of 500 unique IP addresses connected to the meeting, suggesting that the total number of participants was at least ~1,094 (including 660 in the hubs). However, this may be an underestimate since the co-chair of POM, Andrea Armani of USC, says that not all hubs reported their attendance figures. In total, 103 abstracts were submitted for the nine available contributed oral presentation slots. As a result, a Twitter-based poster session was created to accommodate the demand.

Fig. 1: Photonics Online Meetup hubs.

Map data © 2020 Google

The 66 registered hubs around the world at which attendees gathered to view POM 2020.

Online seminars are not a new idea but POM was much more ambitious. Although just a single day event with a small number of talks, it was the complete conference experience, with coffee breaks, poster presentations, renowned invited speakers and session chairs. Sounds great, but how did it actually work and did everything go smoothly?

The conference had three main sessions, each with a different theme (integrated optics, nanoscale quantum optics, optical materials), session chair (Rachel Grange, Riccardo Sapienza, Mikhail Kats), and an invited speaker. Mercedeh Khajavikhan (previously at the University of Central Florida, now at USC, discussed topological photonics in active platforms; Mete Atature (Cambridge University) covered quantum optics with new materials; and Nader Engheta (University of Pennsylvania) gave a talk on ‘photonic mathematics’, showing that photonic structures can solve equations. Invited talks were 30 minutes each including a few minutes of questions and each session included three contributed talks of 20 minutes duration including 2 minutes of question time. To ask questions one messaged the session chair via the chat client included in the Cisco Webex Event platform.

Interestingly, the virtual poster session actually kicked off several days beforehand, on 9 January. Presenters tweeted a brief summary of their work, along with four pages/slides. These were then all distributed by retweets on the POM Twitter account.

In many ways the meeting went remarkably smoothly, in large part due to the technical support provided by USC. The feedback collected by Nature Photonics has largely been very positive. Was the meeting perfect? No. So what could have been better?

It is generally agreed that the Q&A time after each talk was far too short, with just 2 minutes for contributed talks and not much more for invited talks. Questions being read to the speakers by the co-chairs rather than directly by the participants also diminished the interactive experience and raised concerns regarding the risk of selective filtering.

The online poster session lacked the social aspect of snaking around people-filled rows of poster panels, beverage in hand. Also, perhaps having the posters hosted on a website would have been less distracting than using social media.

Some presenters poorly aimed their webcams, prominently featuring their ceiling as much as themselves, and chairs sometimes had to remind people to mute their microphones, such as during Engheta’s invited talk. The quality of audio varied depending on individual set-up and environment. Not all presenters knew how to share their presentation to the screen immediately, but this is not so different to a conventional conference. There were also minor technical issues for at least one invited presenter.

A disconcerting blank screen, seen before the conference started, was not repeated in the break sessions. Reassuringly the screen instead displayed the upcoming session programme, and a slideshow of images of attendees from POM hubs around the world. Image cames from Cambridge and London (UK), Ottawa (Canada), Milano and Pisa (Italy), Norrköping (Sweden), Paris (France), Stanford, Davis and Baltimore (USA), Tampere (Finland), Sydney (Australia) and Jena (Germany).

In summary, it was a clear demonstration that this type of event can work but is a somewhat different experience to attending a conference in person.

One obvious difference for speakers was the lack of applause after talks. Organizing committee member and session chair Grange (ETH Zurich, Switzerland) remarked on this, but did note that, towards the end of the meeting, multiple hubs were enabled to have an open mic so that clapping could be heard.

Another difference was the lack of direct interaction between participants and the speakers since questions were submitted to, and read out by, the session chair. Engheta, who was an invited speaker, hopes that in the future the person who asks the questions can have an audio/video connection with the speaker, and be viewable by all participants. Nevertheless, he was very enthusiastic about the concept of POM and the potential of reaching a larger audience and told Nature Photonics that he believes that such virtual meetings “are one of the bases for future scientific exchange.”

The successful demonstration of POM does naturally lead to the question, would researchers be willing to give up in-person conferences entirely? Atature, also an invited speaker, told Nature Photonics that although POM proved that organizing a very high-quality online event is possible he feels that the “serendipitous science based on ‘bumping into each other at a conference and talking’ is too valuable to give up in full.” Nevertheless, Atature stated that the online meeting was more efficient than a conventional conference in terms of disseminating research to a large number of people.

“I think there are too many [conventional] conferences as is … considering all the travel time and costs per event, we end up with a highly inefficient use of our time and funds,” Atature stated. “For the primary goal of listening to a team of experts in a particular field, we can do this part efficiently through online events. For the additional goal of meeting colleagues in person to discuss science, fewer conventional conferences can suffice.”

Time zone inconveniences aside, one of the main advantages of an online conference is that those from all Internet-connected regions of the globe may take part, irrespective of travel funds or the need to obtain travel visas. Aneesh Dash (Indian Institute of Science, Bangalore), who spoke at the meeting about graphene oxide/silicon microring resonators with enhanced all-optical resonance tuning, would prefer to spend his time and energy on doing research rather than organizing international travel.

“It feels unethical to enjoy resources [by travelling] that could be better utilized,” Dash emphasized. “Also, sometimes the funds may not be sufficient and I have seen students use their own money due to obligation to attend conferences.”

The next POM event is already in planning. Co-chair Armani says that the biggest scientific issue this time round was choosing the topics; she really wanted to include biophotonics but was out-voted. However, the event is obviously scalable and the debate now is whether to have multiple days, or multiple sessions in parallel. Also, over 50% of the audience were students, so there is a hope to have at least one tutorial session. And, yes, there is a plan to increase the Q&A time, and enable more interactivity by using online platforms such as Google chat rooms.

This online conference was an undeniable success. No, virtual meetings will not entirely replace in-person conferences, nor should they, as Atature explained. But, with their numerous benefits it could be a shame and missed opportunity if online conferences do not displace some conventional conferences, particularly those organized primarily for the purpose of financial gain.

Looking further forwards, the idea of exploiting virtual reality to simulate the full experience of wandering from room-to-room between sessions and ‘bumping’ into former colleagues and new collaborators seems less science fiction and more just a matter of time. Until then, we can all look forward to viewing next year’s POM at a workplace hub or from the comfort of our own homes, regardless of where we are.

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Correspondence to David Pile.

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Pile, D. Photonics from afar. Nat. Photonics 14, 137–138 (2020).

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