Now showing items 1-10 of 1299
Enhancement of quantum speed limit time due to cooperative effects in multilevel systems
(IOP Publishing, 2015-08)
Deriving minimum evolution times is of paramount importance in quantum mechanics. Bounds on the speed of evolution are given by the so called quantum speed limit (QSL). In this work we use quantum optimal control methods ...
Selective and efficient quantum state tomography and its application to quantum process tomography
(American Physical Society, 2013-01-18)
We present a method for quantum state tomography that enables the efficient estimation, with fixed precision, of any of the matrix elements of the density matrix of a state, provided that the states from the basis in which ...
Spontaneous spin polatization in doped semiconductor quantum wells
We calculate the critical density of the zero-temperature, first-order ferromagnetic phase transition in n-doped GaAs/AlGaAs quantum wells. We predict that this transition could be observed in narrow quantum wells at ...
Effect of the Rashba and Dresselhaus spin-splitting terms on the electron g factor in semiconductor quantum wells under applied magnetic fields
We use the Ogg-McCombe Hamiltonian together with the Dresselhaus and Rashba spin-splitting terms to find the g factor of conduction electrons in GaAs-(Ga,Al)As semiconductor quantum wells (QWS) (either symmetric or asymmetric) ...
QUANTUM HALL FERROMAGNET IN A DOUBLE WELL WITH VANISHING g-FACTOR.
(WORLD SCIENTIFIC PUBL CO PTE LTD, 2009)
We have studied the quantum Hall effect in Al(x)Ga(1-x)As-double well structure with vanishing g-factor. We determined the density-magnetic field n(s) - B diagrams for the longitudinal resistance R(xx). In spite of the ...
Electronic structure of holes in modulation doped p-Si1-xGex/Si strained quantum wells in a magnetic field
(Pergamon-elsevier Science LtdOxfordInglaterra, 1998)
A discussion on particle number and quantum indistinguishability
The concept of individuality in quantum mechanics shows radical differences from the concept of individuality in classical physics, as E. Schrödinger pointed out in the early steps of the theory. Regarding this fact, some ...
Optical properties of remotely doped parabolic quantum wells
(Elsevier B.V., 2003-04-01)
This work is intended to report on optical measurements in a parabolic quantum well with a two dimensional-three dimensional electron gas. Photoluminescence results show broad spectra which are related to emission involving ...
Local approximation to the critical parameters of quantum wells
We calculate the critical parameters for some simple quantum wells by means of the Riccati–Padé method. The original approach converges reasonably well for nonzero angular-momentum quantum number l but rather too slowly ...
Effect of resonant tunneling on exciton dynamics in coupled dot-well nanostructures
(American Institute of Physics - AIPCollege Park, 2013-04)
Excitonic dynamics in a hybrid dot-well system composed of InAs quantum dots (QDs) and an InGaAs quantum well (QW) is studied by means of femtosecond pump-probe reflection and continuous wave (cw) photoluminescence (PL) ...