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Questions related from Chao Shen
There are many definitions about plasma temperature, like electron temperature, ionization temperature, excitation temperature, atomic temperature, ionic temperature... What do they mean? I am...
01 January 2019 5,331 2 View
Hi everyone, I want to put some metallic particles with micrometer-sized (
09 September 2017 5,294 4 View
I use a step motor-based x-y microscope stage. I notice the paprameters in the datasheet include repeatability, accuracy and step size. Let the physical location to be X, so I understand the step...
04 April 2017 5,044 0 View
How to understand the physical image of polaron? I have searched it in wiki, but the concept is still hard to understand. Could anyone use some simple and easy to understand words to explain it?...
04 April 2017 9,497 4 View
I want to get 400nm from the 800nm laser using the BBO crystal, however, the conversion efficiency is quite low. In my case, the 800 nm pulse is with the rep. rate of 80MHz and average power of...
03 March 2017 6,070 20 View
Can anyone suggest some textbooks about scientific instrument design？Thanks!
02 February 2017 7,356 2 View
In what case can the plasma be treated as the ideal gas? The plasma, more specifically, is induced during a laser ablation event.
11 November 2016 9,239 3 View
what is the bandgap of PbWO4?
06 June 2016 1,699 3 View
what is coulombic screening? Any reference? Thanks!
11 November 2015 4,387 1 View
how to accurately measure a laser beam with a radius less than 1 micrometer (um)?
08 August 2015 733 0 View
what is Scanning photocurrent microscopy ? Any reference will be helpful, thank you!
06 June 2015 4,378 0 View
Sometimes I feel tired for experiments and formulas. how to train our interests for scientific research for a whole life?
02 February 2015 5,454 1 View
do anyone knows about the software which can simulate the laser ablation induced stress in materials? thanks!
01 January 2015 597 5 View
how to calculate the stress value according to the photoelastic image?
01 January 2015 323 4 View
I know that the polarized microscope can observe the location of stressed area of a solid, however, how can it measure it quantitatively? Any formulae?
01 January 2015 1,017 6 View
see above. the main characters i concern are the speed, size and direction. however, the speed of these particles are too fast to be resolved by normal cameras. what are the useful methods to...
11 November 2014 3,255 14 View
what is the bandgap of Nacl crystal?
11 November 2014 1,444 0 View
where can i find typical physical parameters about optical materials? such as melting point ,boiling point, critical mechanical strength?
11 November 2014 721 2 View
I want to perform a darkfield microscopy, but the commercial darkfield microscopy is not suitable because I want a collimated illuminating light rather than a condensed light. I want to use a...
10 October 2014 4,749 9 View
I want to analyse tracks of solid particles which are produced by laser-induced ablation of glass. I think that some aerodynamics knowledge will help. I want those especially focusing on the...
09 September 2014 9,997 1 View
See above.
09 September 2014 2,165 8 View
how to decide the bandgap of a solid material?
09 September 2014 6,441 11 View
When the glass is broken down (damage on surface ) by an intense ns laser pulse, the plasma will be launched simultaneously. However, this fast expanding plasma will induce a back pressure in the...
08 August 2014 9,915 11 View
Sedov blast formula: R=a*(E/p)^1/(2+n)*t^2/(2+n); I want to calculate the deposition energy E by fitting between R and t. What are the units of R, t and p when using this formula? And the...
08 August 2014 5,180 13 View
I use a thorlabs Photodetector (DET10A) to measure a 1064nm pulse width(about 10 ns according to the manufacture). However, just as shown in figure 1, the width is about 500us and the rise part is...
07 July 2014 6,759 4 View
Seeking an insight on this.
06 June 2014 7,390 4 View
Visio is the most common when one needs to draw a schematic diagram, however, it does not look very good. What software can you recommend to replace visio?
05 May 2014 3,378 2 View
I want to perform a pump-probe experiment with a ps probe light. so, what kind of camera I should buy? i have noticed that some ccd chip say that global shutter but with a progressive readout...
04 April 2014 2,045 3 View
What is the difference between IR spectroscopy and Raman spectroscopy? Does the central force network model suit both?
03 March 2014 1,602 10 View
What is drude model? Can you explain it in detail?
03 March 2014 9,011 23 View
Raman spectroscopy is very useful for material structure analysis. However, some questions still bother me: 1. As shown in the attached figure, there are 2 peaks in the 0-200 cm-1. However, few...
03 March 2014 5,168 5 View
In FTIR spectroscopy, there are two modes , which are reflectivity and transmissivity measurements respectively. what is the difference between them? Will the peak be different?
03 March 2014 1,819 3 View
What do the terms 'stiffer' and 'soften' in infrared spectroscopy mean? For example, do they make the frequency larger or smaller?
02 February 2014 5,721 5 View
What does the word "under-coordinated atom" mean? For example,under-coordinated silicons or oxygens?
01 January 2014 4,902 5 View
