Aharonov-Casher Effect

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Aharonov-Casher Effect

• Experimental Method

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Making the Specimen

• Yttrium Barium Copper Oxide
• (YBa2Cu3O7-?)

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Making the Specimen

• Crushing old YBCO specimens

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Making the Specimen

• Crushing old YBCO specimens
• Filling die with YBCO powder
• Add ethanol
• Compress in vice

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Making the Specimen

• Crushing old YBCO specimens
• Filling die with YBCO powder
• Add ethanol
• Compress in vice
• Sinter

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Making the Specimen

• Crushing old YBCO specimens
• Filling die with YBCO powder
• Add ethanol
• Compress in vice
• Sinter
• Cut Polish Specimen

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Finished Specimen
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Experiments

• Testing Superconductivity
• (AC Resistivity)

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Experimental Setup
Helium Fridge
Specimen Cold Finger
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Experimental Setup
Ammeter
Function Generator
Computer
Cathode Ray Oscilloscope
Voltage Source
Selectable Resistor (1k?)
Lock-in Amplifier
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Testing Circuit Diagram
AC Voltage
Lock-In Amp
Voltage Sense Meter
Current Sense Meter
Thermocouple
Specimen
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Results
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Experiments

• Aharonov-Casher Effect

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Experimental Setup
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Experimental Setup
Ammeter
Ramp Generator
Computer
Cathode Ray Oscilloscope
Voltage Source
Selectable Resistor (1k?)
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Circuit Diagram
Voltage Ramp 1000µF Capacitor
LeCroy Oscilloscope
DC Voltage Resistor
Cold Finger
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Measuring The Effect

• Charge ramp in centre
• Causes frequency in V/A
• Analysed by Fast Fourier Transform (FFT)

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Measuring The Effect
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LeCroy Dual-Oscilloscope
Real-time FFT
Difference between Saved average
Averaged FFT
Saved FFT
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Possible Solutions

• Noise-free environment
• More accurate voltage ramp
• Use thin film sample
• Better capacitance calculation