Flinders University of South AustraliaFlinders University of South AustraliaLeon MitchellLeon MitchellNathan PriorNathan Prior

University of SydneyUniversity of SydneyBrian JamesBrian James

Alex SamarianAlex SamarianFelix CheungFelix Cheung

Flinders University of South AustraliaFlinders University of South AustraliaLeon MitchellLeon MitchellNathan PriorNathan Prior

University of SydneyUniversity of SydneyBrian JamesBrian James

Alex SamarianAlex SamarianFelix CheungFelix Cheung

XXXX____Program

Introduction

Experimental setup

Results and discussion on the rotation of various dust plasma crystal configurations:

Large

Small

Annular

Future research

Summary of experimental results

Conclusion

XXXX____What is a Dust Plasma Crystal?

A well ordered and stable array of highly negatively charged dust particles suspended in a plasma

Relatively new scientific field with many interesting properties discovered

Theoretical predictionIkezi (1986)

Experimental confirmationLin I et el (1994), Thomas H et el (1994)

Recent interests include:Dynamical behavior (oscillations, waves, convective motion)

Solid State (melting, crystal growth, structural packing)

XXXX____The Basic Ingredients

Melamine formaldehyde polymerSpherical, micron-sized and mono-dispersed

Electrons:Small, light and fast moving

Frequent collisions with particles

Ions:Big, heavy and slow moving

Minimal interaction with particles

Neutrals:Damping in system

Argon plasmaArgon plasma

Dust particlesDust particles

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GravitationGravitational Forceal Force

Electrostatic Electrostatic ForceForce

Dust Plasma Crystal Production

Produce an argon plasmaDisperse particles with shakerParticles will then:

Charge negativelyFall under gravityBalance at sheath-plasma interface

Mg = eZEs

Arrange to form crystal structure

XXXX____Experimental Setup

Observationwindow

Teflon rod

Shaker

RF coil

Viewing area

Quartz window

Turbo-molecular vacuum pump

Electrode and Electrode and coil on mountcoil on mount

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