Related papers: Free carrier absorption in quantum cascade structu…
We present a viewpoint of the transport process in quantum cascade laser structures in which spatial transport of charge through the structure is a property of coherent quantum-mechanical wavefunctions. In contrast, scattering processes…
General expressions are obtained for the coefficient of light absorption by free carriers as well as the intensity of the spontaneous light emission by hot electrons in multivalley semiconductors. These expressions depend on the electron…
Quantum acoustics -- a recently developed framework parallel to quantum optics -- establishesa nonperturbative and coherent treatment of the electron-phonon interaction in real space. The quantum-acoustical representation reveals a…
We present a theory for the intersubband absorption including electronic ground state correlations in a doped GaAs/Al_{35}Ga_{65}As quantum well system. Focusing on the influence of the Coulomb interaction among the carriers at low…
The transport in complex multiple quantum well heterostructures is theoretically described. The model is focused on quantum cascade detectors, which represent an exciting challenge due to the complexity of the structure containing 7 or 8…
We obtain the conductance of a system of electrons connected to leads, within time-dependent density-functional theory, using a direct relation between the conductance and the density response function. Corrections to the non-interacting…
A quantum cascade laser where the quantum wells in the active regions are replaced by quantum dots with their atom-like discrete energy levels is an interesting system to study novel features in optical spectroscopy. We study structures…
In this paper, we analyse the optical absorption in porous silicon . This is the first attempt to explicitly demonstrate that it is not possible to extract the band gap of such low dimensional nanostructures like porous silicon from a Tauc…
In the lectures we will be concerned with some aspects of physical implementations of quantum gate operations which are necessary for quantum information processing. We will discuss two possible realizations. One of them is based on qubits…
Among the various attempts to understand collisionless absorption of intense ultrashort laser pulses a variety of models has been invented to describe the laser beam target interaction. In terms of basic physics collisionless absorption is…
An optical transmitter that uses entangled light generated by spontaneous parametric downconversion (SPDC), in conjunction with an optimal quantum-optical receiver (whose implementation is not yet known) is in principle capable of obtaining…
We develop a free-carrier theory of the optical absorption of light carrying orbital angular momentum (twisted light) by bulk semiconductors. We obtain the optical transition matrix elements for Bessel-mode twisted light and use them to…
The unusual properties of two-dimensional electron systems that give rise to the quantum Hall effect have prompted the development of new microscopic models for electrical conduction. The bulk properties of the quantum Hall effect have also…
Interpretation of experiments on quantum dot (QD) lasers presents a challenge: the phonon bottleneck, which should strongly suppress relaxation and dephasing of the discrete energy states, often seems to be inoperative. We suggest and…
A theoretical study on low-threshold multimode instabilities in quantum cascade lasers (QCLs) and laser diodes (LDs) is presented. Previously, low threshold Risken-Nummedal-Graham-Haken (RNGH) instabilities were reported in several…
We report the coherent phase-locking of a quantum cascade laser (QCL) at 10-$\mu$m to the secondary frequency standard of this spectral region, a CO2 laser stabilized on a saturated absorption line of OsO4. The stability and accuracy of the…
In a previous Letter [Phys. Rev. Lett. 96, 123401 (2006)] we have shown by means of three-dimensional particle-in-cell simulations and a simple rigid-sphere model that nonlinear resonance absorption is the dominant collisionless absorption…
We have performed detailed photoluminescence (PL) and absorption spectroscopy on the same single self-assembled quantum dot in a charge-tunable device. The transition from neutral to charged exciton in the PL occurs at a more negative…
Light absorption at the boundary of indirect-band-gap and direct-forbidden gap semiconductors is analyzed. It is found that the possibility of the electron momentum nonconservation at the interface leads to essential enhancement of…
In this work we consider a current carrying two level quantum dot(QD) that is coupled to a single mode phonon bath. Using self-consistent Hartree-Fock approximation, we obtain the I-V curve of QD. By considering the linear response of our…