The first realistically photon-like Schrödinger solution of Maxwell's classical equations in dispersive media is presented.
Classical modes of transverse electric or transverse magnetic fields with angular frequency ω propagating along an axis
are shown to be able to be enveloped with counter-rotating helical modulations which have a different angular frequency
Ω. These helical rotations, called distributed spin rotations, propagate at the group velocity. The formation of a
completely closed packet of electromagnetic energy requires that the axial fields and transverse fields have a common
axial length of envelope. This forces Ω to take quantized values in terms of ω with Ω related to the Schrödinger frequencies of a harmonic oscillator. The spin rotations permit flexible transverse confinement allowing for localization of the photon wave-packet over different spatial areas. It is argued that the energy of this packet is not related to its
volume but depends on the quantized helical frequency Ω. Such photon-like packets possess classical phase and group
velocities in keeping with experimental evidence. A single photon-like packet does not disperse in dispersive media.
Incrementing or decrementing the rate of helical rotation promotes or demotes the packet energy in keeping with
standard photon theory. The model offers explanations for self-interference and entanglement.
Understanding the nature of single-photon propagation and any differences to the classical multi-photon regime is essential to better use the escalating number of single-photon technologies. Novel techniques and results are reported that demonstrate a consistent ability to measure the classical group velocity in an optical fiber to an accuracy in the time-offlight around ±0.2 ns in 30,000 ns. Identical techniques are then applied to single photons to determine their velocity and assess if there is any evidence that Schrödinger frequencies (N+1/2)ω alter the ω-k dispersion diagram. The evidence suggests that photons in a circular fiber show no additional dispersion but travel at the classical group velocity.
The role of push-pull design in electronics is well known. In this paper this role is examined in connection with split contact DFB lasers. Two or three contacts combined with push-pull modulation permit the energy to be moved laterally back and forth in the laser without changing, while modulating the output. Links between changes in the stored energy and the dynamic chirp are examined showing that changes in the symmetry of the push-pull current drive allow one to tailor the chirp so as to minimize dispersion for a given structure and fiber. Push-pull operation changes the fundamental resonances that limit speed of modulation in the laser and in particular the classic photon-electron resonance is replaced with a structural dependent resonance. For a given gain in the laser it appears that push-pull operation offers higher modulation bit rates as well as the potential for controlled chirp. The intrinsic equivalent circuit for push-pull operation of a DFB is shown to have three poles and the design compromises for operation at 50 and 100 Gb/s are discussed briefly.
The pattern recognizing power of a double-layer hetero-associative neural network is discussed in some detail and demonstrated using a set of 256 Chinese characters. The results show that a pattern, unrecognizable to the human eye, can be recalled as being a corrupted version of a particular character from this set.