Precision Measurement and Comprehensive Analysis of Dielectrophoretic Crossover Behavior of Micro-Particles

Abstract To be one of the hottest topics recent years, a huge amount of diverse applications of the Dielectrophoresis (DEP) phenomenon have been discovered and published. The DEP force mainly comes from the difference in dielectric polarizability between the suspended particles and the suspending medium and it only occurs when the applied AC electric field is non-uniform in space. There are many important parameters that affect the magnitude, direction and the crossover frequency of the DEP force, such as the applied AC electric field frequency, electric field distribution, applied voltage, medium conductivity, particle permittivity, particle size, the electric double layer of particles and so on. Variation of each of the above mentioned parameters could cause great difference in the dielectrophoretic behavior of particles. People have made great efforts in quantifying the influence of them but there are still a lot of uncertain relations and mechanisms to be verified. Therefore, we present a comprehensive analysis of the crossover behavior of micro-particles due to DEP and several concurrent phenomena through both experiments and finite element simulations and provides an important foundation for further insight into electrical properties of micro-particles and for more advanced Lab-on-chip devices developments.

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Non-Linear Behavior of Electrothermal Flows

Volume 6: Fluids and Thermal Systems; Advances for Process Industries, Parts A and B ◽

10.1115/imece2011-62817 ◽

2011 ◽

Author(s):

Paul Kauffmann ◽

Sophie Loire ◽

Marin Sigurdson ◽

Igor Mezic´

Keyword(s):

Electric Field ◽

Scientific Community ◽

Particle Image ◽

Measured Data ◽

Lab On Chip ◽

Ac Electric Field ◽

Linear Behavior ◽

Electrokinetic Flows ◽

On Chip ◽

Buoyancy Flows

Recently, electrokinetic flows have raised the interest of scientific community. Driving flow with an electric field leads to promising applications for mixing, concentration and pumping application in lab on chip. However, current models are still inaccurate and in many cases dont fit the measured data. The work presented here is mainly focused on AC electrothermal flows (ACET) carried out in microwells. An AC electric field is applied between 3 interdigitated gold electrodes. Using μPIV (μ Particle Image Velocity) vortex flows are characterized. The competition between light induced (LEF), AC induced electrothermal (ACET) and buoyancy flows (BF) is discussed. Based on those experimental observations, a new theory is tackled. It takes into account the observed instability like behaviour and the discrepancy of the voltage influence on velocities at high conductivity.

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Detailed discussion of a linear electric field frequency shift induced in confined gases by a magnetic field gradient: Implications for neutron electric-dipole-moment experiments

Physical Review A ◽

10.1103/physreva.71.032104 ◽

2005 ◽

Vol 71 (3) ◽

Cited By ~ 44

Author(s):

S. K. Lamoreaux ◽

R. Golub

Keyword(s):

Magnetic Field ◽

Dipole Moment ◽

Electric Field ◽

Frequency Shift ◽

Electric Dipole Moment ◽

Electric Dipole ◽

Magnetic Field Gradient ◽

Neutron Electric Dipole Moment ◽

Field Frequency ◽

Electric Field Frequency

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Modified Morris-Lecar neuron model: Effects of very low frequency electric fields and of magnetic fields on the local and network dynamics of an excitable media

10.21203/rs.3.rs-170503/v1 ◽

2021 ◽

Author(s):

Karthikeyan Rajagopal ◽

Irene Moroz ◽

Balamurali Ramakrishnan ◽

Anitha Karthikeyan ◽

Prakash Duraisamy

Keyword(s):

Magnetic Field ◽

Magnetic Fields ◽

Electric Field ◽

Neuron Model ◽

Low Noise ◽

Spiral Waves ◽

Excitable Media ◽

Field Frequency ◽

Electric And Magnetic Fields ◽

Electric Field Frequency

Abstract A Morris-Lecar neuron model is considered with Electric and Magnetic field effects where the electric field is a time varying sinusoid and magnetic field is simulated using an exponential flux memristor. We have shown that the exposure to electric and magnetic fields have significant effects on the neurons and have exhibited complex oscillations. The neurons exhibit a frequency-locked state for the periodic electric field and different ratios of frequency locked states with respect to the electric field frequency is also presented. To show the impact of the electric and magnetic fields on network of neurons, we have constructed different types of network and have shown the network wave propagation phenomenon. Interestingly the nodes exposed to both electric and magnetic fields exhibit more stable spiral waves compared to the nodes exhibited only to the magnetic fields. Also, when the number of layers are increased the range of electric field frequency for which the layers exhibit spiral waves also increase. Finally the noise effects on the field affected neuron network are discussed and multilayer networks supress spiral waves for a very low noise variance compared against the single layer network.

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