SSUPERKONDUKTORUPERKONDUKTOR

SSUHU UHU TTINGGIINGGI

Prof Dr Roslan Abd ShukorFakulti Sains & Teknologi

Universiti Kebangsaan Malaysiaras@ukm.my

Ciri-ciri SuperkonduktorCiri-ciri Superkonduktor

(i) Rintangan sifa(i) Rintangan sifar r (R = 0) (R = 0)- arus elektrik boleh mengalir tanpa sebarang rintangan.

(ii) Diamagnet sempurna (B(ii) Diamagnet sempurna (Bdalamdalam = 0) = 0)- tiada medan magnet - tiada medan magnet dalam bahan dalam bahan

Nobel Prize in Physics for Superconductivity (www.nobel.se)

__________________________________________________________________ Year Scientists Contributions to Superconductivity __________________________________________________________________

1913 H. K. Onnes Properties of materials at low temperature

1972 J. Bardeen, Microscopic (BCS) theory of conventional L. Cooper, and superconductorsR. Schrieffer

1973 I. Giaever and Tunnelling effects in superconductorB. Josephson

1986 J. G. Bednorz and Discovery of the copper oxide based highK.A. Müller temperature superconductor

1991 P. de Gennes Studies on complex systems (including superconductivity)

2003 V.L. Ginzburg Pioneering contributions to the theory of A.A. Abrikosov superconductivity

_______________________________________________________________________

Nobel Prize 2003"for pioneering contributions to the theory of superconductors and superfluids"

Alexei A. Abrikosov Vitaly L. Ginzburg Anthony J. Leggett

Pasaran DuniaPasaran Dunia

Menjelang tahun 2020 pasaran dunia berasaskan superkonduktor dianggarkan

bernilai

US$ 150 billion

• Latar belakangLatar belakang

• KegunaanKegunaan

• TeoriTeori

PembentanganPembentangan

Latar BelakangLatar Belakang

Pada tahun 1911 Heike Kamerlingh Onnes dari Belanda telah menemui superkonduktor pertama iaitu merkuri pada suhu 4.2 K (Hadiah Nobel 1913)

Teori superkonduktor konvensional (logam dan aloi) telah dikemukakan oleh Bardeen-Cooper-Schrieffer pada tahun 1957 (Hadiah Nobel 1972)

Pada tahun 1986

dua ahli sains dari makmal IBM di Switzerland, Bednorz dan Müller menemui bahan seramik berasaskan kuprum oksida yang mensuperkonduksi pada suhu yang lebih tinggi

0

30

60

90

120

150

180

1920 1940 1960 1980 2000

Tc

(K)

Year

MgB2

Hg-Ba-Ca-Cu-O (164 K, High Pressure)

Hg-Ba-Ca-Cu-O (134 K)

Tl-Ba-Ca-Cu-O (125 K)

Bi-Sr-Ca-Cu-O (110 K)

Y-Ba-Cu-O (90 K)Y-Ba-Cu-O (90 K)Y-Ba-Cu-O (90 K)

La-Sr-Cu-O (51 K, High Pressure)

La-Sr-Cu-O (35 K)

La-Ba-Cu-O (18 K)

Hg

Nb3Sn

Nb-Al-GeNbN

Nb3Sn

V3Si

NbPb

NbC

Liquid nitrogen (77 K)

Liquid helium (4.2 K)

Bahan SuperkonduktorBahan Superkonduktor

• Superkonduktor konvensional, logam dan aloi seperti Al, Pb, Nb3Sn, NbTi; suhu genting sehingga 23 K

• Fermion Berat seperti CeCu2Si2, UBe13 suhu genting < 1 K

• Asas kuprum oksida seperti HgBa2Ca3Cu4O11- suhu genting sehingga 134 K

• Borokarbida dan Boronitrida seperti LuNi2B2C dan La3Ni2B2N3 ; suhu genting < 20 K

• Organik seperti K3C60 ; suhu genting < 43 K

Ultraviolet 220 nm

(Huffman, 1977)

Astronomi 1960-an

Karbon 60 (CKarbon 60 (C6060)) Hablur CHablur C6060

Logam alkali

October 2005October 2005Nature Physics

Crystal structureof C6Ca. The unit cell isrhombohedral with the calciumatoms in green and graphenesheet in red.

Superkonduktor Superkonduktor Suhu Tinggi (SST)Suhu Tinggi (SST)

La-Sr-Cu-O Tc 35 K(Bednorz & Muller, 1986, Switzerland)

Y-Ba-Cu-O Tc 90 K(C.W. Chu et al, 1987, Houston)

Bi-Sr-Ca-Cu-O Tc 110 K (Maeda & Tanaka, 1988, Tokyo)

Tl-Ba-Ca-Cu-O Tc 125 K (Sheng & Hermann, 1988, Arkansas)

Hg-Ba-Ca-Cu-O Tc 134 K(Schilling,1993, Switzerland)

Satah CuO2

Sistem 2-dimensi

CuO

Y

Ba

March 2001March 2001

KegunaanKegunaanSuperkonduktorSuperkonduktor

Industri Kuasa - motor - generator - penyimpan tenaga - transmisi - transformer dan - induktor

KABEL TRANSMISI TENAGA

(ii) Extrusion Deformation into a mono-filamentary wire

(i) Mono-filamentary Billet

(iv) Multifilamentary bundling A number of mono-filamentary wires formed from individual billets are bundled together.

HTSC wires & tapes fabricationHTSC wires & tapes fabrication

(iii) Rolling of wires.The resulting multi-filamentary wires are then deformed into HTS tape.

A

B

CD

A-B

Ag

Bi2212

C-D

SEM of Ag Sheath Bi2212 High Temperature

Superconductor Tapes

Nasri & Abd-Shukor, 2001. Supercond. Sci. & Technol. (UK)

An HTS power cable is a wire-based device that carries large amounts of electrical current. Warm Dielectric CableThe warm dielectric cable configuration features a conductor made from HTS wires wound around a flexible hollow core. Liquid nitrogen flows through the core, cooling the HTS wire to the zero resistance state. The conductor is surrounded by conventional dielectric insulation. The efficiency of this design reduces losses.

HTS Transmission Cables

Superconductor Superconductor TransformersTransformers• Converts power from one voltage level to another.

• Significant energy losses occur in conventional transformers due to the iron in the core and the copper in the windings. An HTS transformer replaces the copper wire coils with lower loss.

• Small, quiet, lightweight and efficient HTS transformers can be used at substations within utility grid.

HTSC Fault HTSC Fault current limitercurrent limiter

The current limitation is based on the quench of a superconductor due to a current exceeding its critical current, resulting in a tremendous increase of its electrical resistance.

Superconductorin coolant bath

Superconducting Magnetic Superconducting Magnetic Energy Storage (SMES)Energy Storage (SMES)

221 LIE =

A Superconducting Magnetic Energy Storage (SMES) system, consists of superconductor coils. Energy stored within the coil can release megawatts of power within a fraction of a cycle to replace a sudden loss in line power

ElektronikElektronik

• Peranti Simpang Josephson • Pengesan Sinaran • Komunikasi• SQUID

R Kecil

R Besar

Q=1R

LC

LR=Δω

Pengangkutan Pengangkutan

M A G L E VM A G L E V

• Pengimbas dengan kontras tisu lembut yang tinggi

• Kini terdapat 6000 unit MRI di seluruh dunia

Pengimejan Pengimejan Resonans Resonans

Magnet (MRI)Magnet (MRI)

foton ()

rf

proton

PERUBATANPERUBATAN

Superconducting Quantum Interference Device (SQUID)

Mengesan perubahan kecil medan magnet

JT

Ja

Jb

Insulator a

Insulator b

B

Improved Call Quality

•The filtering of radio frequency (RF) energy represents an excellent application of superconductors because they can be used to achieve what no other technology has ever been capable of: producing the veritable “brick wall” filter that can reject unwanted signals while allowing desired signals to pass unimpeded through the filter.

Preselector filter located in the cell site building between the antenna and the base station receiver preamplifier.

Small R

Large R

Q=1R

LC

LR=Δω

CommunicationsCommunications

Beberapa Perkembangan BaruBeberapa Perkembangan Baru

(i) SST merupakan bahan dengan gelombang-diaitu pergerakan pasangan cas adalah anisotropik. Ini memungkinkan peranti baru untuk biomagnet direkabentuk.

(ii) Konsep pemisahan spin dan cas bagi model elektron - dijangka membina sistem elektronik yang baru

(Anderson et al. 1987, 2000).

elektron atau lohong

spinon (spin )

holon (cas Q)

Elektron Ion

MEKANISME SUPERKONDUKTORMEKANISME SUPERKONDUKTOR

mcT

mk

1~

=ωkBTc = 1.14 ωDe-1/

Teori Bardeen-Cooper-Schrieffer (BCS) Tc < 23 K

-

Spin- magnetic property

Charge- electronic property

ProtonConsists of quarks

The Atom

Electrons attracted to each other by interaction with lattice vibration

An electron distorts a lattice Produce a high charge density

A second electron attractedto the area

Superkonduktor Suhu Tinggi Di AngkasaSuperkonduktor Suhu Tinggi Di Angkasa

Launched by NASA in California, USA, 23 Feb 1999

Superconductor

Glassy CarbonS

U

N

S

A

T

Flight Module

Lab Module

Low Earth OrbitLEO < 1000 km

Geo Synch. Sat. 36,000 km

-40

-20

0

20

40

300

350

400

450

500

550

4000 8000 1.2 104 1.6 104 2 104

Temperature (C)

Resistance of YBCO (Ohm)

Time (s)

UTC: 927203883May 20, 1999 GMT: 12:38:03

Resistance of YBCO (Superconductor)

Mazlan Othman, Roslan Abd-Shukor, Hasan Adli Alwi, Mohamad Deraman& Ahmad Zaharim

OCu

Crystal structureYBa2Cu3O7-

+12V unregulated

Temperature sensor

1.2 k

2N3819

+

_

LM124J

+5V regulated

+

_

LM124J

100

3.9k

3.9k

1k

1k

A

B

+5V regulated

0.6

0.8

1

1.2

1.4

1.6

0 50 100 150 200 250 300

Time (minutes)

Io (mA)

-30

-10

10

30

50

70

Temperature (C)

(a)

(b)

(c)

The circuit diagram of the experimental module. The platinum resistor temperature sensor measures the external temperature of the satellite.

The variation of (a) average current (Io), (b) internal temperature (bold line), and (c) external temperature, with time on June 7th 1999.

S U P E R K O N D U K T O RS U P E R K O N D U K T O R

V I S I M A S A H A D A P A NV I S I M A S A H A D A P A N

Einstein’s House112 Mercer Street, Princeton, New Jersey