The lowest-loss (≤1 dB/cm) ion-exchanged waveguides in glass doped with PbS quantum dots are presented. Near-field mode profile and refractive index profile using the refracted near-field technique were measured for these waveguides. We demonstrate that the optical properties of this glass unchanged during the ion-exchange process
We perform a lattice study of heavy baryons, containing one (Λb​) or
two b-quarks (Ξb​). Using the quenched approximation we obtain for the
mass of Λb​MΛb​​=5.728±0.144±0.018GeV.
The mass splitting between the Λb​ and the B-meson is found to increase
by about 20\% if the light quark mass is varied from the chiral limit to the
strange quark mass.Comment: 11 pages, Figures obtained upon request from [email protected]