There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

The term photonic crystals appears because of the analogy between electron waves in crystals and the light waves in artificial periodic dielectric structures. During the recent years the investigation of one-, two-and three-dimensional periodic structures has attracted a widespread attention of the world optics community because of great potentiality of such structures in advanced applied optical fields. The interest in periodic structures has been stimulated by the fast development of semiconductor technology that now allows the fabrication of artificial structures, whose period is comparable with the wavelength of light in the visible and infrared ranges.

http://ieeexplore.ieee.org/iel5/6354/16969/00781867.pdf

Photonic crystals

In this chapter, we will restrict our attention to the ferrites and a few other closely related materials. The great interest in ferrites stems from their unique combination of a spontaneous magnetization and a high electrical resistivity. The observed magnetization results from the difference in the magnetizations of two non-equivalent sub-lattices of the magnetic ions in the crystal structure. Materials of this type should strictly be designated as “ferrimagnetic” and in some respects are more closely related to anti-ferromagnetic substances than they are to ferromagnetics in which the magnetization results from the parallel alignment of all the magnetic moments present. We shall not adhere to this special nomenclature except to emphasize effects, which are due to the existence of the sub-lattices.

Ferromagnetic materials

3d-transition-metal-doped ZnO films (n-type Zn1−xMxO (x=005–025): M=Co, Mn, Cr, Ni) are formed on sapphire substrates using a pulsed-laser deposition technique, and their magnetic and electric properties are examined The Co-doped ZnO films showed the maximum solubility limit Some of the Co-doped ZnO films exhibit ferromagnetic behaviors with the Curie temperature higher than room temperature The magnetic properties of Co-doped ZnO films depend on the concentration of Co ions and carriers

Magnetic and electric properties of transition-metal-doped ZnO films

Recent advances in the theory and experimental realization of ferromagnetic semiconductors give hope that a new generation of microelectronic devices based on the spin degree of freedom of the electron can be developed. This review focuses primarily on promising candidate materials (such as GaN, GaP and ZnO) in which there is already a technology base and a fairly good understanding of the basic electrical and optical properties. The introduction of Mn into these and other materials under the right conditions is found to produce ferromagnetism near or above room temperature. There are a number of other potential dopant ions that could be employed (such as Fe, Ni, Co, Cr) as suggested by theory [see, for example, Sato and Katayama-Yoshida, Jpn. J. Appl. Phys., Part 2 39, L555 (2000)]. Growth of these ferromagnetic materials by thin film techniques, such as molecular beam epitaxy or pulsed laser deposition, provides excellent control of the dopant concentration and the ability to grow single-phase layers. T...

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Wide band gap ferromagnetic semiconductors and oxides

Previously published studies of a new dispersion relation in optical rotary dispersion (ORD) from refractometry have been extended to the ultraviolet (UV) region. The results from studies made of bovine serum albumin and insulin in the UV region are presented. The results confirm the abnormal behavior of ORD in the UV and suggest a new way to use refractive index data in the UV to study other phenomena. >

http://ieeexplore.ieee.org/iel2/846/3080/00096427.pdf

ORD of BSA and insulin in UV region by new dispersion relation

Isostructural phase transition (IPT) in CaMoO4 with Scheelite structure

Studies in magnetooptic rotatory dispersion (MORD) involve expensive instrumentation, which many laboratories in developing countries cannot afford. A low-cost instrument based on the principle of a novel dispersion relation is developed, and its usefulness is tested for a few secondary alcohols and synthetic polymers. The results are quite encouraging. >

An inexpensive alternative for the studies of MORD

Heteroaromatic studies of purine and a few of its derivatives such as adenine and guanine are discussed with special reference to the electrophilic and nucleophilic reactivity of the carbon atoms. The molecular vibration method and the quantum mechanical δ-function model are applied to obtain the bond polarizability values. The bond polarizability coefficients reveal the aliphatic or nucleophilic and aromatic or electrophilic nature of the carbon atoms present in the purine ring. The results are discussed in relation to X-ray diffraction studies, NMR chemical shifts and quantum chemical calculations. The good agreement suggests the applicability of the polarizability studies to the heteroaromatic studies.

V. R. K. Murthy

Papers

ORD of BSA and insulin in UV region by new dispersion relation

Isostructural phase transition (IPT) in CaMoO4 with Scheelite structure

An inexpensive alternative for the studies of MORD

Heteroaromatic Studies of Purine Bases

Structural, morphological and microwave dielectric studies on microwave sintered ZnWO4 ceramic compounds