Skip to Main Content
 

Global Search Box

 
 
 
 

Files

File List


LazoM_Dissertation2014.pdf (11.22 MB)

ETD Abstract Container

Abstract Header

Liquid Crystal Enabled Electrokinetic Phenomena

Lazo-Martinez, Israel Esteban
http://rave.ohiolink.edu/etdc/view?acc_num=kent1397725003

Abstract Details

2014, PHD, Kent State University, College of Arts and Sciences / Chemical Physics.
Electrophoresis (EP) is a motion of charged dispersed particles relative to a fluid in a uniform electric field. The effect is widely used to separate macromolecules (e.g. DNA and proteins), to assemble colloidal structures, to transport particles in nano- and micro-fluidic devices and displays such as the KINDLE electronic paper and other electrophoretic or e-ink displays. Typically, the fluid is isotropic (for example, water) and the electrophoretic velocity of dispersed particles is directly proportional to the electric field. Because of this linear dependence, only a direct current (DC) electric field can be used to drive the particles through the fluid. However, the use of an alternating current (AC) electric field to drive the particles is more desirable, as it prevents electrolysis, i.e., electrochemical reactions near the electrodes resulting in degradation of the medium. Furthermore, the use of AC electric fields to drive the particles allows one to create steady flows, as the AC field avoids accumulation of the electric charges near the electrodes. In this dissertation we show that when the EP is performed in a nematic fluid, the effect becomes strongly non-linear with a velocity component that is quadratic in the applied voltage and has a direction that generally differs from the direction of linear velocity. We call this new phenomenon Liquid Crystal Enabled-Electrophoresis (LCEEP), the effect is caused by distortions of the LC orientation around the particle that break the fore-aft (or left-right) symmetry. The effect allows one to transport both charged and neutral particles, even when the particles themselves are perfectly symmetric (spherical), thus enabling new approaches in display technologies, colloidal assembly, separation, microfluidic and micromotor applications.
Oleg D. Lavrentovich, Prof. (Advisor)
102 p.
Physics
Liquid Crystal Enabled-Electrophoresis, Electro-osmosis, AC Nonlinear electrokinetics, Flow visualization

Recommended Citations

Citations

  • Lazo-Martinez, I. E. (2014). Liquid Crystal Enabled Electrokinetic Phenomena [Doctoral dissertation, Kent State University]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=kent1397725003

    APA Style (7th edition)

  • Lazo-Martinez, Israel. Liquid Crystal Enabled Electrokinetic Phenomena. 2014. Kent State University, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=kent1397725003.

    MLA Style (8th edition)

  • Lazo-Martinez, Israel. "Liquid Crystal Enabled Electrokinetic Phenomena." Doctoral dissertation, Kent State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=kent1397725003

    Chicago Manual of Style (17th edition)

kent1397725003
1,057
© 2014, all rights reserved.
This open access ETD is published by Kent State University and OhioLINK.