Kamakhya Prasad Ghatak

In recent years, with the advent of fine line lithographical methods, molecular beam epitaxy, organometallic vapour phase epitaxy and other experimental techniques, low dimensional structures having quantum confinement in one, two and three dimensions (such as ultrathin films, inversion layers, accumulation layers, quantum well superlattices, quantum well wires, quantum wires superlattices, magneto-size quantizations, and quantum dots) have attracted much attention not only for their potential in uncovering new phenomena in nanoscience and technology, but also for their interesting applications in the areas of quantum effect devices. In ultrathin films, the restriction of the motion of the carriers in the direction normal to the film leads to the quantum size effect and such systems find extensive applications in quantum well lasers, field effect transistors, high speed digital networks and also in other quantum effect devices. In quantum well wires, the carriers are quantized in two transverse directions and only one-dimensional motion of the carriers is allowed.

In recent years, with the advent of ?ne line lithographical methods, molecular beam epitaxy, organometallic vapour phase epitaxy and other experimental techniques, low dimensional structures having quantum con?nement in one, two and three dimensions (such as inversion layers, ultrathin ?lms, nipi's, quantum well superlattices, quantum wires, quantum wire superlattices, and quantum dots together with quantum con?ned structures aided by various other ?elds) have attracted much attention, not only for their potential in uncovering new phenomena in nanoscience, but also for their interesting applications in the realm of quantum e?ect devices. In ultrathin ?lms, due to the reduction of symmetry in the wave-vector space, the motion of the carriers in the direction normal to the ?lm becomes quantized leading to the quantum size e?ect. Such systems ?nd extensive applications in quantum well lasers, ?eld e?ect transistors, high speed digital networks and also in other low dimensional systems. In quantum wires, the carriers are quantized in two transverse directions and only one-dimensional motion of the carriers is allowed. The transport properties of charge carriers in quantum wires, which may be studied by utilizing the similarities with optical and microwave waveguides, are currently being investigated. Knowledge regarding these quantized structures may be gained from original research contributions in scienti?c journals, proceedings of international conferences and various - view articles.

The merging of the concept of introduction of asymmetry of the wave vector space of the charge carriers in semiconductors with the modern techniques of fabric- ing nanostructured materials such as MBE, MOCVD, and FLL in one, two, and three dimensions (such as ultrathin ?lms, nipi structures, inversion and accumu- tion layers, quantum well superlattices, carbon nanotubes, quantum wires, quantum wire superlattices, quantumdots, magnetoinversionand accumulationlayers, qu- tum dot superlattices, etc. ) spawns not only useful quantum effect devices but also unearth new concepts in the realm of nanostructured materials science and related disciplines. It is worth remaking that these semiconductor nanostructures occupy a paramount position in the entire arena of low-dimensional science and technology by their own right and ?nd extensive applications in quantum registers, resonant tunneling diodes and transistors, quantum switches, quantum sensors, quantum logic gates, heterojunction ?eld-effect, quantum well and quantum wire trans- tors, high-speed digital networks, high-frequency microwave circuits, quantum cascade lasers, high-resolution terahertz spectroscopy, superlattice photo-oscillator, advanced integrated circuits, superlattice photocathodes, thermoelectric devices, superlattice coolers, thin ? lm transistors, intermediate-band solar cells, micro- tical systems, high-performanceinfrared imaging systems, bandpass ?lters, thermal sensors, optical modulators, optical switching systems, single electron/molecule electronics, nanotube based diodes, and other nanoelectronic devices.

In recent years, with the advent of fine line lithographical methods, molecular beam epitaxy, organometallic vapour phase epitaxy and other experimental techniques, low dimensional structures having quantum confinement in one, two and three dimensions (such as ultrathin films, inversion layers, accumulation layers, quantum well superlattices, quantum well wires, quantum wires superlattices, magneto-size quantizations, and quantum dots) have attracted much attention not only for their potential in uncovering new phenomena in nanoscience and technology, but also for their interesting applications in the areas of quantum effect devices. In ultrathin films, the restriction of the motion of the carriers in the direction normal to the film leads to the quantum size effect and such systems find extensive applications in quantum well lasers, field effect transistors, high speed digital networks and also in other quantum effect devices. In quantum well wires, the carriers are quantized in two transverse directions and only one-dimensional motion of the carriers is allowed.

In recent years, with the advent of ?ne line lithographical methods, molecular beam epitaxy, organometallic vapour phase epitaxy and other experimental techniques, low dimensional structures having quantum con?nement in one, two and three dimensions (such as inversion layers, ultrathin ?lms, nipi's, quantum well superlattices, quantum wires, quantum wire superlattices, and quantum dots together with quantum con?ned structures aided by various other ?elds) have attracted much attention, not only for their potential in uncovering new phenomena in nanoscience, but also for their interesting applications in the realm of quantum e?ect devices. In ultrathin ?lms, due to the reduction of symmetry in the wave-vector space, the motion of the carriers in the direction normal to the ?lm becomes quantized leading to the quantum size e?ect. Such systems ?nd extensive applications in quantum well lasers, ?eld e?ect transistors, high speed digital networks and also in other low dimensional systems. In quantum wires, the carriers are quantized in two transverse directions and only one-dimensional motion of the carriers is allowed. The transport properties of charge carriers in quantum wires, which may be studied by utilizing the similarities with optical and microwave waveguides, are currently being investigated. Knowledge regarding these quantized structures may be gained from original research contributions in scienti?c journals, proceedings of international conferences and various - view articles.