Rainer Dumke^1,2,12, Zehuang Lu³, John Close⁴, Nick Robins⁴, Antoine Weis⁵, Manas Mukherjee^2,6, Gerhard Birkl⁷, Christoph Hufnagel², Luigi Amico^2,8,9, Malcolm G Boshier¹⁰, Kai Dieckmann², Wenhui Li^2,6 and Thomas C Killian¹¹

1 Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore
2 Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, 117543 Singapore
3 MOE Key Laboratory of Fundamental Quantities Measurement, School of Physics, Huazhong University of Science and Technology, Wuhan 430074, People’s Republic of China
4 Quantum Sensors and Atomlaser Lab, Department of Quantum Science, Australian National University, Canberra 0200, Australia
5 Physics Department, University of Fribourg, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
6 Department of Physics, National University Singapore, Singapore 117542, Singapore
7 Institute of Applied Physics, Technische Universität Darmstadt, Schlossgartenstr. 7, Darmstadt, Germany
8 CNR-MATIS-IMM & Dipartimento di Fisica e Astronomia, Via S. Sofia 64, 95127 Catania, Italy
9 Laboratori Nazionali del Sud, INFN, via S. Sofia 62, 95123 Catania, Italy
10 Physics Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
11 Department of Physics and Astronomy and Rice Center for Quantum Materials, Rice University, MS 61, Houston, TX 77005, USA

J. Opt. 18 (2016) 093001 (28pp)

doi:10.1088/2040-8978/18/9/093001