RESEARCH AND DEVELOPMENT OF YTTRIUM IRON GARNET SINGLE CRYSTALS

Abstract

Major emphasis was on refining the floating-zone technique to produce single crystal yttrium iron garnets at least 1/2 in. in diameter and 1 in. long with a ferrimagnetic resonance line-width in the X-band frequency range of less than 1 oersted. Yttrium iron garnet (YIG) single crystals 1/4 to 3/8 in. diam with a dielectric constant of about 10 and dissipation factor of 0.002AT 1000 C WERE PRODUCED BY THIS TECHNIQUE. Ferrimagnetic resonance line-widths at X-band of 1.3 oersteds were obtained from polished test spheres. A technique was developed by which several float-zoned specimens were produced with crack-free cross sections. The identity, origin, and means for prevention of a second phase in YIG is discussed. The second phase, a mixture of iron oxide and YIG, was prevented from forming with improved temperature control and slower zoning rates (0.1 in./hr or less). Data are presented from resonance line-width (delta H) measurements at X-band and at C-band. Preliminary results from heat treating exp riments indicate that the delta H of YIG test spheres can be reduc by annealing. A improved technique is described for rapid polishing of YIG spheres. Results of chemical and electrical evaluations of float-zoned YIG are discussed. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jul 02, 1962
Accession Number
AD0282616

Entities

Organizations

  • Texas Instruments

Tags

DTIC Thesaurus Topics

  • C Band
  • Crystals
  • Dielectric Permittivity
  • Dissipation
  • Dissipation Factor
  • Frequency
  • Garnet
  • Iron
  • Iron Oxides
  • Resonance
  • Single Crystals
  • Temperature Control
  • X Band
  • Yttrium
  • Yttrium Iron Garnet

Fields of Study

  • Physics

Readers

  • Materials Science and Engineering.