Glass spheres produced by magnetic levitation method

Melting of glass levitated in high magnetic fields has been performed by us ing a hybrid magnet and a CO., laser. A sphere of an optical glass (BK7) ha s been obtained through melting and cooling without any crucible. Raman sca ttering and electron spin resonance (ESR) of the glass sphere showed no spa tial anisotropy with respect to the applied field. Microspheres of binary s odium tellurite glass were also obtained for the first time by an evaporati on-condensation process in high magnetic fields. Thermal convection was sup pressed under a magnetic force of -0.8g. The size of microspheres produced under the magnetic force was about 500 nm at most. This size is one-half th e size of spheres produced without a magnetic field. Raman scattering measu rements on microspheres produced under the magnetic field showed different spectra from those without a magnetic field. The difference is due to a def iciency of sodium ions in the spheres produced without a magnetic field. (C ) 2001 Elsevier Science B.V. All rights reserved.