# Studies

## My very first first-author paper, published in Physical Review B!

The top of the published article

It’s really out! I’ve been working on this article ever since I finished my master’s, and it finally got published. It turned out super well – I am so happy about this! My first first-author article in a scientific journal!

This is basically our reporting on the old hard X-ray measurements that I got to do my master’s thesis on – measurements of the staging superstructure observed in several different samples of single crystal LSCO+O. The measurements were done at several temperatures from down to 5-10 K, up to room temperature – giving us the opportunity to see how the staging appears at different temperatures depending on the doping in the samples. We also reported on the observed cooling rate dependence, which was found to depend on the amount of Sr doping in the samples.

Posted by PJR in Experiments, Publications, Studies, 0 comments

## Aperiodic Crystals school in Antwerp

This last week I participated in the Aperiodic Crystals school held at the University of Antwerp in Belgium. It was a week of lectures and tutorials on modulated crystal structures and quasicrystals, and was basically perfectly catered for what I need for my continued PhD project.

Apart from learning a bunch of useful knowledge about superspace and superstructures, I also got some more knowledge about how to use JANA2006 to solve (in)commensurately modulated structures from single crystal data. Now I just have to figure out how to index the data that I already have…

The week ended up being super busy for me, but there was some time in the evenings to go out with people, finding interesting local beer and food. I was especially happy about finally trying cherry beer (kriek), which I’d never even heard of before. I also got to meet a lot of new awesome people, both fellow participants of the school and lecturers – some of which I’ll meet again soon at the ECM-30 conference in Basel at the end of August.

Posted by PJR in Travel, Workshops, schools, and courses, 0 comments

## Swedish Neutron Scattering Society meeting in Lund

I went to the annual Swedish Neutron Scattering Society meeting held in Lund, Sweden, this year – on Monday May 30th and Tuesday May 31st – to kind of get a feel for what is happening on the other side of the water from here in Copenhagen. I got to listen to a lot of interesting talks – many of them centered around instrument development for ESS and MAX IV – as well as present a poster on some of my more recent work.

On Tuesday we went on a tour to the almost finished MAX IV synchrotron, as well as the ESS – still in the building phase. It was super interesting to see both!

On my trips (I went back and forth by train over Øresund both days) I had some fun taking little video clips, finally resulting in a little video:

Posted by PJR in Conferences, Travel, Workshops, schools, and courses, 0 comments

## Finally done with the master’s degree!

Today I held the master’s thesis defense, at the old auditorium A at the Niels Bohr Institute. My family was there, and a handful of office mates showed up to see it as well. Despite being pretty nervous about it, it all went really well, and even the question session afterwards probably couldn’t have gone better than it did.

You can see my slides on the master’s thesis page, where there are download links for everything related to the thesis (or just look at the slides directly through this link).

A couple of examples of slides from the slideshow used during the defense

All over, I’m really happy with how the project turned out, and I’m looking forward to trying to finish an article for publication of some of the results during December and January.

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## Master’s thesis handed in – preparing for the defense!

I finally managed to hand in my master’s thesis, so I can continue on the remainder of my PhD project! I made a small sub-page on here, just like I did for my bachelor thesis back a few years ago. You can see it here, where you can also see the actual thesis (or just have a look at the thesis directly here).

A look at a couple of the pages from the thesis

I am now preparing for the defense on Monday November 30, and just printed a couple of abstract-posters to hang in the elevator to tell people about it – those can also be seen on the little thesis sub-page I made (or just directly via this link). I’m mostly just looking forward to having this over with.

One day, I’m going to share the LaTeX class that I made for the thesis, so others can use the layout I made, but for now it’s so messy that I don’t think I want to support people on trying to compile the thing…

Part of the little abstract poster that I hung around the office to invite people for the defense

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## Article in Physical Review B!

Top part of the published paper

Astrid put together this awesome paper on the work she’s been doing the last years. I helped with a bunch of the experiments back when I’d just started my PhD, so it is great to get it published too!

As a short description, the article is about the field dependence of the interplanar magnetic correlations in our LSCO-O sample. We found that the applied field enhanced the magnetic moments and increased the interplanar correlations (though only between neighboring planes). Also, these interplanar correlations could apparently also be forced through a fast cooling instead of an applied field.

Posted by PJR in Experiments, Publications, Studies, 0 comments

It feels like I’ve been updating this blog way too rarely the last couple of years – and that’s also the case for the web site as a whole. The last couple of days I have been procrastinating a bit, and had some fun with re-coding parts of the page, and setting up statistics. Turns out, a lot of the notes collections and old hand-ins get a lot of traffic, and it’s interesting for me to look at statistics for this.

Since the last post, I participated in several workshops, courses, experiments and conferences. Worth mentioning was the ICNS conference in Edinburgh, Scotland, two summers ago (July 2013), and a very exciting experiment at IN12 (ILL, France) the same month.

I finished all my teaching responsibilities, after having been a course instructor in the Experimental Physics course three times (although the first time was before I started my PhD) and once in the Neutron Scattering course, plus a couple of smaller things at different summer schools. I’m also almost done with taking courses, since I participated in a large number of workshops during the first part of my studies. I’ve had over a year long hiatus from my studies due to personal issues, and am currently working on getting back, by finishing my master thesis so I can continue on the PhD plan I started back in March 2012. Hopefully this will be over with in the beginning of this summer.

Posted by PJR in Experiments, Studies, Teaching, Website, Workshops, schools, and courses, 0 comments

## My first beamtime at ESRF

We were lucky to get a few days of beamtime on the hard X-ray instrument ID11 on the ESRF in Grenoble, France: from December 1st to 3rd. We measured reflections for several of our LSCO crystals at different temperatures, to get some of the beautiful superstructures in even better resolution that before.

A little look at what the data taking looked like:

I also got to see the mountains surrounding Grenoble from a new direction – I’d never all the way down south by the synchrotron on campus, and had no idea that there was a little roundabout down there either. Either way though, the view was awesome on the days we had sunshine!

A little panorama from ESRF

Posted by PJR in Experiments, Travel, 0 comments

## Another DMC beam time on LSCO+O, and a little PCMO

From November 21 to 28 we had another beam time at the DMC instrument at SINQ, where we measured reciprocal space maps for two of our LSCO+O crystals.

I arrived a couple of days early to align the samples, and had some very late nights because things didn’t want to work – as is seemingly the usual when aligning crystals… If nothing else, I got to entertain myself with how much the sample holders looked like little robots.

The measurements themselves went perfectly, and we had some extra time to put a powder sample of PCMO on the instrument in the end. Hurray for beautiful data to take home!

Posted by PJR in Experiments, Travel, 0 comments

## Introduction to Mantid and Python course

Late last night I landed in a plane from London, after a great week at the Rutherford Appleton Laboratories (RAL) in Oxfordshire, England. I’ve been following a week-long course on the instrument management and data analysis software Mantid, also including some rudimentary introductions to Python. A lot of it was very introductory (which was also the point, I guess), but at least now I have a good feel for how the software can be used both on an instrument and on my own machine for data analysis.

It’s a shame that there is no SXD instrument model in the software yet, so I could work on my time-of-flight data on there – but at least the guys teaching us (the same guys that made the software) were very eager to help people with starting up their own models too. So if I get the time, it seems like I have that option.

I stayed in the same small Bed & Breakfast in East Hendred as last time I was at ISIS (which is also at RAL), although this time I got a room a little outside of town, so I had to walk through their little yard to get to the bus stop. That made for wet shoes from the morning dew, but also some really pretty sunrises!

The little Bed & Breakfast yard made for some spectacular mornings

## A little detour to London on the way home

I spent a small part of Friday in London, before going all the way to Heathrow to catch my plane. I went out to the O2 Arena and then the Emirates Air Line. I took the trip back and forth over the water – with some absolutely beautiful views of the city! I also found time to go to Greenwich Park, where the GMT line is located – and I believe that it is a Unesco World Heritage spot too! The park is huge, but I managed to walk up the hill to the Royal Observatory to enjoy the view. You can basically see all of London from up there (that’s shown in the picture at the top of this post)!

Posted by PJR in Travel, Workshops, schools, and courses, 0 comments

## Structural State of Minerals and its Applications course

PhD course on different software used for X-ray scattering (both powders and single crystals), primarily on minerals – held at the Geocenter at the University of Copenhagen. The course addressed the use of the structural information obtained by modern diffraction methods and computational approaches in mineralogy and materials science and was mainly directed towards PhD students in geosciences and related disciplines. I was hoping to learn more about – in particular – superstructures and how to handle them, since these are found in a lot of mineralogical samples.

We spent a lot of time on basics of crystal structures and diffraction – which was a repeat of what I’ve seen a lot already – but then moved on to looking at behaviour of crystals under varying temperature and pressure, powder diffraction and applications and finally structure interpretation and specific applications in geoscience and material science. We had both lectures and experimental work with an introduction to modern diffractometers using one of the X-ray diffractometers at the department. We also got to test out a range of different crystallographic software in short tutorials.

All in all, I’m not sure if I learned much about superstructures that I didn’t already know, and I definitely did not find the holy grail of how to solve my crystal data – but, if nothing else – it was an interesting course with some new knowledge.

Posted by PJR in Workshops, schools, and courses, 0 comments

## Courses on peer-review, writing techniques, and project management

This last week I have been following a (double) course arranged by the Dark Cosmology Center. They hired in the professional education company Tress&Tress, who arranged two of their courses right after each other – first two days on project management and scheduling, and then three days about writing techniques and the peer-review process in international scientific journals – under the titles “Coping with the challenges of a PhD” and “How to publish in peer-reviewed journals”.

These two people teaching, Dr. Bärbel Tress and Dr. Gunther Tress, were immensely inspiring – and both managed to make the classes interesting and worthwhile. I learned so much about the whole process of writing for scientific journals, as well as about the whole process of going through major projects like a PhD – and I’ll be able to use these new tools directly in my daily life. I can highly recommend to follow these courses if Tress&Tress ever near you!

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## Some extra time on IN12

Since some of our last beamtime on the inelastic neutron instrument IN12 was wasted because of missing and non-prepared equipment, we got an extra piece of beam time, continuing the last experiment we did there in May. We had from June 30th to July 3rd, although the first day was really only to check the alignment on the sample – while the last day was only until the early morning.

## More cool airport visits!

On my way home, I had to switch planes in the Charles de Gaulle airport, which I’ve never done before. What interesting architecture they have! And there were security guards and police on segways, I’ve never seen that before…

Posted by PJR in Experiments, Travel, 0 comments

## Beam time on IN12

From May 11 to 17, I’ve been at the ILL in Grenoble, France, to do an experiment on the triple-axis neutron instrument IN12, where we did inelastic measurements on one of our LCO+O crystals.

We had to spend a whole day on the OrientExpress instrument to co-align our samples, since there were four of them to be used at the same time… It was a horrible puzzle to get them matching up, but we got it done!

The actual measurements on IN12 was done between May 14 and 17, and despite a lot of problems with some of the instrument components not being delivered on time (wasting us a lot of time in the end), we got some great measurements.

One absolutely awesome thing on this trip, was that one of our local contacts at the ILL managed to give us a little tour of the reactor hall. We got to have a look at all of the neutron instruments inside of the inner instrument hall, and we got to stand above the reactor and see the Cherenkov radiation. It was so beautiful. I’m sorry about not having any pictures for here, but their rules are pretty strict about taking photos…

## Some extra photo time in Frankfurt

On the way to France, I had a 4 hour layover between planes in Frankfurt airport, and I took the opportunity to walk around in the huge airport and take pictures of airplanes and fun architecture and decorations.

Posted by PJR in Experiments, Travel, 0 comments

## Working a couple of weeks at the Rutherford Appleton Laboratory

From April 1st to 13th, I’ve been at the Rutherford Appleton Laboratory (RAL) in Oxfordshire, England, to work together with the instrument responsible at the SXD instrument. We’ve been working on my data analysis, but the main thing we did was do extra measurements on two different laboratory X-ray diffractometers on small shavings of the same LSCO+O crystal that we had on SXD. These data will help me get an even better overview of my superstructures, since the X-ray instruments can measure for higher $$q$$ than what we’ve previously been able to.

The two diffractometers were at ISIS (an Oxford Instruments Gemini diffractometer) and the Harwell Research Complex (an Oxford Instruments SuperNova diffractometer), right on the RAL campus, so it was super convenient. We got so much new data – on several different small pieces of the crystal – and at least some of them have really nice resolution. I can definitely use this further!

The Gemini instrument

I stayed at a cute lille Bed & Breakfast in East Hendred, a short ten minute bus drive from campus. The two cozy pubs provided some awesome meals for my dinners, and I felt super welcome there – I’ll be staying there every time I go to ISIS from now on. The guest house at campus is really, really not worth it compared to this place (it was basically the same price, for a way better room, and way better opportunities for dinner)!

## Beautiful London

On the first day, on my way to Oxfordshire, I took a little detour and spent a few hours in London. It’s the first time I’ve been in the city, and I spent my time walking around, mostly along the Thames – visiting the typical tourist spots like Elizabeth Tower, Trafalgar Square, the Tower Bridge, the Gherkin, and the Millenium Bridge at St. Paul’s Cathedral. I had a great time, and I’ll definitely return one day to have a look at some of the less visited places!

## A little side trip to Oxford

I spent one of my days working at the Bed & Breakfast in the morning, and then taking a short trip to Oxford in the afternoon. I visited some of the old colleges and had coffee and pecan pie at one of the (if not the) oldest coffee shops in Europe – Queen’s Lane Coffee House. I used one of those hop-on-hop-off tourist bus things, and they drove us around and explained how things used to work in the old days of the city. It was really interesting!

I stopped at the botanical gardens and had an ice cream while enjoying the beautiful Spring flowers. I also went to see the beautiful Renaissance dining hall at the Christ Church college, where they filmed the Harry Potter Hogwarts dining hall scenes: despite the long line and too many people, it was kind of fun to see.

## Weekend trip to bird-of-prey park and Stonehenge

On Sunday, April 7th, the local contact took me on a trip to a bird-of-prey park and Stonehenge, just to get out and do something, instead of sitting at the Bed & Breakfast working all weekend. It was super cool – and I’m really glad he suggested it!