CsYb Project: News
Stefan attends YAO 2014, ICFO, Barcelona
April 2014

Stefan recently represented the CsYb team at the annual Young Atomic Opticians (YAO) conference at the Institute of Photonic Sciences (ICFO) in Barcelona. At the conference Stefan presented his talk entitled "A dual-sepecies MOT of Cs and Yb", in which he discussed the technical challenges involved in creating a green Yb MOT loaded directly from a Zeeman slower. The talk also incorporated a detailed outlook on what lies ahead for the experiment, including the search for the first alkali-alkali earth type Fesbach resonances. Leonardo Fallani's talk on ultracold Yb trapped in optical lattices was a particular highlight of the conference.

Dual-species magneto-optical trap of Caesium and Ytterbium
December 2013

On the 4th December 2013 a dual-species MOT of Cs and 174Yb was formed. This is the first observation of such a system worldwide. The Cs was first loaded from our Zeeman slower into our MOT region, then the Zeeman slower coils currents were switched allowing us to load an Yb MOT whilst retaining the Cs. The trapped species are spatially separated due to pushing by their respective MOT beams.

First observation of Ytterbium in a magneto-optical trap
December 2013

On the 2nd December 2013 an Ytterbium MOT was first observed in the science chamber of our experimental apparatus. This is the first Yb MOT on the green 556nm intercombination line produced in the UK. The first MOT we produced trapped the abundant 174Yb isotope, and we have subsequently trapped 172Yb and 176Yb as well. The MOT is loaded from our dual species Zeeman slower on the 399nm singlet transition into a trapping region formed by retro-reflected 556nm beams.

Stefan attends Cold and Ultracold Molecules Workshop, Granada, Spain
November 2013

Stefan recently attended the Cold and Ultracold Molecules Worshop in Granada, Spain. The conference spanned three days in the Escuela de Estudios Arabes where various topics were discussed ranging from novel techniques of directly cooling molecules to Efimov states. Our latest poster, entitled "Towards a quantum gas of polar CsYb molecules", was presented by Stefan during the Tuesday afternoon poster session. Stefan's highlights of the week were a talk on new physics near the atomic asymptote in diatomic Strontium and the Spanish cuisine!

Steve and Ruben visit Düsseldorf
September 2013

Steve and Ruben recently visited the YbRb group in Düsseldorf to ask some questions about their Yb lasers and spectroscopy sources. The visit was very helpful in that it let us know that we are on the right track with our own equipment. Further visits will take place in the future as part of a Royal Society exchange programme.

Evidence of the Yb beam seen in the main vacuum chamber
August 2013

The 399nm laser set up has been moved into the main lab and the first Yb spectrum obtained from the atomic beam in the vacuum system. The beam profile was measured at various points along the system and the full width at half maximum of the beam is approximately 5mm, which agrees with the measurements taken with the Cs beam. The graph shows the spectrum for Yb including all of the more abundant isotopes.

Ruben moves to Durham
June 2013

Ruben and the lasers for Yb moved up to Durham from Imperial. The lasers will be set up again and characterised to make sure they survived the transfer!

Cs MOT achieved in science chamber
February 2013

A Caesium MOT was obtained in the main science chamber with approximately 108 atoms. Additional characterisation of the Zeeman slower and optimisation of the MOT will follow before we implement Degenerate Raman Sideband Cooling to cool the Cs atoms further.

Vacuum system assembled
December 2012

The vacuum system for the CsYb experiment is now complete. The final connection between the oven and the science chamber was made earlier this month after extensive calibration of the Cs beam produced by our source. Following a final bakeout into the ion pumps over the festive period we will be ready to begin testing our Caesium setup. Characterising the Zeeman slower will be the first priority, closely followed by an attempt to form our first Caesium MOT in the new science chamber. The new year will also see Ruben arrive, bringing with him the Yb laser setup developed by our collaborators at Imperial College London.

Zeeman slower wound and tested
October 2012

The dual-species Zeeman slower has been wound and the field along the length of the device has been calibrated. The graph to the right shows the measured fields for our designed Yb (Blue) and Cs (red) currents compared to the ideal fields used to design the coil arrangement. Also shown are the residuals from the ideal field, which are within 3 G along the active part of the slower. As a final check we have seen that the design parameter, η, along the slower matches the values of 0.125 (Yb) and 0.5 (Cs) used when the slower was designed.

Cs MOT achieved
September 2012

The laser system for Cs has been tested by creating a MOT of Cs atoms in an old, existing pyramid MOT chamber. Approximately 107 atoms were trapped in the MOT, which can be seen as the middle cloud on the picture to the right (the other clouds are merely reflections from the pyramid mirrors). The MOT demonstarted the stability and reliability of our lasers.

Optics for Cs complete
July 2012

The lasers and accompanying optics have been set up in Lab 64 and are complete. Some of the light from the cooling laser has been injected into a tapered amplifier to provide enough light for the MOT, Zeeman slower and Degenerate Raman Sideband Cooling (DRSC) beams. The repump laser will provide light for the MOT and Zeeman slower repump beams as well as the polariser beam required for DRSC.

The next step is to couple the separate beams into optical fibres in order to deliver the light to the main experimental table.

Annual MMQA meeting
December 2011

The annual MMQA meeting was held in Durham this year, with our collaborators from Imperial College London coming up to listen to progress report talks given by all of the postdocs involved in the grant. For the CsYb experiment, Steve gave a talk entitled "Towards a quantum array of CsYb molecules"; this, along with all of the other talks given at the meeting will be made available on the MMQA website. A poster was also presented at the meeting.

This was a good opportunity for the whole CsYb team, both Imperial and Durham halves, to meet to discuss progress on the vacuum system design, Zeeman slowers and 399nm lasers.

Visit to Innsbruck, Austria
November 2011
Kirsteen and Michael went to visit the ultracold atom experiments at the University of Innsbruck, as well as those at the Institute for Quantum Optics and Quantum Information. Whilst there, Kirsteen gathered information on how to design Zeeman slowers and vacuum systems, similar to those being planned for the CsYb experiment, whilst Michael learned some technical details about the STIRAP process and about working with Cs at high magnetic fields.
Visit to National Tsing Hua University, Taiwan
August 2011

Steve and Kirsteen recently visited the National Tsing Hua University in Hsinchu, Taiwan. As part of an exchange scheme run by the Royal Society, the purpose was to discover what research is being undertaken there, as well as taking the opportunity to learn about, and get some hands on experience with, a frequency comb. They also visited the national standards laboratory for Taiwan, which is housed in the Industrial Technology Research Institute, to see their frequency comb facilities.

Whilst in Taiwan Steve gave a talk, entitled "Introduction to bright matter wave solitons: Formation, dynamics and open questions" to the AMO summer school in Tainan.

Updated by Kirsteen L. Butler, August 2011