Low-loss UV to mid IR optical tellurium oxide glass and fiber for linear, non-linear and active devices

An oxide glass composition, comprising:

• a glass network former of Tellurium (IV) oxide TeO2 of 65 to 90 mole percent, said Tellurium (IV) oxide having an absorption feature with an inherent absorption wavelength corresponding to its phonon energy peak;
• a glass intermediate of Lanthanum (III) oxide La2O3 of 5 to 15 mole percent, said Lanthanum (III) oxide having an absorption feature with an inherent absorption wavelength longer than that of Tellurium (IV) oxide;
• and a glass modifier MO of 0.2 to 35 mole percent where M is selected from Mg and Zn, said modifier having an absorption feature with an inherent absorption wavelength longer than that of Tellurium (IV) oxide;
• non-zero amount of fluoride up to 0.5 mole percent, said fluoride having an absorption feature with an inherent absorption wavelength longer than that of Tellurium (IV) oxide;
• and wherein said oxide glass composition is substantially free comprising less than 0.1 mole percent of each of the following,
• Sodium Oxide Na2O;
• Hydroxide OH—;
• and
• any other passive glass constituent having an absorption feature with an inherent absorption wavelength shorter than that of Tellurium (IV) oxide;
• wherein said oxide glass exhibits an optical loss of less than 2 dB/m over the entire spectral range from 0.6 microns to 4.5 microns and less than 0.5 dB over a spectral range of 2 microns to 4 microns;
• wherein said oxide glass exhibits a tensile strength of at least 50 KPSI;
• and wherein said oxide glass exhibits a ΔT=Tx−Tg of at least 100 C. where Tx is the crystallization temperature of the glass and Tg is the glass transition temperature.

A method for forming an oxide glass, comprising:

• providing a mixture of powdered oxides comprising, a glass network former of Tellurium (IV) oxide TeO2 of 65 to 90 mole percent, said Tellurium (IV) oxide having an absorption feature with an inherent absorption wavelength corresponding to its phonon energy peak;
• a glass intermediate of Lanthanum (III) oxide La2O3 of 0.2 to 15 mole percent, said Lanthanum (III) oxide having an absorption feature with an inherent absorption wavelength longer than that of Tellurium (IV) oxide;
• and a glass modifier MO of 0.2 to 35 mole percent where M is selected from Mg, Ca, Sr, Ba, Zn, Pb and Cd, said modifier having an absorption feature with an inherent absorption wavelength longer than that of Tellurium (IV) oxide;
• and a halide of 0.2 to 7 mole percent, any said halide having an absorption feature with an inherent absorption wavelength longer than that of Tellurium (IV) oxide, said mixture comprising a non-zero amount of a hydroxyl (OH—) impurity;
• applying heat to the mixture of powdered oxides in a gas atmosphere to melt the powdered oxides to form an oxide glass, said halide reacting with the hydroxyl to remove the hydrogen during the melt;
• and annealing the oxide glass to form the finished oxide glass that comprises a non-zero amount of said halide less than 0.5 mole percent, said finished oxide glass substantially free comprising less than 0.1 mole percent of each of the following,
• Sodium Oxide Na2O;
• Hydroxide OH—;
• and
• any other passive glass constituent having an absorption feature with an inherent absorption wavelength shorter than that of Tellurium (IV) oxide, wherein said glass exhibits an optical loss of less than 2 dB/m from 0.6 microns to 4.5 microns.