Manipulation of single atoms and ions is a rapidly developing field. It has shown implications for quantum information processing that directly utilizes quantum mechanics to encode, process and store information onto single ions, single atoms and single photons. In particular, neutral atoms are promising candidates for quantum information processing, as they are believed to be scalable using large optical architecture. The two objectives of this proposal aim at implementing the steps necessary to prove the individually addressed neutral atoms as suitable candidates for quantum information processing. The first objective will demonstrate the deterministic loading of single atoms into the ground state of tight optical tweezers. This will be achieved by producing a Bose-Einstein rubidium atom condensate in a cross dipole trap using diode lasers - a challenging but significant result. We will then superimpose onto the condensate a tightly focused optical tweezer, which we will adiabatically turn on to deterministically trap one atom in the vibrational ground state of the optical tweezer. The second objective is to implement the controlled collision between two trapped atoms. It will be achieved by starting with two atoms trapped in two optical tweezers, where one tweezer is able to move with respect to the other. Bringing the tweezers into contact allows the atoms to interact in the controlled way as they accumulate a phase shift due to their interaction energy. This type of interaction is a first step towards showing a quantum phase gate - one of the few elementary gates required to perform quantum computations. The project will take place in Orsay, in the Quantum Optics Group of the Institut d’Optique, who already developed a strong expertise in trapping single atoms. This work will be part of new long-term collaboration between the Orsay group and the Australian National University.
Source: European commission
