Results 231 to 240 of about 1,396,787 (284)
Some of the next articles are maybe not open access.
Terahertz Quantum Cascade Lasers
SPIE Proceedings, 2003Unipolar semiconductor injection lasers emitting at THz frequencies (from 4.3 THz down to 2.8 THz) are discussed. The devices are based on interminiband transitions in chirped GaAs/AlGaAs superlattices that are arranged in a quantum-cascade scheme. The core, featuring about 100 repetitions of this type of superlattice, is embedded into a novel kind of ...
R. Köhler +6 more
+10 more sources
Science, 1994
A semiconductor injection laser that differs in a fundamental way from diode lasers has been demonstrated. It is built out of quantum semiconductor structures that were grown by molecular beam epitaxy and designed by band structure engineering. Electrons streaming down a potential staircase sequentially emit photons at the steps.
J, Faist +5 more
openaire +2 more sources
A semiconductor injection laser that differs in a fundamental way from diode lasers has been demonstrated. It is built out of quantum semiconductor structures that were grown by molecular beam epitaxy and designed by band structure engineering. Electrons streaming down a potential staircase sequentially emit photons at the steps.
J, Faist +5 more
openaire +2 more sources
Mid-infrared quantum cascade lasers [PDF]
Nature Photonics, 2012 Quantum cascade lasers (QCL) based on intersubband transitions operating at room temperature in the mid-infrared or `molecular ngerprint' spectral region (3.4{17 m) have been found useful for several applications including environmental sensing ...
Anthony Hoffman +2 more
exaly +2 more sources
Quantum Optoelectronics, 1995
The recently demonstrated quantum cascade laser is a fundamentally new semiconductor laser.1-3 It relies on only one type of carrier (unipolar laser) and on quantum jumps of electrons between discrete conduction band energy levels of quantum wells. As such the wavelength can be tailored over a very wide range from the mid-ir (a few microns) to the far ...
F. Capasso, J. Faist
openaire +1 more source
The recently demonstrated quantum cascade laser is a fundamentally new semiconductor laser.1-3 It relies on only one type of carrier (unipolar laser) and on quantum jumps of electrons between discrete conduction band energy levels of quantum wells. As such the wavelength can be tailored over a very wide range from the mid-ir (a few microns) to the far ...
F. Capasso, J. Faist
openaire +1 more source
Physics Today, 1999
Band-structure engineering has led to a fundamentally new laser with applications ranging from highly sensitive trace-gas analysis to communications.
Federico Capasso +3 more
openaire +2 more sources
Band-structure engineering has led to a fundamentally new laser with applications ranging from highly sensitive trace-gas analysis to communications.
Federico Capasso +3 more
openaire +2 more sources
2009
As a result of mass production, millions of semiconductor diode lasers are manufactured each month and appear in products ranging from telecommunications transmitters to DVD players and laser pointers. For traditional laser diodes, the applications are often dictated by what part of the electromagnetic spectrum is accessible.
openaire +2 more sources
As a result of mass production, millions of semiconductor diode lasers are manufactured each month and appear in products ranging from telecommunications transmitters to DVD players and laser pointers. For traditional laser diodes, the applications are often dictated by what part of the electromagnetic spectrum is accessible.
openaire +2 more sources
Terahertz Quantum Cascade Lasers
Asia Optical Fiber Communication and Optoelectronic Exposition and Conference, 2007Six years after their birth, terahertz quantum-cascade lasers can now deliver milliwatts or more of continuous-wave coherent radiation throughout the terahertz range — the spectral regime between millimetre and infrared wavelengths, which has long resisted development.
openaire +1 more source
Conference on Lasers and Electro-Optics-Europe, 1998
By controlling the quantum well widths and the tunnelling barrier thickness of heterostructures it is possible to create artificial potentials where level separations, dipole matrix elements, lifetimes and scattering times are dependent on the potential design.
C. Sirtori +4 more
openaire +1 more source
By controlling the quantum well widths and the tunnelling barrier thickness of heterostructures it is possible to create artificial potentials where level separations, dipole matrix elements, lifetimes and scattering times are dependent on the potential design.
C. Sirtori +4 more
openaire +1 more source
2013
THz sources are the fundamental requirement for THz technology even for passive detection systems where sources are required for heterodyne detection to improve detectivity. A review is given for one such THz source, the quantum cascade laser. Quantum cascade lasers are unipolar, intersubband photon emitters that can be tuned through the width of ...
openaire +2 more sources
THz sources are the fundamental requirement for THz technology even for passive detection systems where sources are required for heterodyne detection to improve detectivity. A review is given for one such THz source, the quantum cascade laser. Quantum cascade lasers are unipolar, intersubband photon emitters that can be tuned through the width of ...
openaire +2 more sources
2017
The quantum cascade laser represents an important accomplishment in quantum photonics, combining quantum excitation of the electromagnetic field, electron transport and controllable quantum mechanical tunneling all working cooperatively in a single device. In cascade lasers, the carriers are “recycled” from one stage to the next, so that the evacuation
openaire +1 more source
The quantum cascade laser represents an important accomplishment in quantum photonics, combining quantum excitation of the electromagnetic field, electron transport and controllable quantum mechanical tunneling all working cooperatively in a single device. In cascade lasers, the carriers are “recycled” from one stage to the next, so that the evacuation
openaire +1 more source