1. DALHM MEETING July 29-30, 2004 FORTH Heraklion, Crete, GREECE
29/07/2004
DALHM Meeting

2. SRR and Closed SRR transmission measurements.
Outline
SRR and Closed SRR transmission measurements.
True left-handed transmission band for 1D CMM.
2D CMM Transmission Measurements.
Negative refraction of
-1D CMM Wedge structures.
-2D CMM Wedge structures.
Phase measurements of 1D CMM structures.
29/07/2004
DALHM Meeting

3. Parameters of SRR Structuresd
Single SRR Parameters:
r1 = 2.5 mm
r2 = 3.6 mm
d = w = 0.2 mm
t = 0.9 mm t r2 r1 w
Periodic SRR Medium Parameters:
ax = ay =8.8 mm
az = 6.5 mm
Nx = 5
Ny = 15
Nz = 20 y z x
29/07/2004
DALHM Meeting

4. Parameters of Wire Structures Continuous wire structurey z x
L=12 cm
Periodic Wire Medium Parameters:
ax = 8.8 mm
az = 6.5 mm
Nx = 5
Nz = 20
r = 0.9 mm
Continuous wire structure
(Same with SRR Medium)
29/07/2004
DALHM Meeting

5. SRR, Closed SRR and CMM
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DALHM Meeting

6. Experimental Setup for Transmission Measurements
Network Analyzer
8510C
29/07/2004
DALHM Meeting

7. SRR and Closed SRR Transmission Spectrum
A bandgap in the transmission spectrum of SRR medium may be due to negative  or negative μ or due to the periodicity. The ambiguity can be lifted by using a structure in which the splits in the ring resonators are closed (CSRR). CSRR will destroy the magnetic resonance but still keep the electric resonance. A gap present in SRR but not in CSRR will then correspond to μ < 0.
29/07/2004
DALHM Meeting

8. SRR’s Dielectric Response and Plasma Frequency Shift
SRRs exhibit also resonant electric response. The behavior is similar to that of a periodic cut-wire medium. As a result, the SRRs contribute to the effective permittivity of the CMM, causing a downward shift on the plasma frequency determined solely from wire structures. To demonstrate this effect, a CMM consisting of periodic alternating layers of CSRRs and wires is used.
29/07/2004
DALHM Meeting

9. 1D CMM Transmission Spectrum
The CMM structure allows propagation of EM waves between 3.6 and 4.1 GHz, where both  and μ are negative. The CMM pass band exactly coincides with the stop band of SRR. The transmission peak at 3.9 GHz is -1.2 dB.
This work is submitted to Optics Letters.
29/07/2004
DALHM Meeting

10. 5 Layer 2D CMM Structure ax = ay = az = 9.3 mm Nx = 5 Ny = 20 Nz = 40
Periodic SRR Medium Parameters:
ax = ay = az = 9.3 mm
Nx = 5
Ny = 20
Nz = 40 x y z
5 unit cells and 4 perpendicular boards in the propagation direction.
29/07/2004
DALHM Meeting

11. 2D CMM Transmission Spectrum
A transmission peak for 2D 5 Layer CMM is observed inside the bandgap of SRR. Peak value is dB at 3.92 GHz.
29/07/2004
DALHM Meeting

12. 1D Wedge Structure # of Layers at x direction = 39z x
# of Layers at x direction = 39
# of Layers at y direction = 20
Maximum # of Layer at z direction = 15
Minimum # of Layer at z direction = 3
Average # of Layer at z direction = 9
29/07/2004
DALHM Meeting

13. 1D Wedge Structure Top view z y x
Wedge is constructed with a spacing of 6.5 mm at x direction. 3 layers at x direction has same number of layers at z direction. Then number of layers at z direction is reduced one which can be also called 3 by 1 structure.
29/07/2004
DALHM Meeting

14. θ=250 1D Wedge Structure Positive Refraction Negative Refraction
1D wedge structure has an angle of 250.
29/07/2004
DALHM Meeting

15. Experimental Setup for Negative Refraction Measurements using Wedge Structures
Two horn antennas are used in the experiment. Transmitter antenna is 2λ away from the surface of CMM structure. Receiver antenna, at a distance 7λ away from the oblique surface, is attached to a rotating arm to achieve angular scanning.
29/07/2004
DALHM Meeting

16. 1D Wedge Refraction Spectrum
EM waves are refracted mostly at negative angles at interested frequency range.
29/07/2004
DALHM Meeting

17. 1D Wedge Refraction Spectrum
29/07/2004
DALHM Meeting

18. θ=260 2D Wedge Structure x z y # of Layers at x direction = 34
# of Layers at y direction = 20
Maximum # of Layer at z direction = 19
Minimum # of Layer at z direction = 3
Average # of Layer at z direction = 11
Wedge is constructed with a spacing of 9.3 mm at x direction. 2 layers at x direction has same number of layers at z direction. Then number of layers at z direction is reduced one.
29/07/2004
DALHM Meeting

19. 2D Wedge Refraction Spectrum
EM waves are refracted mostly at negative angles at interested frequency range.
29/07/2004
DALHM Meeting

20. 2D Wedge Refraction Spectrum
29/07/2004
DALHM Meeting

21. Experimental Setup for Transmission Measurements
Network Analyzer
8510C
29/07/2004
DALHM Meeting

22. Transmission of Right-Handed part
29/07/2004
DALHM Meeting

23. Phase Data for Right-Handed part
Phases of different number of layers at the right-handed frequency region of the spectrum. Note that phase increases with the increasing number of layers as expected.
29/07/2004
DALHM Meeting

24. Transmission of Left-Handed part
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DALHM Meeting

25. Phase Data for Left-Handed part
Phases of different number of layers at the left-handed frequency region of the spectrum. Note that phase decreases with the increasing number of layers.
29/07/2004
DALHM Meeting

26. Phase Difference for Left-Handed part
Phase differences between different number of layers. Negative phase difference is observed.
29/07/2004
DALHM Meeting

27. Phase Difference for Left-Handed part
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DALHM Meeting

28. Phases of two adjacent number of layered CMMs
Change of phases throughout the spectrum is seen easily. After 4.3 GHz material behaves as a right-handed material.
29/07/2004
DALHM Meeting

29. Phases of two adjacent number of layered CMMs
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DALHM Meeting

30. 100 GHz process and measurement.
Future Work
100 GHz process and measurement.
Negative Refraction measurements using a 2D CMM Slab.
Phase Measurements of 2D CMM structures.
29/07/2004
DALHM Meeting