Search results for "Stimulated Raman adiabatic passage"
showing 10 items of 23 documents
Stimulated Raman adiabatic passage in a $\Lambda$-system in the presence of quantum noise
2011
We exploit a microscopically derived master equation for the study of STIRAP in the presence of decay from the auxiliary level toward the initial and final state, and compare our results with the predictions obtained from a phenomenological model previously used [P. A. Ivanov, N. V. Vitanov, and K. Bergmann, Phys. Rev. A 72, 053412 (2005)]. It is shown that our approach predicts a much higher efficiency. The effects of temperature are also taken into account, proving that in b-STIRAP thermal pumping can increase the efficiency of the population transfer.
Stimulated Raman adiabatic passage in an open quantum system: Master equation approach
2010
A master equation approach to the study of environmental effects in the adiabatic population transfer in three-state systems is presented. A systematic comparison with the non-Hermitian Hamiltonian approach [N. V. Vitanov and S. Stenholm, Phys. Rev. A {\bf 56}, 1463 (1997)] shows that in the weak coupling limit the two treatments lead to essentially the same results. Instead, in the strong damping limit the predictions are quite different: in particular the counterintuitive sequences in the STIRAP scheme turn out to be much more efficient than expected before. This point is explained in terms of quantum Zeno dynamics.
Theory of the bright-state stimulated Raman adiabatic passage
2009
We describe analytically and numerically the process of population transfer by stimulated Raman adiabatic passage through a bright state when the pulses propagate in a medium. Limitations of the adiabaticity are analyzed and interpreted in terms of reshaping of the pulses. We find parameters for the pulses for which the population transfer is nearly complete over long distances.
The branching ratio of intercombination A1Σ+∼b3Π→a3Σ+/X1Σ+transitions in the RbCs molecule: Measurements and calculations
2020
Abstract We observed the A 1 Σ + ∼ b 3 Π → a 3 Σ + / X 1 Σ + laser-induced fluorescence (LIF) of the RbCs molecule excited from the ground X 1 Σ + state by the Ti:Sapphire laser. The LIF spectra from the common perturbed levels of the singlet-triplet A ∼ b complex was recorded by the Fourier-transform (FT) spectrometer with the instrumental resolution of 0.03 cm − 1 . The relative intensity distribution in the rotationally resolved A ∼ b → a 3 Σ + ( v a ) / X 1 Σ + ( v X ) progressions was measured, and their branching ratio was found to be about of 1 ÷ 5 × 10 − 4 in the bound region of the a 3 Σ + and X 1 Σ + states. The experiment was complemented with the scalar- and full-relativistic ca…
Topology of adiabatic passage
2002
We examine the topology of eigenenergy surfaces characterizing the population transfer processes based on adiabatic passage. We show that this topology is the essential feature for the analysis of the population transfers and the prediction of its final result. We reinterpret diverse known processes, such as stimulated Raman adiabatic passage (STIRAP), frequency-chirped adiabatic passage and Stark-chirped rapid adiabatic passage. Moreover, using this picture, we display new related possibilities of transfer. In particular, we show that we can selectively control the level that will be populated in STIRAP process in $\ensuremath{\Lambda}$ or V systems by the choice of the peak amplitudes or …
Design of a Lambda system for population transfer in superconducting nanocircuits
2013
The implementation of a Lambda scheme in superconducting artificial atoms could allow detec- tion of stimulated Raman adiabatic passage (STIRAP) and other quantum manipulations in the microwave regime. However symmetries which on one hand protect the system against decoherence, yield selection rules which may cancel coupling to the pump external drive. The tradeoff between efficient coupling and decoherence due to broad-band colored Noise (BBCN), which is often the main source of decoherence is addressed, in the class of nanodevices based on the Cooper pair box (CPB) design. We study transfer efficiency by STIRAP, showing that substantial efficiency is achieved for off-symmetric bias only i…
Quantum plasmonics with multi-emitters: application to stimulated Raman adiabatic passage
2018
We construct a mode-selective effective model describing the interaction of the localised surface plasmon polaritons (LSPs) supported by a spherical metal nanoparticle (MNP) with N quantum emitters (QEs) in an arbitrary geometric arrangement. Simplifying previously presented procedures, we develop a formulation in which the field response in the presence of the MNP can be decomposed into orthogonal modes, expanding the Green tensor of the system in the spherical vector harmonics basis and using the generalized global Löwdin orthogonalization algorithm. We investigate the possibility of using the LSPs as mediators of an efficient control of population transfer between two QEs. We show that a…
EFFECT OF LOW-FREQUENCY NOISE ON ADIABATIC PASSAGE IN A SUPERCONDUCTING NANOCIRCUIT
2011
Recent experiments have demonstrated coherent phenomena in three-level systems based on superconducting nanocircuits. This opens the possibility to detect Stimulated Raman Adiabatic Passage (STIRAP) in artificial atoms. Low-fequency noise (often 1/f) is one of the main sources of decoherence in these systems, and we study its effect on the transfer efficiency. We propose a way to analyze low frequency fluctuations in terms of fictitious correlated fluctuations of external parameters. We discuss a specific implementation, namely the Quantronium setup of a Cooper-pair box, showing that optimizing the trade-off between efficient coupling and protection against noise may allow us to observe co…
Detuning effects in STIRAP processes in the presence of quantum noise
2011
The Stimulated Raman adiabatic passage (STIRAP) in three-state systems in the presence of quantum noise is considered. A comparison is made between different models, one based on a phenomenological introduction of decays, one traceable back to a microscopic description of the system-environment interaction. Effects related, to off-resonance in the coupling between the involved states are considered.
INFLUENCE OF UNEQUAL OSCILLATOR STRENGTHS ON STIMULATED RAMAN ADIABATIC PASSAGE THROUGH BRIGHT STATE
2012
In the present work an analytical and numerical analysis of the b -STIRAP process in a medium with unequal oscillator strengths is performed. It is shown that the length of population transfer can be considerably increased by an appropriate choice of the dipole transitions.