Superconductivity - Part 15: Electronic characteristic measurements - Intrinsic surface impedance of superconductor films at microwave frequencies

IEC 61788-15:2011 describes measurements of the intrinsic surface impedance (Zs) of HTS films at microwave frequencies by a modified two-resonance mode dielectric resonator method. The object of measurement is to obtain the temperature dependence of the intrinsic Zs at the resonant frequency f0.

Supraleitfähigkeit - Teil 15: Messungen der elektronischen Charakteristik - Oberflächenimpedanz von Supraleiterschichten bei Mikrowellenfrequenzen

Supraconductivité - Partie 15: Mesures de caractéristiques électroniques - Impédance de surface intrinsèque de films supraconducteurs aux fréquences micro-ondes

La CEI 61788-15:2011 décrit les mesures de l'impédance de surface intrinsèque (Zs) des films HTS aux fréquences micro-ondes par une méthode modifiée du résonateur diélectriques en mode deux résonances. L'objet de la mesure est d'obtenir la dépendance de l'impédance intrinsèque Zs vis-à-vis de la température à la fréquence de résonance f0.

Superprevodnost - 15. del: Meritve elektronskih karakteristik - Lastna površinska impedanca superprevodnih plasti pri mikrovalovnih frekvencah

Ta del standarda IEC 61788 opisuje meritve lastne površinske impedance (ZS) visokotemperaturnih superprevodnih (HTS) plasti pri mikrovalovnih frekvencah z metodo modificiranega dvoresonančnega dielektričnega resonatorja [13, 14]. Z meritvijo se ugotavlja temperaturna odvisnost lastne površinske impedance pri resonančni frekvenci f0. Razpon frekvence in debeline ter ločljivost meritev za lastno površinsko impedanco visokotemperaturnih superprevodnih plasti je: – frekvenca: do 40 GHz; – debelina plasti: večja od 50 nm; – ločljivost meritve: 0,01 mO pri 10 GHz. Poročati je treba o podatkih v zvezi z lastno površinsko impedanco pri izmerjeni frekvenci in pri prilagojeni frekvenci 10 GHz ob predpostavki pravila f2 za lastno površinsko upornost RS (f < 40 GHz) ter pravila f za lastno površinsko reaktanco XS za primerjavo.

General Information

Status
Published
Publication Date
15-Dec-2011
Technical Committee
Drafting Committee
Current Stage
6060 - Document made available
Due Date
16-Dec-2011
Completion Date
16-Dec-2011

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SLOVENSKI STANDARD
SIST EN 61788-15:2012
01-marec-2012

Superprevodnost - 15. del: Meritve elektronskih karakteristik - Lastna površinska

impedanca superprevodnih plasti pri mikrovalovnih frekvencah

Superconductivity - Part 15: Electronic characteristic measurements - Intrinsic surface

impedance of superconductor films at microwave frequencies
Supraleitfähigkeit - Teil 15: Messungen der elektronischen Charakteristik -
Oberflächenimpedanz von Supraleiterschichten bei Mikrowellenfrequenzen

Supraconductivité - Partie 15: Mesures de caractéristiques électroniques - Impédance de

surface intrinsèque de films supraconducteurs aux fréquences micro-ondes
Ta slovenski standard je istoveten z: EN 61788-15:2011
ICS:
17.220.20 0HUMHQMHHOHNWULþQLKLQ Measurement of electrical
PDJQHWQLKYHOLþLQ and magnetic quantities
29.050 Superprevodnost in prevodni Superconductivity and
materiali conducting materials
SIST EN 61788-15:2012 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN 61788-15:2012
---------------------- Page: 2 ----------------------
SIST EN 61788-15:2012
EUROPEAN STANDARD
EN 61788-15
NORME EUROPÉENNE
December 2011
EUROPÄISCHE NORM
ICS 29.050
English version
Superconductivity -
Part 15: Electronic characteristic measurements -
Intrinsic surface impedance of superconductor films at microwave
frequencies
(IEC 61788-15:2011)
Supraconductivité - Supraleitfähigkeit -
Partie 15: Mesures de caractéristiques Teil 15: Messungen der elektronischen
électroniques - Charakteristik -
Impédance de surface intrinsèque de films Oberflächenimpedanz von
supraconducteurs aux fréquences micro- Supraleiterschichten bei
ondes Mikrowellenfrequenzen
(CEI 61788-15:2011) (IEC 61788-15:2011)

This European Standard was approved by CENELEC on 2011-11-28. CENELEC members are bound to comply

with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard

the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on

application to the CEN-CENELEC Management Centre or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other

language made by translation under the responsibility of a CENELEC member into its own language and notified

to the CEN-CENELEC Management Centre has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus,

the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,

Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia,

Spain, Sweden, Switzerland and the United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Management Centre: Avenue Marnix 17, B - 1000 Brussels

© 2011 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Ref. No. EN 61788-15:2011 E
---------------------- Page: 3 ----------------------
SIST EN 61788-15:2012
EN 61788-15:2011 - 2 -
Foreword

The text of document 90/280/FDIS, future edition 1 of IEC 61788-15, prepared by IEC/TC 90

"Superconductivity" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as

EN 61788-15:2011.
The following dates are fixed:
(dop) 2012-08-28
• latest date by which the document has
to be implemented at national level by
publication of an identical national
standard or by endorsement
(dow) 2014-11-28
• latest date by which the national
standards conflicting with the
document have to be withdrawn

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such patent

rights.
Endorsement notice

The text of the International Standard IEC 61788-15:2011 was approved by CENELEC as a European

Standard without any modification.
---------------------- Page: 4 ----------------------
SIST EN 61788-15:2012
- 3 - EN 61788-15:2011
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application of this document. For dated

references, only the edition cited applies. For undated references, the latest edition of the referenced

document (including any amendments) applies.

NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD

applies.
Publication Year Title EN/HD Year
IEC 60050-815 2000 International Electrotechnical Vocabulary - -
(IEV) -
Part 815: Superconductivity
IEC 61788-7 2006 Superconductivity - EN 61788-7 2006
Part 7: Electronic characteristic
measurements - Surface resistance of
superconductors at microwave frequencies
---------------------- Page: 5 ----------------------
SIST EN 61788-15:2012
---------------------- Page: 6 ----------------------
SIST EN 61788-15:2012
IEC 61788-15
Edition 1.0 2011-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Superconductivity –
Part 15: Electronic characteristic measurements – Intrinsic surface impedance
of superconductor films at microwave frequencies
Supraconductivité –
Partie 15: Mesures de caractéristiques électroniques – Impédance de surface
intrinsèque de films supraconducteurs aux fréquences micro-ondes
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX X
ICS 29.050 ISBN 978-2-88912-710-8
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 7 ----------------------
SIST EN 61788-15:2012
– 2 – 61788-15  IEC:2011
CONTENTS

FOREWORD ........................................................................................................................... 4

INTRODUCTION ..................................................................................................................... 6

1 Scope ............................................................................................................................... 7

2 Normative references ....................................................................................................... 7

3 Terms and definitions ....................................................................................................... 7

4 Requirements ................................................................................................................... 8

5 Apparatus ......................................................................................................................... 9

5.1 Measurement equipment ......................................................................................... 9

5.2 Measurement apparatus .......................................................................................... 9

5.3 Dielectric rods ....................................................................................................... 13

5.4 Superconductor films and copper cavity ................................................................ 14

6 Measurement procedure ................................................................................................. 14

6.1 Set-up ................................................................................................................... 14

6.2 Measurement of the reference level....................................................................... 14

6.3 Measurement of the R of oxygen-free high purity copper ..................................... 14

6.4 Determination of the effective R of superconductor films and tanδ of

standard dielectric rods ......................................................................................... 17

6.5 Determination of the penetration depth .................................................................. 18

6.6 Determination of the intrinsic surface impedance ................................................... 20

7 Uncertainty of the test method ........................................................................................ 21

7.1 Measurement of unloaded quality factor ................................................................ 21

7.2 Measurement of loss tangent................................................................................. 21

7.3 Temperature .......................................................................................................... 22

7.4 Specimen and holder support structure ................................................................. 22

8 Test Report .................................................................................................................... 22

8.1 Identification of test specimen ............................................................................... 22

8.2 Report of the intrinsic Z values ............................................................................ 22

8.3 Report of the test conditions .................................................................................. 22

Annex A (informative) Additional information relating to clauses 1 to 8 ............................... 24

Annex B (informative) Uncertainty considerations ................................................................ 41

Bibliography .......................................................................................................................... 45

Figure 1 – Schematic diagram for the measurement equipment for the intrinsic Z of

HTS films at cryogenic temperatures .................................................................................... 10

Figure 2 – Schematic diagram of a dielectric resonator with a switch for thermal

connection ............................................................................................................................ 10

Figure 3 – Typical dielectric resonator with a movable top plate ............................................ 11

Figure 4 – Switch block for thermal connection ..................................................................... 12

Figure 5 – Dielectric resonator assembled with a switch block for thermal connection ........... 13

Figure 6 – A typical resonance peak. Insertion attenuation IA, resonant frequency f

and half power bandwidth ∆f are defined .......................................................................... 16

3dB

Figure 7 – Reflection scattering parameters S and S ...................................................... 18

11 22

Figure 8 – Definitions for terms in Table 5 ............................................................................ 22

Figure A.1 – Schematic diagram for the measurement system .............................................. 24

Figure A.2 – A motion stage using step motors ..................................................................... 25

---------------------- Page: 8 ----------------------
SIST EN 61788-15:2012
61788-15  IEC:2011 – 3 –

Figure A.3 – Cross-sectional view of a dielectric resonator ................................................... 26

Figure A.4 – A diagram for simplied cross-sectional view of a dielectric resonator ................ 30

Figure A.5 – Mode chart for a sapphire resonator ................................................................. 33

Figure A.6 – Frequency response of the sapphire resonator .................................................. 34

Figure A.7 – Q versus temperature for the TE and the TE modes of the sapphire
U 021 012

resonator with 360 nm-thick YBCO films ............................................................................... 35

Figure A.8 – The resonant frequency f versus temperature for the TE and TE
0 021 012

modes of the sapphire resonator with 360 nm-thick YBCO films ............................................ 35

Figure A.9 – The temperature dependence of the R of YBCO films with the

thicknesses of 70 nm to 360 nm measured at ~40 GHz ......................................................... 36

Figure A.10 – The temperature dependence of ∆λ for the YBCO films with the

thicknesses of 70 nm and 360 nm measured at ~40 GHz ...................................................... 36

Figure A.11 – The penetration depths λ of the 360 nm-thick YBCO film measured at

10 kHz by using the mutual inductance method and at ~40 GHz by using sapphire

resonator .............................................................................................................................. 37

Figure A.12 – The temperature dependence of the intrinsic surface resistance R of

YBCO films with the thicknesses of 70 nm to 360 nm measured at ~40 GHz ......................... 37

Figure A.13 – Comparison of the temperature-dependent value of each term in

Equation (A.35) for the TE mode of the standard sapphire resonator ................................ 38

021
Figure A.14 – Comparison of the temperature-dependent value of each term in

Equation (A.35) for the TE mode of the standard sapphire resonator ................................ 38

012

Figure A.15 – Temperature dependence of uncertainty in the measured intrinsic R of

YBCO films ........................................................................................................................... 39

Table 1 – Typical dimensions of a sapphire rod .................................................................... 14

Table 2 – Typical dimensions of OFHC cavities and HTS films .............................................. 14

Table 3 – Geometrical factors and filling factors calculated for the standard sapphire

resonator .............................................................................................................................. 17

Table 4 – Specifications of vector network analyzer .............................................................. 21

Table 5 – Type B uncertainty for the specifications on the sapphire rod ................................ 21

Table A.1 – Geometrical factors and filling factors calculated for the standard sapphire

resonator .............................................................................................................................. 31

Table B.1 – Output signals from two nominally identical extensometers ................................ 42

Table B.2 – Mean values of two output signals ..................................................................... 42

Table B.3 – Experimental standard deviations of two output signals...................................... 42

Table B.4 – Standard uncertainties of two output signals ...................................................... 42

Table B.5 – Coefficient of variations of two output signals..................................................... 43

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SIST EN 61788-15:2012
– 4 – 61788-15  IEC:2011
INTERNATIONAL ELECTROTECHNICAL COMMISSION
_____________
SUPERCONDUCTIVITY –
Part 15: Electronic characteristic measurements –
Intrinsic surface impedance of superconductor
films at microwave frequencies
FOREWORD

1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

all national electrotechnical committees (IEC National Committees). The object of IEC is to promote

international co-operation on all questions concerning standardization in the electrical and electronic fields. To

this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,

Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC

Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested

in the subject dealt with may participate in this preparatory work. International, governmental and non-

governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely

with the International Organization for Standardization (ISO) in accordance with conditions determined by

agreement between the two organizations.

2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international

consensus of opinion on the relevant subjects since each technical committee has representation from all

interested IEC National Committees.

3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

misinterpretation by any end user.

4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

transparently to the maximum extent possible in their national and regional publications. Any divergence

between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in

the latter.

5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

services carried out by independent certification bodies.

6) All users should ensure that they have the latest edition of this publication.

7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and

members of its technical committees and IEC National Committees for any personal injury, property damage or

other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and

expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC

Publications.

8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

indispensable for the correct application of this publication.

9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of

patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

International Standard IEC 61788-15 has been prepared by IEC technical committee 90:

Superconductivity.
The text of this standard is based on the following documents:
FDIS Report on voting
90/280/FDIS 90/283/RVD

Full information on the voting for the approval of this standard can be found in the report on

voting indicated in the above table.

This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

---------------------- Page: 10 ----------------------
SIST EN 61788-15:2012
61788-15  IEC:2011 – 5 –

A list of all parts of the IEC 61788 series, published under the general title Superconductivity,

can be found on the IEC website.

The committee has decided that the contents of this publication will remain unchanged until

the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data

related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates

that it contains colours which are considered to be useful for the correct

understanding of its contents. Users should therefore print this document using a

colour printer.
---------------------- Page: 11 ----------------------
SIST EN 61788-15:2012
– 6 – 61788-15  IEC:2011
INTRODUCTION
Since the discovery of high T superconductors (HTS), extensive research has been

performed worldwide on electronic applications and large-scale applications with HTS filter

subsystems based on YBa Cu O (YBCO) having already been commercialized [1] .
2 3 7-δ

The merits of using HTS films for microwave devices such as resonators, filters, antennas,

delay lines, etc., include i) possibility of microwave losses from HTS films being extremely low

and ii) no signal dispersion on transmission lines made of HTS films due to extremely low

microwave surface resistance (R ) [2] and frequency-independent penetration depth (λ) of

HTS films, respectively.

In this regard, when it comes to designing HTS-based microwave devices, it is important to

measure the surface impedance (Z ) of HTS films with Z = R + jX and X = ωμ λ (here ω

S S S S S 0

and μ denote the angular frequency and the permeability of vacuum, respectively, X , the

0 S

surface reactance, and X = ωμ λ is valid at temperatures not too close to the critical

S 0
temperature T of HTS films).

Various reports have been made on measuring the R of HTS films at microwave frequencies

with the typical R of HTS films as low as 1/100 - 1/50 of that of oxygen-free high-purity

copper (OFHC) at 77 K and 10 GHz. The R of conventional superconductors such as

niobium (Nb) could be easily measured by using Nb cavities by converting the resonator

quality factor (Q) to the R of Nb. However, such conventional measurement method could no

longer be applied to HTS films grown on dielectric substrates, with which it is basically

impossible to make all-HTS cavities. Instead, for measuring the R of HTS films, several

other methods have been useful, which include the microstrip resonator method [3], the

coplanar microstrip resonator method [4], the parallel plate resonator method [5] and the

dielectric resonator method [7-10]. Among the stated methods, the dielectric resonator

method has been very useful due to that the method enables to measure the R in a non-

invasive way and with accuracy. In 2002, the International Electrotechnical Commission (IEC)

published the dielectric resonator method as a measurement standard [11].

The test method given in this standard enables measurement not only of the intrinsic surface

resistance but also the intrinsic surface reactance of HTS films, regardless of the film’s

thickness, by using a single sapphire resonator that differs from the existing IEC standard

(IEC 61788-7:2006), which is limited to measuring the surface resistance of superconductor

films having a thicknesses of more than 3λ at the measured temperature by using two

sapphire resonators. In fact, the measured surface resistances of HTS films with different

thicknesses of less than 3λ mean effective values instead of intrinsic values, which cannot be

used for directly comparing the microwave properties of HTS films among one another [12,

13]. Use of a single sapphire resonator as suggested in this standard also makes it possible

to reduce uncertainty in the measured surface resistance that might result from using two

sapphire resonators with sapphire rods of even slightly different quality.

The test method given in this standard can also be applied to HTS coated conductors, HTS

bulks and other superconductors having established models for the penetration depth.

This standard is intended to provide an appropriate and agreeable technical base for the time

being to engineers working in the fields of electronics and superconductivity technology.

The test method covered in this standard has been discussed at the VAMAS (Versailles

Project on Advanced Materials and Standards) TWA-16 meeting.
___________
Numerals in square brackets refer to the Bibliography.
---------------------- Page: 12 ----------------------
SIST EN 61788-15:2012
61788-15  IEC:2011 – 7 –
SUPERCONDUCTIVITY –
Part 15: Electronic characteristic measurements –
Intrinsic surface impedance of superconductor
films at microwave frequencies
1 Scope

This part of IEC 61788 describes measurements of the intrinsic surface impedance (Z ) of

HTS films at microwave frequencies by a modified two-resonance mode dielectric resonator

method [13, 14] . The object of measurement is to obtain the temperature dependence of the

intrinsic Z at the resonant frequency f .
S 0

The frequency and thickness range and the measurement resolution for the intrinsic Z of

HTS films are as follows:
− frequency: up to 40 GHz;
− film thickness: greater than 50 nm;
− measurement resolution: 0,01 mΩ at 10 GHz.

The intrinsic Z data at the measured frequency, and that scaled to 10 GHz, assuming the f

rule for the intrinsic surface resistance R (f < 40 GHz) and the f rule for the intrinsic surface

reactance X for comparison, shall be reported.
2 Normative references

The following referenced documents are indispensible for the application of this document.

For dated references, only the edition cited applies. For undated references, the latest edition

of the referenced document (including any amendments) applies.

IEC 60050-815:2000, International Electrotechnical Vocabulary – Part 815: Superconductivity

IEC 61788-7:2006, Superconductivity – Part 7: Electronic characteristic measurements –

Surface resistance of superconductors at microwave frequencies
3 Terms, definitions and general concepts
3.1 Terms and definitions

For the purposes of this document, the definitions given in IEC 60050-815, one of which is

repeated here for convenience, apply.
3.1.1
surface impedance

impedance of a material for high frequency electromagnetic wave which is constrained to the

surface of the material in case of metals and superconductors

NOTE The surface impedance governs the thermal losses of superconducting RF cavities.

___________
Numerals in square brackets refer to the Bibliography.
---------------------- Page: 13 ----------------------
SIST EN 61788-15:2012
– 8 – 61788-15  IEC:2011
(IEC 60050-815:2000, 815-04-62)
3.2 General concepts
3.2.1 Intrinsic surface impedance

In general, the surface impedance Z of conductors, including superconductors, is defined as

the ratio of the tangential component of the electric field (E ) and that of the magnetic field (H )

t t
at a conductor surface:
Z = = R + jX . (1)
S S S

Here R denotes the surface resistance and X , the surface reactance. If the thickness of the

S S

conductor (or the superconductor) under test is sufficiently greater than the penetration depth

of electromagnetic fields, Z is expressed by
1 1
2 2
µ  jµω
Z = = (2)
   
ε σ
 
 

with ε and µ denoting the permittivity and the permeability of the conductor (or the

µ , the permeability of vacuum, σ, the conductivity
superconductor) under test, respectively,

of the conductor (or the superconductor), and ω, the measured angular frequency, and is

called the intrinsic surface impedance. σ is real for the conductor and complex for the

superconductor.
3.2.2 Effective surface impedance

If the thickness of the conductor (or the superconductor) under test is not sufficiently greater

than the penetration depth of electromagnetic fields, Z as defined by Equation (1) in 3.2.1

becomes significantly different from that defined by Equation (2) in 3.2.1. In this case, Z as

defined by Equation (1) is called the effective surface impedance Z with
Z = = R + jX (3)
Se Se Se

Here R denotes the effective surface resistance and X , the effective surface reactance.

Se Se
4 Requirements

The Z of HTS films shall be measured by applying a microwave signal to a dielectric

resonator with the superconductor specimen and then measuring the attenuation of the

resonator at each frequency. The frequency shall be swept around the resonant frequency as

the centre, and the attenuation-frequency characteristics shall be recorded to obtain the

Q-value, which corresponds to the loss.

The target relative uncertainty of this method is less than 10 % at temperatures of 30 K to

80 K.

It is the responsibility of the user of this standard to consult and establish safety and health

practices and to determine the applicability of regulatory limitations prior to use.

Hazards exist in this type of measurement. The use of a cryogenic system is essential to cool

the superconductors to allow transition into the superconducting state. Direct contact of skin

with cold apparatus components can cause immediate freezing, as can direct contact with a

spilled cryogen. The use of an r.f.-generator is also essential to measure high-frequency

---------------------- Page: 14 ----------------------
SIST EN 61788-15:2012
61788-15  IEC:2011 – 9 –

properties of materials. If its power is too high, direct exposure to human bodies can cause an

immediate burn.
5 Apparatus
5.1 Measurement equipment
Figure 1 shows a schematic diagram of the equipment required for the microwave

measurement. The equipment consists of a network analyzer system for transmission

measurements, a measurement apparatus, and thermometers for monitoring the temperature

of HTS films under test.

An incident power generated from a suitable microwave source such as a synthesized

sweeper is applied to the dielectric resonator fixed in the measurement apparatus. The

transmission characteristics are shown on the display of the network analyzer.
The measurement apparatus i
...

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