Limits...
Observation of tunable nonlinear effects in an analogue of superconducting composite right/left hand filter.

Liu H, Lei J, Jiang H, Guan X, Ji L, Ma Z - Sci Rep (2015)

Bottom Line: Artificial structures with negative permittivity or permeability have attracted significant attention in the science community because they provide a pathway for obtaining exotic electromagnetic properties not found in natural materials.However, any future effort in creating tunable structures would require knowledge of nonlinear properties.Its nonlinear effects on temperature and power are studied by theoretical analysis and experiments.

View Article: PubMed Central - PubMed

Affiliation: Department of Information Engineering, East China Jiaotong University, Nanchang, 330013, China.

ABSTRACT
Artificial structures with negative permittivity or permeability have attracted significant attention in the science community because they provide a pathway for obtaining exotic electromagnetic properties not found in natural materials. At the moment, the great challenge of these artificial structures in microwave frequency exhibits a relatively large loss. It is well-known that superconducting thin films have extremely low surface resistance. Hence, it is a good candidate to resolve this constraint. Besides, the reported artificial structures with negative permittivity or permeability are mainly focusing on linear regime of wave propagation. However, any future effort in creating tunable structures would require knowledge of nonlinear properties. In this work, a tunable superconducting filter with composite right/left-hand transmission property is proposed and fabricated. Its nonlinear effects on temperature and power are studied by theoretical analysis and experiments.

No MeSH data available.


Related in: MedlinePlus

Insertion loss /S21/ characteristics at different operating temperature./S21/ is the value of S-parameter S21 (insertion loss). Four curves shown in this figure are insertion loss characteristics at different operating temperatures (65 K, 77 K, 100 K, 298 K).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4595847&req=5

f6: Insertion loss /S21/ characteristics at different operating temperature./S21/ is the value of S-parameter S21 (insertion loss). Four curves shown in this figure are insertion loss characteristics at different operating temperatures (65 K, 77 K, 100 K, 298 K).

Mentions: To further clarify microwave properties of HTS CRLH filter and make the most of superconducting properties, it is essential to understand the temperature dependence of frequency responses. Figure 6 shows the experimental frequency responses at different operating temperatures. As can be seen, the fabricated HTS CRLH filter has a steady performance when operating temperature is less than the critical temperature Tc (77 k). On the other hand, the bandpass performance from 1.42 to 2.16 GHz deteriorates when operating temperature is greater than the critical temperature Tc. This is attributed to the improved surface resistance (Rs). Generally, the relation between Rs and temperature appears to be nonlinear and is shown in Methods. In superconducting technology, surface resistance Rs is extremely low when operating temperature is less than the critical temperature Tc (77 k). However, when operating temperature increases to above the critical temperature Tc, surface resistance (Rs) of the HTS film is improved dramatically. The enlarged surface resistance (Rs) will improve attenuation factor α, as shown in Fig. 7. In addition, from Fig. 6, it also can be found that the HTS CRLH filter has both bandpass performance (temperature < 77 K) and bandstop performance (temperature > 100 K). This HTS device is a good candidate for the applications of superconductor switch. Off and on states of this CRLH filter can be transformed by changing the operating temperature.


Observation of tunable nonlinear effects in an analogue of superconducting composite right/left hand filter.

Liu H, Lei J, Jiang H, Guan X, Ji L, Ma Z - Sci Rep (2015)

Insertion loss /S21/ characteristics at different operating temperature./S21/ is the value of S-parameter S21 (insertion loss). Four curves shown in this figure are insertion loss characteristics at different operating temperatures (65 K, 77 K, 100 K, 298 K).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4595847&req=5

f6: Insertion loss /S21/ characteristics at different operating temperature./S21/ is the value of S-parameter S21 (insertion loss). Four curves shown in this figure are insertion loss characteristics at different operating temperatures (65 K, 77 K, 100 K, 298 K).
Mentions: To further clarify microwave properties of HTS CRLH filter and make the most of superconducting properties, it is essential to understand the temperature dependence of frequency responses. Figure 6 shows the experimental frequency responses at different operating temperatures. As can be seen, the fabricated HTS CRLH filter has a steady performance when operating temperature is less than the critical temperature Tc (77 k). On the other hand, the bandpass performance from 1.42 to 2.16 GHz deteriorates when operating temperature is greater than the critical temperature Tc. This is attributed to the improved surface resistance (Rs). Generally, the relation between Rs and temperature appears to be nonlinear and is shown in Methods. In superconducting technology, surface resistance Rs is extremely low when operating temperature is less than the critical temperature Tc (77 k). However, when operating temperature increases to above the critical temperature Tc, surface resistance (Rs) of the HTS film is improved dramatically. The enlarged surface resistance (Rs) will improve attenuation factor α, as shown in Fig. 7. In addition, from Fig. 6, it also can be found that the HTS CRLH filter has both bandpass performance (temperature < 77 K) and bandstop performance (temperature > 100 K). This HTS device is a good candidate for the applications of superconductor switch. Off and on states of this CRLH filter can be transformed by changing the operating temperature.

Bottom Line: Artificial structures with negative permittivity or permeability have attracted significant attention in the science community because they provide a pathway for obtaining exotic electromagnetic properties not found in natural materials.However, any future effort in creating tunable structures would require knowledge of nonlinear properties.Its nonlinear effects on temperature and power are studied by theoretical analysis and experiments.

View Article: PubMed Central - PubMed

Affiliation: Department of Information Engineering, East China Jiaotong University, Nanchang, 330013, China.

ABSTRACT
Artificial structures with negative permittivity or permeability have attracted significant attention in the science community because they provide a pathway for obtaining exotic electromagnetic properties not found in natural materials. At the moment, the great challenge of these artificial structures in microwave frequency exhibits a relatively large loss. It is well-known that superconducting thin films have extremely low surface resistance. Hence, it is a good candidate to resolve this constraint. Besides, the reported artificial structures with negative permittivity or permeability are mainly focusing on linear regime of wave propagation. However, any future effort in creating tunable structures would require knowledge of nonlinear properties. In this work, a tunable superconducting filter with composite right/left-hand transmission property is proposed and fabricated. Its nonlinear effects on temperature and power are studied by theoretical analysis and experiments.

No MeSH data available.


Related in: MedlinePlus