Generation of a blue-detuned optical storage ring by a metasurface and its application in optical trapping of cold molecules

A scheme for storage of cold molecules in a hollow optical ring generated by a metasurface grating is proposed.The characteristics and intensity distribution related to the ring’s structural parameters and fabrication error tolerance are theoretically studied. The optical potential and dipole force required for the ring to trap magnesium monofluoride(MgF)molecules are also calculated. The dynamic behavior of MgF molecules in the storage ring is simulated by a Monte Carlo method, which shows that a metasurface-based optical storage ring can be used to trap molecules and is an interesting platform for research into ultracold quantum gases and their quantum-state manipulation.

Cooling and trapping polar molecules in an electrostatic trap

An electrostatic trap for polar molecules is proposed. Loading and trapping of polar molecules can be realized by applying different voltages to the two electrodes of the trap. For ND3 molecular beams centered at -10 m/s, a high loading efficiency of -67% can be obtained, as confirmed by our Monte Carlo simulations. The volume of our trap is as large as ,-3.6 cm3, suitable for study of the adiabatic cooling of trapped molecules. Our simulations indicate that trapped ND3 molecules can be cooled from -23.3 mK to 1.47 mK by reducing the trapping voltages on the electrodes from 50.0 kV to 1.00 kV.

Two-dimensional novel optical lattices with multi-well traps for cold atoms or molecules

We propose some new schemes to constitute two-dimensional （2D） array of multi-well optical dipole traps for cold atoms （or molecules） by using an optical system consisting of a binary 7r-phase grating and a 2D array of rectangle microlens. We calculate the intensity distribution of each optical well in 2D array of multi-well traps and its geometric parameters and so on. The proposed 2D array of multi-well traps can be used to form novel 2D optical lattices with cold atoms （or molecules）, and form various novel optical crystals with cold atoms （or molecules）, or to perform quantum computing and quantum information processing on an atom chip, even to realize an array of all-optical multi-well atomic （or molecular） Bose- Einstein condensates （BECs） on an all-optical integrated atom （or molecule） chip.

Enhanced π-π Interactions Between a C_(60) Fullerene and a Buckle Bend on a Double-Walled Carbon Nanotube

In situ low-voltage aberration corrected transmission electron microscopy(TEM)observations of the dynamic entrapment of a C_(60) molecule in the saddle of a bent double-walled carbon nanotube is presented.The fullerene interaction is non-covalent,suggesting that enhancedπ-πinteractions(van der Waals forces)are responsible.Classical molecular dynamics calculations confirm that the increased interaction area associated with a buckle is sufficient to trap a fullerene.Moreover,they show hopping behavior in agreement with our experimental observations.Our findings further our understanding of carbon nanostructure interactions,which are important in the rapidly developing field of low-voltage aberration corrected TEM and nano-carbon device fabrication.