1. (Graduation thesis at Nihon University)
Graduation thesis “ G-L theory and gauge symmetry breaking in superconductivity ” and Science school “ What is superconductivity ? ”
(Graduation thesis at Nihon University)
Noriaki Kobayashi
June 7th, 2006
Shibata lab.
CONTENTS
Introduction
What is superconductivity?
Ginzburg –Landau theory
Science school

2. macroscopic properties
Introduction
Theory of superconductivity
GL (Ginzburg-Landau )theory : explain macroscopic properties
BCS theory : explain microscopic mechanisms
Meissner effect , flux quantization , …
macroscopic properties
magnet
magnetic flux
magnetic flux
Superconductor
ring
superconductor
flux quantization
Meissner effect

3. What is superconductivity?
Superconductivity is a phenomenon occurring in certain materials
(superconductor) at low temperatures.
superconducting state
normal state
It is characterized by
zero electrical resistance
the exclusion of the magnetic flux
(the Meissner effect)
Electrical resistance [Ω] R Tc T
Temperature [K]
Hg ; Tc～ 4K

4. Ginzburg-Landau theory
Ginzburg and Landau thought :
complex order parameter
describes the superconducting state
Ginzburg – Landau equation
This equation explains macroscopic properties in superconductivity

5. Science school
I thought observing real phenomena is impotant. Therefore, I organized the science school at Tamarokuto science museum in may, 2006.
experiment of the Meissner effect

6. I will talk about the G-L theory , a gauge symmetry breaking in superconductivity,and the science school in poser session.