Microwave properties of low-loss polymers at cryogenic temperatures

Jacob, Mohan V.; Mazierska, J.; Leong, Kenneth; Křupka, J.

doi:10.1109/22.982226

Cited by 33 publications

(22 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Anisotropic permittivity values t = 170 and z = 240 [27] give ε d (TiO 2 ) = 141 for rutile. For the PTFE phase, the value of ε d (PTFE) = 2.1 [29] was used. At cryogenic temperatures the loss tangent of PTFE is tanδ d (PTFE) = 5 · 10 −6 [29], and the loss tangent of rutile is tanδ d (TiO 2 ) = 1.7 · 10 −6 [27].…”

Section: A1 Permittivity Of the Ferroelectricmentioning

confidence: 99%

Tunability of Granular Ferroelectric Dielectric Composites

Jylhä¹,

Sihvola²

2008

PIER

View full text Add to dashboard Cite

Abstract-Electrical tunability of a composite consisting of small ferroelectric spheres randomly dispersed into a dielectric background is studied. A new method to calculate the effective permittivity of such a nonlinear composite is introduced. The method is based on the Bruggeman effective medium theory and a specific model for the nonlinear permittivity of the ferrite. The resulting tunability (defined as a measure of the change in the permittivity due to the bias field) is a continuous function of the volume fraction of the ferroelectric material phase in the composite. As an example, SrTiO 3 is studied with two different nontunable background materials.

show abstract

Section: A1 Permittivity Of the Ferroelectricmentioning

confidence: 99%

Tunability of Granular Ferroelectric Dielectric Composites

Jylhä¹,

Sihvola²

2008

PIER

View full text Add to dashboard Cite

show abstract

“…When a HTS thin film with surface resistance value of R SHTS is under test, the measurement error R S caused by variation of loss tangent [12] 15 m [10] of the sapphire rods in the two probes is calculated, from (1), (3), and (5), as…”

Section: Design Principlementioning

confidence: 99%

“…The Fig. 2 Picture of the four devices (a) and IIDM (b) Two-resonator device value of tanδ of Teflon is given in [12] and surface resistance of silver is given in [10]. TE 011+δ with resonance frequency at 12 GHz is chosen to be the working mode in IIDM devices.…”

Section: Design and Fabrication Of The Resonatormentioning

confidence: 99%

An Efficient and Accurate Method for HTS Surface Resistance Measurement

Cheng¹,

Chen²,

Bu³

et al. 2015

J Supercond Nov Magn

View full text Add to dashboard Cite

A new way to design resonator for efficiently measuring surface resistance (R S ) of high-temperature superconductor (HTS) thin films with low uncertainty based on improved image dielectric method is developed in this paper. Simple formula is given to evaluate measurement error caused by the variation of tanδ of sapphire rod. According to the formula, this error could be decreased by choosing appropriate size of sapphire rod. Three resonators using improved image dielectric method were designed based on this new way. Interlaboratory round robin test was performed with the aim of investigating the measurement uncertainty. The round robin test shows that the relative uncertainties are no more than 12.6 % which is less than 20 % the relative uncertainty value specified in international standard on HTS thin film R S measurement. As far as the authors know, these are the most efficient devices to measure the R S of HTS thin film with equal uncertainty.

show abstract

“…The dielectric resonator technique is typically used for the microwave characterisation of dielectric materials [8][9][10][11]. Among the different types of dielectric resonators, HakkiColeman dielectric resonator (HCDR) and dielectric post resonators (DPR) are commonly used to characterise rod shaped dielectric materials at microwave frequencies [8][9][10].…”

Section: Experimental Techniquesmentioning

confidence: 99%

Understanding the Fundamental Material Constants in Microwave Measurement

Jacob

2009

Ferroelectrics

View full text Add to dashboard Cite

Microwave characterisation of dielectric materials is vital to implement the material in communication devices and circuits. The microwave characterisation parameters are the dielectric constant, loss tangent, Q 0 × f 0 , temperature coefficient of frequency and temperature coefficient of permittivity. This paper examines the microwave characterisation data of four different dielectric materials. From several experiments on different dielectric materials, it has been concluded that the concept of using Q 0 × f 0 and temperature coefficient of frequency, as a material property will not reflect on material's fundamental behaviour. On the other hand, it has been interesting to note that the temperature coefficient of permittivity of a material is a constant irrespective of the measurement technique and hence it is a material parameter. The studies on temperature dependent permittivity will reveal the knack of a material to operate as a frequency stable circuit or device.

show abstract

Microwave properties of low-loss polymers at cryogenic temperatures

Cited by 33 publications

References 13 publications

Tunability of Granular Ferroelectric Dielectric Composites

Tunability of Granular Ferroelectric Dielectric Composites

An Efficient and Accurate Method for HTS Surface Resistance Measurement

Understanding the Fundamental Material Constants in Microwave Measurement

Contact Info

Product

Resources

About