Related Experiment Video
Updated: Jul 18, 2026

Mechanical Manipulation of Neurons to Control Axonal Development
Published on: April 10, 2011
Calculations and measurements of wire and/or split-ring negative index media
F J Rachford1, D L Smith, P F Loschialpo
1Naval Research Laboratory, Washington, DC 20375, USA.
Abstract:
Broadband calculations (70 MHz-20 GHz) and measurements (2-15 GHz) were performed on planar stacks of two-dimensional double-split rings arrays interspersed with arrays of thin wires. Recent work on similar composite structures infers a negative index of refraction (n<0) over a narrow frequency range. We have performed finite-difference time-domain (FDTD) calculations on various combinations of ring geometries, wire arrays, and stack spacings. Excellent agreement was obtained between FDTD simulations and our measured transmission spectra. Examining the FDTD time progression of fields we find regions of both negative and positive indices as well as an inverse Doppler effect.
Related Concept Videos
Magnetic Force On Current-Carrying Wires: Example
Magnetic Field Due To A Thin Straight Wire
Toroids
When connected to a supply, the magnetic field generated in the toroid has field lines circular and concentric to its axis. Conventionally, the direction of this magnetic field is expressed using the right-hand rule. If the fingers of the right hand curl in the current direction, the thumb points in the...
Self-Inductance
Consider a circuit connected to an AC source. As the current varies with time, the magnetic flux through the circuit correspondingly changes. Faraday's law tells us that an emf would therefore...
Calculation of Self-inductance
Since the effect of the induced electric field and the back EMF generated depends on the rate of change of current and the self-inductance, the inductance...
Thermal expansion and Thermal stress: Problem Solving
To solve the problem, first, identify the known and unknown quantities. The initial length (L) of the bridge is 1275 m, the coefficient of linear expansion (α) for steel is 12 x 10-6/°C, and the change in temperature (ΔT) is 55 °C.

