Woodstock Plus 20:High-Tc Today and Tomorrow

Paul M. Grant

IBM Research Staff Member, Emeritus

Press Conference2007 APS March Meeting

3:00 PM – 5:00 PMMonday, 5 March, CCC Room 208

Denver, Colorado

http://www.w2agz.com/woodstock07.htm

Fathers of Cryogenics

Dewar Kammerlingh-Onnes

CH4 112 KO 90N2 77Ne 27H2 20He 4.2

Thus the mercury at 4.2 K has entered a new state, which, owing to its particular electrical properties, can be called the state of superconductivity

H. Kamerlingh-Onnes (1911)

1911A Big Surprise!

TC vs. Year:1911 - 1980

Year

0

5

10

15

20

25

1900 1910 1920 1930 1940 1950 1960 1970 1980

Te

mp

era

ture

(K

)

Hg

Pb

NbN V3Si

Nb3Sn

Nb3Ge

Cubic Metals

MRI & “Big Physics”

Magnetic Resonance ImagingPhilips

TevatronFermi National Laboratory

Brookhaven Cable-Late 70s

1986Another Big Surprise!

Bednorz and MuellerIBM Zuerich, 1986

Onset TC = 40 K !

Physicists’ Night Out!Physicists’ Night Out!

“The Great Communicator”

HTSC Today

1980 2000

Hig

h-T

C

164 K

La-214

Hg-1223

V3Si

1900 1920 1940 1960

0

50

100

150

200T

emp

erat

ure

, T

C (K

)

Year

Low-TCHg

Practical HTSC Wire is Available

Oxide Powder1.Powder

Preparation

A. ExtrusionB. Wire Draw

C. RollingDeformation& Processing

3.

Oxidation -Heat Treat

4.

Billet Packing& Sealing

2.

Gen 1

Gen 2

Woodstock + 20Where are we?

• There remains no (generally accepted) theory to explain high-Tc

• Nonetheless, there exists now a high performance wire technology that works and is available in long lengths

• Yet no HTSC company is making a profit

…and old technology can go on and on and on…

IBM 305 Ramac

1956

The First Hard Drive

5 Megabytes

…51 Years Later

2007The Apple iPod

80 GB------------------------16000 times the Ramac in your

hand

“You can’t always get what you

want…”

“…you get what you need!”