Coherent population transfer in molecules coupled with a dissipative environment by an intense ultrashort chirped pulse

Abstract

Population transfer to excited vibrational levels of H 2 molecule by stimulated hyper-Raman passage with chirped laser pulses Erratum: "Coherent population transfer in molecules coupled with a dissipative environment by intense ultrashort chirped pulse" [J.We have studied the intense chirped pulse excitation of a molecule coupled with a dissipative environment taking into account electronic coherence effects. We considered a two-state electronic system with relaxation treated as a diffusion on electronic potential energy surfaces. This relaxation model enables us to trace continuously the transition from a coherent population transfer to incoherent one. An inhomogeneously broadened system with frozen nuclear motion is invoked to model a purely coherent transfer. We show that the type of population transfer ͑coherent or incoherent͒ strongly depends on the pulse chirp, its sign, and the detunings of the exciting pulse carrier frequency with respect to the frequency of the Franck-Condon transition. For positive chirped pulses and moderate detunings, relaxation does not hinder a coherent population transfer. Moreover, under these conditions the relaxation favors more efficient population transfer with respect to the ''coherent'' system with frozen nuclear motion.

Adiabatic Passage in a Three-State System with Non-Markovian Relaxation: The Role of Excited-State Absorption and Two-Exciton Processes

“…Going to a dimensionless generalized coordinate x = qω √ β, one can obtain the equations for the elements of the density matrix ρ ij (x, t) by the generalization of the equations of Ref. [26]. Switching to the system that rotates with instantaneous frequency…”

“…on the right-hand side of the corresponding equation for the nondiagonal element of the density matrix [26,40,12,41] that describes relaxation (diffusion) ofρ ij (x, t) (Eqs. (6) and (8)).…”

“…(5)- (8), using a basis set expansion with eigenfunctions of diffusion operator L 13 , similar to Ref. [26].…”

“…It has been shown in Ref. [26] that relaxation does not hinder a coherent population transfer for positive chirped pulses and moderate detuning of the central pulse frequency with respect to the frequency of Franck-Condon transition.…”

Simultaneous control of optical dipole force and coherence creation by super-Gaussian femtosecond pulses inΛ-like atomic systems

“…Today, coherent control techniques are widely used in the fields of robust quantum dot excitation generation [18], controllable coherent population transfer in superconducting qubits [19], atomic interferometry [20,21], high precession spectroscopy [22,23], quantum computing [24,25], quantum information processing [26,27], ultrafast optical switching [28][29][30] and population transfer in four level atoms [31]. In the last two or three decades or so, many efficient schemes such as stimulated Raman adiabatic passage (STIRAP), Raman chirped adiabatic passage (RCAP) and adiabatic rapid passage (ARP) for controlling the population transfer between the quantum states of atoms and molecules has opened new routes for controlling the various atomic and molecular processes [1,2,[32][33][34]. In this context, another extremely important and relevant topic of interest is the creation of coherent superposition of atomic or molecular quantum states or coherence.…”