Orhan Kıbrıslı

11 Questions 16 Answers 0 Followers

Questions related from Orhan Kıbrıslı

What is the difference between quantum yield and quantum efficiency for rare earth ion based photoluminescent material?

Some articles say they are same but some of them say they are different, I am pretty confused.

01 January 2020 9,610 8 View

Why up-conversion quantum yield(PLQY) values are quite low compared to down-conversion PLQY values?

Most of the articles report PLQY values below %10 for systems radiates through up-conversion mechansim while down-conversion PLQY values reach up to 80-90 %. Is there a theoretical limit?

01 January 2020 475 8 View

Is that possible to make a yellow laser by using a medium which emits red (600nm) and green (550 nm) photons upon UV excitation?

Well a yellow laser should be around 575-580 nm. Concurrently, mixture of green and red photons are also looks yellow. So can we call it as a laser or it will be just a high-powered yellow flash...

09 September 2019 6,085 6 View

Direct or indirect band gap for nano glass composites?

I am trying to calculate band gap energies of my heavy metal oxide glass samples but I am confused to choose among direct or indirect band gap energies. My samples have amorphous matrix and also...

02 February 2019 9,229 7 View

Is there any other reliable synthesizing method for tellurite glasses except sol-gel and conventional melt-quenching technique?

Especially better than melt-quenching.

02 February 2019 3,389 2 View

I am trying to calculate Judd-Ofelt parameters for Dy3+ doped tellurite system and I am really stuck with its math. Can someone help?

Actually I am asking for a calculation tool or Excel sheet so I can compare my calculation or I can just adapt it to my work. I think I calculated measured oscilltor strengths but I am not sure...

10 October 2018 4,560 9 View

Which one is better for rare-earth doped glasses long decay time or short decay time?

I have Dy3+ doped glass samples which exhibit lifetime like 100-300 microseconds. When I look to the conventional phosphors such as Ce:YAG they have lifetime values like 20-100 nanoseconds.

10 October 2018 1,318 3 View

How to decide fixed emission wavelength for a photoluminescence excitation (PLE) measurement?

For example I have a glassy sample which is doped with Dy+3 ions. I am trying to find the best excitation wavelength for my photoluminescence (PL) measurements. For this purpose I perform a...

01 January 2018 8,810 6 View

Is there a special technique to get optical microscope images of transparent glass samples?

Samples are highly transparent silicale glasses. I'm trying to get images by reflected light microscopy from surface and cross-section.

02 February 2017 8,746 3 View

How do you homogenize and refine your silica glass melt in your platinum cruicible?

I'm in trouble with bubbles. My batch contains Sb2O3 and SnO2 and I am mixing my batch with magnetic stirrer in ethanol. Also I am drying my batch before first melting in order to avoid...

08 August 2016 6,305 7 View

What is the reason for the amorphous halo in XRD patterns? Does it have a relation to clusters in amorph structure?

All the amorph structures show this pattern but I couldn't find the exact reason for it.

10 October 2015 1,177 15 View