UCPH – Niels Bohr Institute description

The Niels Bohr Institute in Copenhagen is one of the institutions where foundations of quantum mechanics have been laid down. The Institute is a part of the Faculty of Science of Copenhagen University with strong traditions of research in various fields of theoretical and experimental physics. The Quantum Optics Laboratory is a part of the Danish National Research Foundation Centre for Quantum Optics (QUANTOP). The group works at the forefront of the research in quantum information processing with hybrid systems and quantum interfaces. In 1998, in collaboration with the Caltech team, the first unconditional quantum teleportation has been experimentally demonstrated. Since 1997, the group pioneered a new approach to the quantum interfaces using optically thick atomic ensembles. The group achieved a number of milestones: 2001, the first experimental observation of entanglement generated between two separate material objects – a cornerstone for teleportation and other quantum protocols; 2004, the first quantum memory for continuous variables of light; 2006, realization of the first inter-species quantum teleportation from a light beam onto an atomic ensemble. In 2010-2011 the group demonstrated entanglement-assisted metrology with a spin squeezed state in an atomic clock and entanglement-assisted magnetometry with record sensitivity. Since 2009 the group has actively entered the field of quantum hybrid devices with the results on laser cooling of semiconductor nanomembranes, a proposal for strong electro-opto-mechanical coupling and a proposal for sensing of fields and forces beyond standard quantum limits.

Prof. Eugene Polzik: Head of the lab. Eugene Polzik has earned his Master and PhD degrees in experimental atomic physics from the University of St. Petersburg (Leningrad University) in 1976 and 1980 respectively. From 1990 to 1995, he worked at Caltech where he has performed the first experiments interfacing atoms with nonclassical light. From 1993 to 2002, E. Polzik has been the head of the Quantum Optics Laboratory at the University of Aarhus in Denmark. Since January 2003, his Laboratory moved to the Niels Bohr Institute. Eugene Polzik received the Danish Physical Society Prize in 1999. He is a Fellow of American Physical Society, Fellow of the Optical Society of America and Fellow of the Institute of Physics, UK, member of the Royal Danish Academy of Science. Since 2001 he is Director of the Danish Quantum Optics Centre (QUANTOP).

Prof. Koji Usami: leader of the electro-opto-mechanics group. Koji Usami has earned his Master and PhD degrees in experimental quantum optics from Tokyo Institute of Technology in 2001 and 2004, respectively. From 2005 to 2008, he was a principle investigator at Japan Science and Technology agency where he carried out (with prof. Mikio Kozuma in Tokyo Institute of Technology) experiments with cold atomic ensemble. Since June 2008, he has been at the Niels Bohr Institute and involved in the field of quantum hybrid devices.

Dr. Kjetil Børkje: Postdoctoral fellow in theoretical physics. Børkje got his Master and PhD degrees in theoretical physics from the Norwegian University of Science and Technology in 2003 and 2008, respectively. From 2009 to 2012, he was a postdoctoral fellow at Yale University, working in the group of prof. Steven M. Girvin. At Yale, he focused on quantum optomechanics, and collaborated with the experimental group of prof. Jack Harris. Børkje recently received a postdoctoral fellowship under the Sapere Aude programme – a talent development programme by the Danish Council for Independent Research. He arrived at the Niels Bohr Institute in 2012 and plans to collaborate closely with the experimentalists in the Polzik lab.