4. 𝑑 𝑑𝑠 (𝑛 𝑑𝑥 𝑑𝑠 )= 𝜕𝑛 𝜕𝑥
𝑑 𝑑𝑠 (𝑛 𝑑𝑦 𝑑𝑠 )= 𝜕𝑛 𝜕𝑦
𝑑 𝑑𝑠 (𝑛 𝑑𝑥 𝑑𝑠 )= 𝜕𝑛 𝜕𝑧

8. Example : Invisible Cloak?
I would like to start my talk with a simple question.
Q:in the nature, Is there any material which make an object to be invisible like magic cloak in the movie harry potter ?
No natural metaterials can do…

9. Question
Question
Answer
Maxwell’s equation is preserved

10. However, when the transformation is a conformal mapping,
Q :Scale factor
However, when the transformation is a conformal mapping,
ε and μ are scalar

12. Invisible Cloak
Sphere Cloaking
Cylinder Cloaking

13. Invisible Cloak

14. Invisible Cloak First demonstration of Invisible cloak실재
D. Schurig et al., Science 10, 977 (2006)

15. Invisible Cloak If we can control refractive index of material freely
Transformation optics
If we can control refractive index of material freely
…….
Nature Mat. 2009
If we can controlled refractive index of material freely, we can make invisible cloak, because we can manipulate the Space and Time in the viiew point of light wave with the refrative index.
Metamaterial can do it…