Hi,

I found something very interesting in PL result of synthesized CsI (cesium iodide) crystal. When using excitation wavelength of 256 nm (generated by Xeon flash source) the sharp emission peak was obtained.

In my understanding, CsI will show broad emission peak in range over 100 nm, however, my PL result shows a narrow emission peak as shown in attach file. What is happening?

Thanks for your help