Superconducting quantum electronics

The quantum electronic properties of superconductors have been vividly demonstrated by means of experiments on Josephson tunneling junctions and small area superconducting contacts. Emphasis is placed on ring configurations where quantum state transitions corresponding to changes of magnetic flux of2.07 times 10^{15}webers are directly observed. Such systems can be used to make ultrasensitive measurements of magnetic fields, electric currents and voltages, cryogenic temperatures, and electro-magnetic radiation.     

New horizons in quantum electronics

In the broad sense the term ``quantum electronics' relates to the motion of electrons as governed by quantum mechanical laws, but used more specifically it refers to electronic processes involving transitions between discrete energy levels. The latter category includes the laser, and it is to this development, which is responsible for most of the new horizons in the field, that this article is primarily devoted. Two specific examples are described: a tunable light oscillator and an intense-light-pulse generator. It is pointed out that, despite their promise, the ultimate impact of the laser devices on industrial technology cannot be predicted.     

Photochromic materials for quantum electronics

The characteristics of idealized photochromic materials are defined. The optical properties of rare-earth-doped CaF2and transition-metal-doped SrTiO3photochromic materials are outlined. The operational parameters of these inorganic photochromic materials pertinent to electrooptic applications are described.     

Ideas and stumbling blocks in quantum electronics

Quantum electronics, including in particular the maser and the laser, represents a marriage between quantum physics and electrical engineering which was probably longer delayed than it might have been because the two were not sufficiently acquainted. The mutual discovery of one field by the other is discussed, as well as the misunderstandings and false starts. Specific examples are used to make more real the thinking of the early years in this field and the struggles with ideas which, as with most now-understood sciences or technologies, seem much simpler in retrospect.     

QHE key to spin electronics and quantum computing

Researchers Shuichi Murakami, University of Tokyo and Shoucheng Zhang, Stanford University may have discovered a spin current associated with holes rather than electrons in semiconductors. The predicted current would be able to inject spin momentum into quantum dots and would interact with conventional electron currents, bridging electronics and spin-based quantum circuits.Visit www.three-fives.com for the latest advanced semiconductor industry news     

Progress of quantum electronics and the future of wireless technologies

Research in quantum electronics over several decades has fueled the creation and rapid growth of today's wireless communications market. Sales of electronic components into this market exceeded $25 billion in 2006. Nearly all cellular handsets sold today include integrated circuits (ICs) based on energy gap engineered transistors—high-electron mobility transistors (HEMTs) and heterojunction base transistors (HBTs). The success of these technologies notwithstanding, future wireless communications systems will require even more demanding IC performance, especially in the areas of linearity and low noise. We propose that a new concept in transistor design, wave-function engineering, offers un-tapped opportunities to realize these needed performance improvements.