Experiments

1. Nuclear Magnetic Resonance (NMR) in liquids
2. Optical Pumping
3. Doppler-free Rb saturation spectroscopy
4. Electro- and Photoluminescence


5. Rotation-Vibration Spectra of Molecules
6. Lattice Vibrations and Effects of Free Charge Carriers in Solids
7. Raman-Spectroscopy on Solids


8. Zeeman Effect
9. High-Resolution Gamma-Spectroscopy with Ge-Semiconductor Detector
10. Alpha-Particle Spectroscopy with a Semiconductor Detector


11. X-Ray diffraction (XRD)
12. Mass Spectroscopy on Gases and simple Organic Molecules
13. Hall-Effect and Electrical Conductivity


14. Optical Spectroscopy at Colour Centers and Molecules
15. Franck-Hertz Experiment
16. Squid Experiment


17. Electron-Paramagnetic Resonance (EPR)
18. Study of Solid State Surfaces using a Scanning Tunnelling Microscope
19. Study of Solid State Surfaces using a Atomic Force Microscope

Flux quantization in superconducting rings: experiments with a DC-SQUID

Supervisor: M. Sc. D. Reinhardt

Superconductor have below a critical temperature (transition temperature) a negligible electrical resistance and allow so almost lossless current conduction. Superconductivity is a quantum mechanical state. Model descriptions based upon paired electrons (Cooper pairs), which obey the Bose-Einstein statistics.

Experiments are performed under the use of a DC SQUID (direct current - superconducting  Quantum interference device), consisting from a YBaCuO thin-film structure.

For this high temperature superconducting compound oxide is  the superconducting Critical temperature above 77 K and a cooling with liquid nitrogen is sufficient:

 

(a) Voltage-current measurements at a DC-SQUID, determination of the critical current,  determination of Resistance in the normal state, determining the characteristic Voltage.

(b) Shapiro-step measurement (V-I measurement with microwave coupling), determination  of the fundamental constant e / h from the measurements.

(c) Voltage-Flux Characterization, flux-locked loop measurements, determination of the  maximum voltage modulation of a flux quantum, flux quantization in  superconducting rings, to determine the relationship between output voltage  and the magnetic flux (SQUID as a highly sensitive magnetic field sensor).



sq1

description of this experiment
manual
components