????(Left-Handed Metamaterials)??????????

1
????(Left-Handed Metamaterials)??????????
Seminar I

• ??? ???
• ?? ??? ???
• ???? ?? ????
• 
  

2
????

• ???????(Left-Handed Metama-terials)?????
• ??????????
• ?????????

3
????(LHM)?????

• ????????,??????????????e????µ??????????????????
  ????(Helmholtz??)?
• 
  
• 
  (1)
• ??

4

• ?????µ?e????????????????,
  ?k2lt0,k???????(1)????,???????????

5

• ??????????????????S???,? ,
  ? ? ? ???????????????????,(??????????????)?
  ?????? ???,??????
• ????,????????????????(Negetive Index of
  Refraction Material)
• ??????,???????????????,???????????????

6
???????Snell??
?1
?2
Fig 2. (a) ??????????????????,????????????????????
(b) ??????????????????,???????????????(c)
????????,???????????????
7
???Doppler??

• ??????? w0 ??,???????v?????,??????????????????
  ???? w0?,???????,?????w0?????

Fig 3. ??????????Doppler??????
8
???Cerenkov?????

• ? Cerenkov ?????,???????????? v ??????,?????????
  ???,??? k (kkz/cosq)
  ????????v???,?kr ????????????????????????
• ?????????????,????????????????????,??????????????

Fig 4. ?????????????(a) Cerenkov??(b) ??
9
??????????
10
??????????
11
???????????

• ??????????????,????,???????
• ???? (Perfect Lens)??????
• ??????????(diffraction limit)
• ?x2?/k?
• ?????DVD?????????????????????
• ?????????,???????,????????,?????????

12

• ????????????
• ?????????????????????????,?????????????
  ?????????????????????,???????????????????????,????
  ?????????????????????

???? (Photonic Crystals)
13
????(PC)???????????????????????????,?????????,????
??,????????????????????,???????????????
Fig 11. Photonic Crystals (a), (b)
Holes-in-dielectric (c) rods-in-air
14
Fig 12 (a) Experimental setup (not to scale). (b)
Propagation vectors for positive and negative
refraction. (c) (f ) Microwave electric field
maps in the far field region. (c) Negative and
(e) positive refraction by the metallic PC prism
for the incident beam along G?K (incident angle
30? ). WF(wave front) with respect to refracting
surface. (d) Negative refraction for the incident
beam along G? M (incidence angle 60?). (f )
Positive refraction by a polystyrene prism. In
all the field maps, approximate area of each
field map is 43 40 cm2.
Parimi P., Lu W., et al. ,Phy. Rev. Lett.
,2004,92,127401
15

• ????? ???????????????????????????????,???????
  ?????????,??PC??????,??PC??????????????????????

16
??
??????????????????????????????,???????????????

• ?????(photolithography)
• ??????? (near-field optical microscopy)
• ???????? (wavelength-tunable filter)
• ????? (optical displays)

17
(No Transcript)
18
Fig 5. (A) A negative index metamaterial formed
by SRRs and wires deposited on opposite sides
lithographically on standard circuit board. The
height of the structure is 1 cm. (B) The power
detected as a function of angle in a Snells law
experiment performed on a Teflon sample (blue
curve) and a negative index sample (red curve).
Shelby R. ,Smith D.R. ,et al ,Science ,2001,292,77
19
Fig 6. Unit cell of the 901 HWD structure. The
direction of propagation of the electromagnetic
field is along the x axis, the electric field is
oriented along the z axis, and the magnetic field
is along the y axis. C0.025 cm, D0.030 cm,
G0.046 cm, H 0.0254 cm, L 0.33 cm, S 0.263
cm, T 17.010-4 cm, W 0.025 cm, and V 0.255 cm.
Fig 7. Schematic of the setup used in the
Snells law experiment showing the conical horn,
lens, sample, and waveguide detector. The
measurements were made in the focused and
collimated mode at 33 and 66 cm away from the
sample.
Parazzoli C. G. ,Greegor R. B. ,et al , Phys.
Rev. Lett. ,2003,90,107401
20
Fig 8. Surface plot of measured normalized Ez(r,f
). Refracted peaks by Teflon at 48.2(n1.4) and
is independent of frequency by the NIM ,
however, at 12.6GHz,-30.6 (n-1.0454) that are a
function of the frequency..
Fig 9. (a) Measured angular profile of the
normalized Ez(r), at f 12.6 GHz for detector
distances of 33 and 66 cm from the wedges. (b)
Measured 33 cm data compared to simulated results
at 33, 66, and 238 cm (100?)from the wedges.
21
Fig 10. Perfect lensing in action (A) the far
field and (B) the near field, translating the
object into a perfect image. (C) Microwave
experiments demonstrate that subwavelength
focusing is possible, limited only by losses in
the system. (D) Measured data compared to the
perfect results. Losses limit the resolution to
less than perfect but better than the diffraction
limit.
Grbic A. ,Eleftheriades G. , Phy. Rev. Lett.
,2004,92,117403
22
?mo-????? ?mp-??????? ?eo-?????? ?ep-???????
???0lt ?lt ?p,e???????????