Cyclotron Resonance

We report on theoretical studies of a recently discovered strong microwave-induced magnetoresistance peak obtained in ultra-clean two-dimensional electron systems at low temperatures. The most striking feature of such a peak is that it shows up on the second harmonic of the cyclotron resonance and with an amplitude that can reach an order of magnitude larger than the microwave-induced resistance oscillations. We apply the microwave-driven electron orbits model in the ultra-clean scenario. Accordingly, we calculate the elastic scattering rate (charged impurity) which will define the unexpected resonance peak position. We also obtain the inelastic scattering rate (phonon damping), that will be responsible of the large peak amplitude. Calculated results are in good agreement with experiments. These results would be of special interest in nanophotonics; they could lead to the design of novel ultrasensitive microwave detectors.

... An attractive feature of the ICL is that the beam raises the dielectric constant of the ionchannel relative to its value outside the channel, and thus provides guiding of the ICL radiation. ... Wave guiding by the ion channel is also an interesting effect. ...

Abstract—A fundamental model consisting of charged particles moving in free space exposed to alternating and direct current (AC-DC) electromagnetic fields is analyzed. Effects of charged particles initial position and initial velocity to cyclotron resonance frequency are observed. ...

We present results of a detailed far-infrared magneto-optical study on a series of high-mobility InAs/Alx Ga1-x Sb (x=1.0, 0.8, 0.5, 0.4, 0.2, and 0.1) type-II single quantum wells. A wide range of phenomena arising from the unusual properties of two-dimensional (2D) electrons and holes and their Coulomb interaction in high magnetic fields has been revealed. Semiconducting samples (x>=0.4), in which only 2D electrons exist in the InAs wells, exhibit cyclotron-resonance (CR) splittings due to large conduction-band nonparabolicity. Semimetallic samples (x=0.1 and 0.2), in which both 2D electrons (in InAs) and 2D holes (in Alx Ga1-x Sb) are present, show two additional lines (e and h-X lines) as well as electron and hole CR. The X-lines increase in intensity at the expense of CR with increasing electron-hole (e-h) pair density, decreasing temperature, or increasing magnetic field (at low field), suggesting that they are associated with e-h binding which is increased by the magnetic ...

Following an overview of the ITER Ion Cyclotron Resonance Frequency (ICRF) system, the JET ITER‐like antenna (ILA) will be described. The ILA was designed to test the following ITER issues: (a) reliable operation at power densities of order at voltages up to 45 kV using a ...

The availability of a broad spectrum of highly enriched stable isotopes is vitally important for the fabrication of nuclear targets for basic and applied research. The present separation effort at the Oak Ridge National Laboratory is insufficient to maintain equilibrium for the stable isotope inventory. The current technology that is being applied in the electromagnetic isotope separation process to minimize the stable isotope depletion rate is discussed. Three alternative separation processes, gas centrifugation, plasma cyclotron resonance separation, and laser separation, are evaluated as candidates to augment the present stable isotopes separation facility. The applicability of each process to the isotopic enrichment of the calutron feed material and to the selective production of isotopes is determined. The process energy demands are compared to those of the existing facilities. The isotopic enrichment of the feed material prior to a first pass through the calutrons can result i...

Electron-electron interactions give rise to the correction, \delta\sigma^{int}(\omega), to the ac magnetoconductivity, \sigma(\omega), of a clean 2D electron gas that is periodic in \omega_c^{-1}, where \omega_c is the cyclotron frequency. Unlike conventional harmonics of the cyclotron resonance, which are periodic with \omega, this correction is periodic with \omega^{3/2}. Oscillations in \delta\sigma^{int}(\omega) develop at low magnetic fields, \omega_c\ll\omega, when the conventional harmonics are suppressed by the disorder. Their origin is a {\em double} backscattering of an electron from the impurity-induced Friedel oscillations. During the time \sim\omega^{-1} between the two backscattering events the electron travels only a {\em small portion} of the Larmour circle.

Results of experiments performed at the Institute for Space Research (INPE) are reported. An enrichment of 390 percent of carbon isotopes was achieved in the plasma centrifuge. The role of ion-acoustic turbulence in the formation of double layers was experimentally investigated. The turbulent spectrum was measured and agrees quite well with the prediction of the modified Kadomtsev renormalized theory. The

Laser mechanisms in the p-Ge far IR laser are identified and models presented to make laser line assignments in the three laser spectral regions: (A) multiple frequencies non-tunable with E and B, (B) multiple frequencies tunable with B, and (CR) single cyclotron frequencies tunable with B. Brief reviews of the classical and quantum theories of the p-Ge laser are given to support and explain the laser models.

Plasmas for thermonuclear fusion contain a highly non-thermal population of fast ions which may carry about one third of the plasma kinetic energy. Ions are accelerated to high energies by neutral beam injection or ion cyclotron resonance heating. They are also born in the deuterium-tritium fusion reaction which is the workhorse of c–particle heating for reactors