LOW-LOSS WAVEGUIDES FORMED IN HIGH-TRANSMISSION GLASS USING Ag-Na ION EXCHANGE

A backplane for a system that carries optical signals, comprising:

• a glass substrate having a top surface, the glass substrate comprising an alkali-aluminosilicate glass that comprises between 3 mol % and 15 mol % of Na2O and that has a concentration of Fe of 20 parts per million (ppm) or less;
• one or more buried Ag—Na ion-exchanged (IOX) regions formed in the glass substrate, wherein each of the one or more buried Ag—Na IOX regions has a maximum refractive index below the top surface of the glass substrate, wherein the one or more buried Ag—Na IOX regions and surrounding portions of the glass substrate define one or more Ag—Na IOX waveguides that each supports at least one propagating waveguide mode in a wavelength range between 800 nm and 1600 nm having an optical loss OL≤0.05 dB/cm and a birefringence magnitude |B|≤0.001 in the wavelength range;
• and
• an optical coupler operably disposed relative to the one or more Ag—Na IOX waveguides and configured to couple optical signals into and out of the one or more Ag—Na IOX waveguides.