Thermoelectric current in a graphene Cooper pair splitter.

Area of Science:

• Condensed Matter Physics
• Quantum Phenomena
• Materials Science

Background:

• The Seebeck effect, generating voltage from temperature gradients, is crucial for thermoelectric devices.
• Recent theories predict novel thermoelectric effects in hybrid superconductor-normal metal structures.
• Cooper pair splitting and co-tunneling are key quantum phenomena in such systems.

Purpose of the Study:

• To experimentally observe the non-local Seebeck effect in a graphene-based device.
• To provide a theoretical framework for the observed phenomenon.
• To explore the potential of this effect for generating entangled electrons.

Main Methods:

• Fabrication of a graphene device with two quantum dots connected to an aluminum superconductor.
• Application of a temperature gradient across the device.
• Measurement of the generated electric voltage.
• Development of a theoretical model to explain the observations.

Main Results:

• Successful observation of the non-local Seebeck effect in the graphene device.
• Experimental data aligns with the theoretical predictions.
• Demonstration of Cooper pair splitting and elastic co-tunneling contributing to the effect.

Conclusions:

• The non-local Seebeck effect is experimentally verified in a graphene Cooper pair splitting device.
• This phenomenon provides an efficient method for producing entangled electrons.
• The findings open new avenues for quantum information processing and spintronics.