Journal ArticleDOI
Quantum well oscillators
TLDR
In this article, double barrier resonant tunneling structures have been used to increase the tunneling current density by a factor of nearly 100, with the attendant increase in gain and improved impedance match to the resonant circuit.Abstract:
Oscillations have been observed for the first time from double barrier resonant tunneling structures. By eliminating impurities from the wells, we have been able to increase the tunneling current density by a factor of nearly 100. With the attendant increase in gain and improved impedance match to the resonant circuit, the devices oscillated readily in the negative resistance region. Oscillator output power of 5 μW and frequencies up to 18 GHz have been achieved with a dc to rf efficiency of 2.4% at temperatures as high as 200 K. It is shown that higher frequencies and higher powers can be expected.read more
Citations
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Journal ArticleDOI
Quantum confinement and host/guest chemistry: probing a new dimension.
TL;DR: Current approaches for generating nanostructures of conducting materials are briefly reviewed, especially the use of three-dimensional crystalline superlattices as hosts for quantum-confined semiconductor atom arrays (such as quantum wires and dots) with controlled inter-quantum-structure tunneling.
Journal ArticleDOI
Resonant tunneling through double barriers, perpendicular quantum transport phenomena in superlattices, and their device applications
TL;DR: In this article, a simple expression for the low field mobility in the miniband conduction regime is derived; localization effects, hopping conduction, and effective mass filtering are discussed.
Journal ArticleDOI
Frequency limit of double‐barrier resonant‐tunneling oscillators
TL;DR: In this article, it was shown that the intrinsic RC delay of a single barrier limits the frequency of active oscillations to fmax = 1/(2πτ), where τ =eα−1(λ/c)exp(4πd/λ) with λ being the de Broglie wavelength of the tunneling electron, d the barrier thickness, e the dielectric permittivity, c the speed of light, and α≊1/137 the fine-structure constant.
Journal ArticleDOI
Band-Gap Engineering: From Physics and Materials to New Semiconductor Devices
TL;DR: A new generation of devices with unique capabilities, ranging from solid-state photomultipliers to resonant tunneling transistors, is emerging from this approach to band-gap engineering.
Journal ArticleDOI
A bird's-eye view on the evolution of semiconductor superlattices and quantum wells
TL;DR: In this paper, significant milestones are presented with emphasis on experimental investigations in the device physics of reduced dimensionality performed in cooperation with the materials science of heteroepitaxial growth.
References
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Journal ArticleDOI
Resonant tunneling in semiconductor double barriers
TL;DR: In this article, a double-barrier structure with a thin GaAs sandwiched between two GaAlas barriers has been shown to have resonance in the tunneling current at voltages near the quasistationary states of the potential well.
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Resonant tunneling through quantum wells at frequencies up to 2.5 THz
TL;DR: In this paper, a single quantum well of GaAs has been observed, and the current singularity and negative resistance region are dramatically improved over previous results, and detecting and mixing have been carried out at frequencies as high as 2.5 THz.
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High-frequency negative-resistance circuit principles for Esaki diode applications
TL;DR: In this paper, the conditions necessary for oscillation and amplification with a single negative-resistance diode, including stability criteria, gain and bandwidth, were discussed. But the conditions for one-port oscillator circuits and for traveling-wave amplifier circuits were not discussed.
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Demonstration of a new oscillator based on real‐space transfer in heterojunctions
TL;DR: In this paper, a real-space transfer oscillator was demonstrated in a layered GaAs/nAlGaAs heterojunction, where a dc bias field plus the ac oscillating field was applied parallel to the layer interfaces to modulate the electron transfer from the GaAs layers to the nAl-GaAs layers, resulting in the ac current being 180° out of phase with the ac voltage and power being generated.
Journal ArticleDOI
Millimeter-wave point-contact and junction diodes
TL;DR: In this article, the use of millimeter-wave point-contact diodes as detectors, amplifiers, oscillators, harmonic generators, and modulators is discussed, and the best reported performance characteristics in various millimeterwave applications are compared.