Jonathan Denlinger has amassed significant expertise in x-ray spectroscopy, having been at the ALS since 1993. His experience benefits the many users at the MERLIN beamline and the greater scientific community; this year, he was named an American Physical Society Outstanding Referee for his cumulative work reviewing articles. The recognition is given annually to about 150 referees out of the roughly 71,000 currently active APS referees.
What is your role at the ALS?
I’m a beamline scientist at Beamline 4.0.3, which is a high-resolution, low energy beamline, and I specialize in the ARPES technique—angle-resolved photoemission spectroscopy. Low energy in this case means 10–150 eV, and MERLIN stands for milli-electron volt resolution, which is the ultimate desired goal.
How did you become interested in this work?
My PhD thesis from UC Berkeley was focused on laboratory and synchrotron core-level photoemission spectroscopy that involved automated mapping of the angular dependence of the photoelectrons emitted from a single crystal surface, and my first postdoc at the ALS was in commissioning an endstation to do similar photoemission measurements at Beamline 7.0 at the very start of the ALS in 1993. It was then natural to switch to measuring the angular dependence of the valence bands and the Fermi level in my second postdoc, which also had me regularly visit a Wisconsin synchrotron for traditional ARPES measurements.
I was then hired by the ALS in 1999 to run Beamline 8.0.1, whose primary user program technique was x-ray absorption and x-ray emission (or RIXS). I learned those techniques and was responsible for upgrading that beamline to a new, modern optical layout scheme. I then moved over to the new MERLIN beamline around 2009 in order to escape the solo beamline scientist workload at 8.0 and reconnect to my primary interest in photoelectron spectroscopy.
Congratulations on being named an American Physical Society (APS) Outstanding Referee! What is your process in reviewing papers?
I was not expecting the award at all, because it’s given based on the quality, number, and timeliness of the reports, and I am always late with every review, which then also reduces the number that I review per year. Hence, it must be due to the quality.
Typically, I initially scan the manuscript, download the key citations, and browse them to get a better feel for the context of the result compared to what’s gone on in the past. The first impressions then mull in my mind, and typically multiple weeks pass due to my beamline scientist workload before I can find time to return to the report to dig in deeper. Sometimes at that late date, you find out there’s another layer of articles that you need to read, which can then sort of snowball and make it very stressful after the deadlines I pass. Despite the added stress of even more unpaid work, one of the key benefits of being a referee is that it forces you to stay up-to-date and truly try to understand new research topics, especially the recent topological physics, that I might normally just skim and develop only a superficial understanding of.
Some of my in-depth evaluations come from my beamline scientist experience of helping many groups, and recognition of the various technical artifacts or misinterpretations that can occur in the ARPES measurements. Also, I have an extensive backlog of unpublished data, so commonly, I find myself reviewing data that I have already taken and analyzed, and hence I can give a very detailed, in-depth critique. Sometimes I also include in my reviews an organized summary of literature being cited (to help guide my own thinking), which I think the editors appreciate.
What do you do in your spare time?
My last remaining non-work hobby dates back to my participation in an undergraduate campus film club. I attend a Sunday cinema club in SF every other weekend in the fall and spring to see a film at 10:00 in the morning, following by a half-hour moderated discussion. The screenings are typically soon-to-be-released movies that have been hand-picked from international film festivals. Due to the pre-release rules, the film titles cannot be publicized, which adds a surprise element and fresh perspective to the screening experience.