anw, thanks for the explanantion, sir. but where does this explanation come from? is there any book as reference? i really need to read the book. thanks
Respected Sir, Can you please tell me mie scattering in solid? like when an incident light fall on the solid material then the light scatters as the diameter of solid increases. please explain the scattering of light with diameter of a solid material. Thank you.
Dear Sagar, In Mie theory, the scattering object is treated as a homogeneous entity with constant refractive index, which differs from the refractive index of the homogeneous medium that surrounds it. Whether the scattering object is gaseous, liquid or solid is irrelevant. The size dependence of the scattering is primarily a function of the particle diameter, and secondarily of the difference in refractive index between particle and medium: (1) Scattering efficiency increases with particle size; (2) As the particle diameter approaches, and surpasses, the wavelength of the scattered light, there will be a proportionately larger contribution of oscillatory behavior, as a function of wavelength and scattering angle. I recommend playing with some online Mie codes to get a better feel for that: www.philiplaven.com/mieplot.htm or omlc.org/calc/mie_calc.html One other thing to keep in mind: Mie theory, in its standard application, involves the scattering of light from dielectric particles. If you want to consider light scattering from metallic spheres, it is absolutely possible to use Mie theory but the boundary conditions for electric and magnetic field continuity at the particle surface will differ - and hence, the solutions to Mie theory will take a slightly different form. More advanced light scattering textbooks, like van de Hulst or Kerker, address that problem. See: books.google.com/books/about/Light_Scattering_by_Small_Particles.html?id=PlHfPMVAFRcC or www.sciencedirect.com/book/9780124045507/the-scattering-of-light-and-other-electromagnetic-radiation Bestregards, Martin
I want to characterize gold nanoparticles by Mie theory and I want to know the refractive index of gold nanoparticles to calculate the cross section, and other composites of crumb diffusion. I need you who helps me to find the refractive index or dielectric constant.
Hi Martin, Can you tell me where Figure 3 in the video comes from? I don't see it in Van De Hulst. Thanks! BTW, did you crawl thru all that in Van De Hulst? It's not the best writing. Must have taken some time. Kudos.
Great lecture. Thanks for sharing it. Please correct me if I am wrong but I think that in the slide where you introduced the Jones matrix you have a typo in the equation. ,The factor that you refer to as the spherical wave factor, should not depend on time. I think that the omega*t in the exponential should be changed to z.
Hi Jose, thanks for your positive feedback and the question. The omega*t term does need to be included as well as the kr term, because it describes a propagating wave that has both temporal and spatial dependence. I'd recommend checking out Chapter 2 in Hecht's "Optics" textbook, in particular equation 2.74 (www.polaritech.ir/wp-content/uploads/2016/12/Hecht-optics-5ed.pdf).
Hi Vinoth, These are also sometimes called WGM (Whispering Gallery Modes) or MDR (Morphology-Dependent Resonances). They occur whenever a standing wave can be established around the circumference of the sphere. You can read about them in these articles: thesis.library.caltech.edu/6857/4/Chapter_3.pdf and www.osapublishing.org/oe/abstract.cfm?uri=oe-16-21-16390&origin=search. -Martin
Thank you very much for the response and the references. I am going through these. I have come across something like this, "Particle resonance is generated by varying the size parameter (z), which is z = (2*pi*r*n)/lambda where r is the radius of the particle, n is the refractive index of the surrounding medium and lambda is the wavelength of the radiation. For what values of z, one can achieve resonance? Thanks a lot again.
I haven't gone through the math of that in detail. My guess would be that you'd want the circumference of the sphere to be an integral multiple of the wavelength of the light inside the particle. I'd read up on those papers, and look into Lord Rayleigh's analogous work on whispering modes of sound inside circular buildings. Let me know what you find out! Thanks.
Thank you very much. If that is the case (what you guessed), then the resonance condition will be achieved for particle of any size that matches the integral multiple of wavelength. I got this from one of the reviewers "The enhanced local field effects, could be discussed in terms of the Mie resonance for small spheres" That makes me to research on Mie resonance. I will certainly let you know whatever I come to know. Thanks a lot.
Yours truly: Martin Hunter, in the Biomedical Engineering Dept. at Tufts University (Medford, MA, USA). I use it for an Intro to Biophotonics course for undergrad and grad students.
Oh cool. Nice lecture. Much clearer than reading Bohren. BTW, what text are you showing on the pages? Also, is there a web page for the course still up?
Glad it was helpful! The full course material is only posted internally at Tufts, sorry. The text was primarily from van de Hulst (www.amazon.com/Light-Scattering-Small-Particles-Physics/dp/0486642283)
really nice explanation of Mie scattering. very helpful. Thank you so much.
TU Vienna
can we get the powerpoint presentation
@martin Hunter : can u please attach the PDF for Ur video
Thanks
Thanks for the great lecture...
At around 15 min, when you show S1[theta] and S2[theta], what does an and bn mean?
anw, thanks for the explanantion, sir. but where does this explanation come from? is there any book as reference? i really need to read the book. thanks
Radiative heat transfer ( modest ) chapter 11
@@khalidalhammadi9527 thanks haha I've graduated anyway
Respected Sir, Can you please tell me mie scattering in solid?
like when an incident light fall on the solid material then the light scatters as the diameter of solid increases. please explain the scattering of light with diameter of a solid material. Thank you.
Dear Sagar,
In Mie theory, the scattering object is treated as a homogeneous entity with constant refractive index, which differs from the refractive index of the homogeneous medium that surrounds it. Whether the scattering object is gaseous, liquid or solid is irrelevant. The size dependence of the scattering is primarily a function of the particle diameter, and secondarily of the difference in refractive index between particle and medium: (1) Scattering efficiency increases with particle size; (2) As the particle diameter approaches, and surpasses, the wavelength of the scattered light, there will be a proportionately larger contribution of oscillatory behavior, as a function of wavelength and scattering angle. I recommend playing with some online Mie codes to get a better feel for that: www.philiplaven.com/mieplot.htm or omlc.org/calc/mie_calc.html
One other thing to keep in mind: Mie theory, in its standard application, involves the scattering of light from dielectric particles. If you want to consider light scattering from metallic spheres, it is absolutely possible to use Mie theory but the boundary conditions for electric and magnetic field continuity at the particle surface will differ - and hence, the solutions to Mie theory will take a slightly different form. More advanced light scattering textbooks, like van de Hulst or Kerker, address that problem. See: books.google.com/books/about/Light_Scattering_by_Small_Particles.html?id=PlHfPMVAFRcC or www.sciencedirect.com/book/9780124045507/the-scattering-of-light-and-other-electromagnetic-radiation
Bestregards,
Martin
@@martincazador Thank you so Sir. This will be very helpful to me.
I want to characterize gold nanoparticles by Mie theory and I want to know the refractive index of gold nanoparticles to calculate the cross section, and other composites of crumb diffusion.
I need you who helps me to find the refractive index or dielectric constant.
Hi Martin, Can you tell me where Figure 3 in the video comes from? I don't see it in Van De Hulst. Thanks! BTW, did you crawl thru all that in Van De Hulst? It's not the best writing. Must have taken some time. Kudos.
Great lecture. Thanks for sharing it. Please correct me if I am wrong but I think that in the slide where you introduced the Jones matrix you have a typo in the equation. ,The factor that you refer to as the spherical wave factor, should not depend on time. I think that the omega*t in the exponential should be changed to z.
Hi Jose, thanks for your positive feedback and the question. The omega*t term does need to be included as well as the kr term, because it describes a propagating wave that has both temporal and spatial dependence. I'd recommend checking out Chapter 2 in Hecht's "Optics" textbook, in particular equation 2.74 (www.polaritech.ir/wp-content/uploads/2016/12/Hecht-optics-5ed.pdf).
Thanks a lot.
What is Mie Resonance?
Can you please explain?
Hi Vinoth,
These are also sometimes called WGM (Whispering Gallery Modes) or MDR (Morphology-Dependent Resonances). They occur whenever a standing wave can be established around the circumference of the sphere. You can read about them in these articles: thesis.library.caltech.edu/6857/4/Chapter_3.pdf and www.osapublishing.org/oe/abstract.cfm?uri=oe-16-21-16390&origin=search.
-Martin
Thank you very much for the response and the references. I am going through these. I have come across something like this,
"Particle resonance is generated by varying the size parameter (z), which is
z = (2*pi*r*n)/lambda
where r is the radius of the particle, n is the refractive index of the surrounding medium and lambda is the wavelength of the radiation.
For what values of z, one can achieve resonance?
Thanks a lot again.
I haven't gone through the math of that in detail. My guess would be that you'd want the circumference of the sphere to be an integral multiple of the wavelength of the light inside the particle. I'd read up on those papers, and look into Lord Rayleigh's analogous work on whispering modes of sound inside circular buildings. Let me know what you find out! Thanks.
Thank you very much. If that is the case (what you guessed), then the resonance condition will be achieved for particle of any size that matches the integral multiple of wavelength.
I got this from one of the reviewers
"The enhanced local field effects, could be discussed in terms of the Mie resonance for small spheres"
That makes me to research on Mie resonance.
I will certainly let you know whatever I come to know.
Thanks a lot.
Thank you very much!
Really helpful! Thank you.
Anyone know what University this is from? Who is the lecturer?
Yours truly: Martin Hunter, in the Biomedical Engineering Dept. at Tufts University (Medford, MA, USA). I use it for an Intro to Biophotonics course for undergrad and grad students.
Oh cool. Nice lecture. Much clearer than reading Bohren. BTW, what text are you showing on the pages? Also, is there a web page for the course still up?
Glad it was helpful! The full course material is only posted internally at Tufts, sorry. The text was primarily from van de Hulst (www.amazon.com/Light-Scattering-Small-Particles-Physics/dp/0486642283)