Superfluid Helium-4 Transition on Multi-walled

Carbon NanotubesPresenter: Vito Iaia

Principal Investigator: Dr. Gary WilliamsMentor: Emin Menachekanian

Department: Physics and Astronomy4/23/15

What is Superfluid Helium-4 ?Quantum fluid (below Tλ = 2.17

K)No viscosity No entropy

Macroscopic Bose-CoherenceAdsorbes on top of substratesTransition temperature changes

with thinner films

Helium film adsorbed on

surface

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What do we Measure?3

Main Superfluid setupMixing Chamber

Cell

ShakerCooling

Capabilities Limited

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Influence of Shaker (225Hz) 5

Experimental Approach6

Source: W. Robertson , B. Cazzolato and A. Zander, IEEE TRANSACTIONS ON MAGNETICS, 48, No. 9, 2012.

Results (225Hz)

Similar results to original setup

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Conclusions

New setup produces same response as old setupMore uniform vibration across the setupPotential for less energy load on mixing chamber

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Future Directions

Investigate Thinner Films

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4 5 6

Future DirectionsPotential Quantum Phase

Transition

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Thanks!Thanks to Dr. Gary WilliamsGraduate mentor: Emin Menachekanian Williams lab: Bob Chen, Andrew Li, Sergey

Sushchikh UC LEADS Questions?

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