Related papers: Back-action-free quantum optomechanics with negati…
We investigate the time evolution of a Bose-Einstein condensate in a periodic optical potential. Using an effective mass formalism, we study the equation of motion for the envelope function modulating the Bloch states of the lattice…
We show that thermalization of the motion of atoms at negative temperature is possible in an optical lattice, for conditions that are feasible in current experiments. We present a method for reversibly inverting the temperature of a trapped…
We investigate a two-dimensional Bose-Einstein condensate that is optically driven via a retro-reflecting mirror, forming a single optical feedback loop. This induces a peculiar type of long-range atomic interaction with highly oscillatory…
We present theoretical as well as experimental results on resonantly enhanced quantum tunneling of Bose-Einstein condensates in optical lattices both in the linear case of single particle dynamics and in the presence of atom-atom…
A generalised method of using feedback to control Bose-Einstein condensates is introduced. The condensates are modelled by the Gross-Pitaevskii equation, so only semiclassical fluctations can be suppressed, and back-action from the…
Light storage in an atomic Bose-Einstein condensate is one of the most practical usage of these coherent atom-optical systems. In order to make them even more practical, it is necessary to enhance our ability to inject multiple pulses into…
For many physical systems which can be approximated by a classical background field plus small (linearized) quantum fluctuations, a fundamental question concerns the correct description of the backreaction of the quantum fluctuations onto…
The dispersive interaction of atoms and a far-detuned light field allows nondestructive imaging of the density oscillations in Bose-Einstein condensates. Starting from a ground state condensate, we investigate how the measurement back…
Negative effective masses can be realised by engineering the dispersion relation in a variety of quantum systems. A recent experiment with spin-orbit coupled Bose-Einstein condensates has shown that a negative effective mass can halt the…
We investigate the cavity optomechanical properties of an antiferromagnetic Bose-Einstein con- densate, where the role of the mechanical element is played by spin-wave excitations. We show how this system can be described by a single rotor…
We study the transport of atoms across a localized Bose-Einstein condensate in a one-dimensional optical lattice. For atoms scattering off the condensate we predict total reflection as well as full transmission for certain parameter values…
Recently, neutral atoms have emerged as a promising platform for quantum computing, offering scalability. In this study, we showcase the realization of atomic qubits in atom-molecular Bose-Einstein condensate, belonging to three distinct…
We demonstrate the control of the dispersion of matter wave packets utilizing periodic potentials. This is analogous to the technique of dispersion management known in photon optics. Matter wave packets are realized by Bose-Einstein…
We report on a generic cooling technique for atoms trapped in optical lattices. It consists in modulating the lattice depth with a proper frequency sweeping. This filtering technique removes the most energetic atoms, and provides with the…
We consider the interaction between a Bose-Einstein condensate and a single-mode quantized light field in the presence of a strong far off-resonant pump laser. The dynamics is characterized by an exponential instability, hence the system…
We investigate the potential for controlling a non-interacting Bose-Einstein condensate loaded into a one-dimensional optical superlattice. Our control strategy combines Bloch oscillations originating from accelerating the lattice and from…
We present a detailed study to show the possibility of approaching the quantum ground-state of a hybrid optomechanical quantum device formed by a Bose-Einstein condensate (BEC) confined inside a high-finesse optical cavity with an…
We study theoretically the dynamics of a a hybrid optomechanical system consisting of a macroscopic mechanical membrane magnetically coupled to a spinor Bose-Einstein condensate via a nanomagnet attached at the membrane center. We…
The paradigm of Bose-Einstein condensation has been associated with zero momentum to which a macroscopic fraction of bosons condense. Here we propose a new quantum state where bosonic alkali-metal atoms condense at non-zero momenta, defying…
Trapped bosonic atoms can be cooled down to temperatures where the atomic cloud experiences Bose-Einstein condensation. Almost all atoms in a dilute gaseous system can be Bose-condensed, which implies that this system is in a coherent…