Full-time nonexponential decay in double-barrier quantum structures

Quantum noise in ac-driven resonant-tunneling double-barrier structures: Photon-assisted tunneling versus electron antibunching

We study the quantum noise of the electronic current in a double-barrier system with a single resonant level. In the framework of the Landauer formalism, we treat the double barrier as a quantum coherent scattering region that can exchange photons with a coupled electric field, e.g., a laser beam or a periodic ac bias voltage. As a consequence of the manifold parameters that are involved in thi...

Controversy about Quantum Time Decay

Nonexponential Fluorescence Decay of Tryptophan, Tryptophylglycine, and Glycyltryptophan

The photophysics and spectroscopy of tryptophylglycine, tryptophylalanine, glycyltryptophan, alanyltryptophan, glycyltryptophylglycine, and tryptophan itself have been investigated by using steady-state and subnanosecond spectroscopy. For tryptophan and the peptides where the tryptophyl residue is N-terminal we demonstrate the involvement of the state of protonation on both the excited-state dy...

Analytical Expression for the Tunneling Time in Symmetrical Rectangular Double-Barrier Structures

An analytical expression for the electron tunneling time has been derived for symmetrical rectangular double-barrier structures. It gives values of the tunneling time equal to those calculated by the dwell time method for the resonant tunneling state. The obtained tunneling time is given by the sum of the time connected with the barrier layer width and the time connected with the well layer wid...

Nonparabolicity effects and the spin-split electron dwell time in symmetric III-V double-barrier structures

We start from the fourth-order nonparabolic and anisotropic conduction band bulk dispersion relation to obtain a one-band effective Hamiltonian, which we apply to an AlGaSb symmetric double-barrier structure with resonant energies significantly (more than 200 meV) above the well bottom. The spin-splitting is described by the k(3) Dresselhaus spin-orbit coupling term modifying only the effective...