230 likes | 609 Views
Aharonov-Casher Effect. Experimental Method. Making the Specimen. Yttrium Barium Copper Oxide (YBa 2 Cu 3 O 7- ). Making the Specimen. Crushing old YBCO specimens. Making the Specimen. Crushing old YBCO specimens Filling die with YBCO powder Add ethanol Compress in vice.
E N D
Aharonov-Casher Effect Experimental Method
Making the Specimen Yttrium Barium Copper Oxide (YBa2Cu3O7-)
Making the Specimen • Crushing old YBCO specimens
Making the Specimen • Crushing old YBCO specimens • Filling die with YBCO powder • Add ethanol • Compress in vice
Making the Specimen • Crushing old YBCO specimens • Filling die with YBCO powder • Add ethanol • Compress in vice • Sinter
Making the Specimen • Crushing old YBCO specimens • Filling die with YBCO powder • Add ethanol • Compress in vice • Sinter • Cut & Polish Specimen
Experiments Testing Superconductivity (AC Resistivity)
Experimental Setup Helium Fridge Specimen “Cold Finger”
Experimental Setup Ammeter Function Generator Computer Cathode Ray Oscilloscope Voltage Source Selectable Resistor (1kΩ) Lock-in Amplifier
Testing Circuit Diagram ACVoltage Lock-In Amp Voltage Sense Meter Current Sense Meter Thermocouple Specimen
Experiments Aharonov-Casher Effect
Experimental Setup Ramp Generator Ammeter Computer Cathode Ray Oscilloscope Voltage Source Selectable Resistor (1kΩ)
Circuit Diagram Voltage Ramp & 1000µF Capacitor LeCroy Oscilloscope DC Voltage & Resistor “Cold Finger”
Measuring The Effect • Charge “ramp” in centre • Causes frequency in V/A • Analysed by Fast Fourier Transform (FFT)
LeCroy Dual-Oscilloscope Real-time FFT Difference between Saved & average Averaged FFT Saved FFT
Possible Solutions • Noise-free environment • More accurate voltage ramp • Use thin film sample • Better capacitance calculation