Glass materials for optical gain media and infrared optics comprising rare earth oxide glass compositions

Abstract

This invention relates to the use of novel glass materials comprising rare earth aluminate glasses (REAl™ glasses) in the gain medium of solid state laser devices that produce light at infrared wavelengths, typically in the range 1000 to 3000 nm and for infrared optics with transmission to approximately 5000 nm in thin sections. The novel glass materials provide stable hosts for trivalent ytterbium (Yb 3+ ) ions and other optically active species or combinations of optically active species that exhibit fluorescence and that can be optically excited by the application of light. The glass gain medium can be configured as a waveguide or placed in an external laser cavity, or otherwise arranged to achieve gain in the laser waveband and so produce laser action.

1 . An optical gain medium comprising a bulk single phase glass comprising: 
 (a) 27 to 50 molar % RE 2 O 3 ; and    (b) 50 to 73 molar % Al 2 O 3 ;    where RE is one or more elements selected from the group consisting of Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.    
     
     
         2 . The optical gain medium of  claim 1  used in a manner such that gain is generated by application of light in the wavelength range from 970-990 nm.  
     
     
         3 . The optical gain medium of  claim 1  wherein gain is generated by electronic transitions of Yb.  
     
     
         4 . The optical gain medium of  claim 1  wherein gain is generated by electronic transitions of Er.  
     
     
         5 . The optical gain medium of  claim 1  wherein gain is generated by electronic transitions of Tm.  
     
     
         6 . The optical gain medium of  claim 1  wherein gain is generated by electronic transitions of Ho.  
     
     
         7 . An optical gain medium consisting essentially of a bulk single phase glass comprising one or more rare earth oxides, aluminum oxide and silicon dioxide wherein the composition lies substantially within the heptagonal region of the ternary composition diagram of the rare earth oxide-alumina-silica system defined by points having the following molar percent compositions: 1% RE 2 O 3 , 59% Al 2 O 3  and 40% SiO 2 ; 1% RE 2 O 3 , 71% Al 2 O 3  and 28% SiO 2 ; 23% RE 2 O 3  and 77% Al 2 O 3 ; 50% RE 2 O 3  and 50% Al 2 O 3 ; 50% RE 2 O 3  and 50% SiO 2 ; 33% RE 2 O 3 , 33.33% Al 2 O 3  and 33.33% SiO 2 ; and 16.67% RE 2 O 3 , 50% Al 2 O 3  and 33.33% SiO 2 .  
     
     
         8 . The optical gain medium of  claim 7  used in a manner such that gain is generated by application of light in the wavelength range from 970-990 nm.  
     
     
         9 . The optical gain medium of  claim 7  wherein gain is generated by electronic transitions of Yb.  
     
     
         10 . The optical gain medium of  claim 7  wherein gain is generated by electronic transitions of Er.  
     
     
         11 . The optical gain medium of  claim 7  wherein gain is generated by electronic transitions of Tm.  
     
     
         12 . The optical gain medium of  claim 7  wherein gain is generated by electronic transitions of Ho.  
     
     
         13 . The optical gain medium of  claim 1  wherein the REAl™ glass is formed by casting of a molten material.  
     
     
         14 . The optical gain medium of  claim 7  wherein the REAl™ glass is formed by casting of a molten material.  
     
     
         15 . An optical material consisting essentially of a bulk single phase glass comprising: 
 (a) 27 to 50 molar % RE 2 O 3 ; and    (b) 50 to 73 molar % Al 2 O 3 ;    where RE is one or more elements selected from the group consisting of Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu and wherein the glass is formed by casting of a molten material.    
     
     
         16  An optical material consisting essentially of a bulk single phase glass comprising one or more rare earth oxides, aluminum oxide and silicon dioxide wherein the composition lies substantially within the heptagonal region of the ternary composition diagram of the rare earth oxide-alumina-silica system defined by points having the following molar percent compositions: 1% RE 2 O 3 , 59% Al 2 O 3  and 40% SiO 2 ; 1% RE 2 O 3 , 71% Al 2 O 3  and 28% SiO 2 ; 23% RE 2 O 3  and 77% Al 2 O 3 ; 50% RE 2 O 3  and 50% Al 2 O 3 ; 50% RE 2 O 3  and 50% SiO 2 ; 33.33% RE 2 O 3 , 33.33% Al 2 O 3  and 33.33% SiO 2 ; and 16.67% RE 2 O 3 , 50% Al 2 O 3  and 33.33% SiO 2 ; 
 where RE is one or more elements selected from the group consisting of Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Th, Dy, Ho, Er, Tm, Yb and Lu and wherein the glass is formed by casting of a molten material.