A Potential Candidate for Lamp Phosphor: Eu<sup>3+</sup> Activated K<sub>2</sub>Y<sub>2</sub>B<sub>2</sub>O<sub>7</sub>

<table>The relation of the concentration of Eu<sup>3+</sup> ions <svg height="16.6" id="M27" style="vertical-align:-2.73372pt" version="1.1" viewbox="0 0 45.150002 16.6" width="45.150002" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> and <svg height="16.6" id="M28" style="vertical-align:-2.73372pt" version="1.1" viewbox="0 0 59.575001 16.6" width="59.575001" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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q0 -41 38 -68.5t94 -27.5q69 0 106.5 31t37.5 80q0 52 -45 71q-33 13 -98 13z" id="x67"></path></g><g transform="matrix(.017,-0,0,-.017,23.81,12.162)"><path d="M300 -147l-18 -23q-106 71 -159 185.5t-53 254.5v1q0 139 53 252.5t159 186.5l18 -24q-74 -62 -115.5 -173.5t-41.5 -242.5q0 -130 41.5 -242.5t115.5 -174.5z" id="x28"></path></g><g transform="matrix(.017,-0,0,-.017,29.691,12.162)"><path d="M414 650l-6 -28q-63 -4 -78.5 -17.5t-27.5 -71.5l-77 -416q-11 -58 0.5 -71.5t77.5 -17.5l-5 -28h-275l8 28q63 4 79.5 18.5t27.5 70.5l80 416q11 57 -2 71t-81 18l6 28h273z" id="x1D43C"></path></g><g transform="matrix(.017,-0,0,-.017,37.12,12.162)"><path d="M368 703l-264 -866h-60l265 866h59z" id="x2F"></path></g><g transform="matrix(.017,-0,0,-.017,44.123,12.162)"><path d="M536 404q0 -17 -13.5 -31.5t-26.5 -14.5q-8 0 -15 10q-11 14 -25 14q-22 0 -67 -50q-47 -52 -68 -82l37 -102q31 -88 55 -88t78 59l16 -23q-32 -48 -68.5 -78t-65.5 -30q-19 0 -37.5 20t-29.5 53l-41 116q-72 -106 -114.5 -147.5t-79.5 -41.5q-21 0 -34.5 14t-13.5 37
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</svg> for the <sup>5</sup>D<sub>0</sub> → <sup>7</sup>F<sub>2</sub> transition in the K<sub>2</sub>Y<sub>2</sub>B<sub>2</sub>O<sub>7</sub> phosphor.</table>

Advances in Optical Technologies

fig5

Figure 5

Figure 5: A Potential Candidate for Lamp Phosphor: Eu<sup>3+</sup> Activated K<sub>2</sub>Y<sub>2</sub>B<sub>2</sub>O<sub>7</sub> 

Advances in Optical Technologies

A Potential Candidate for Lamp Phosphor: Eu3+ Activated K2Y2B2O7

Figure 5

A Potential Candidate for Lamp Phosphor: Eu³⁺ Activated K₂Y₂B₂O₇