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We propose a modified Stark-chirped rapid adiabatic passage technique for a robust rovibrational population transfer in the gas phase molecules in the presence of certain inhomogeneous electric fields. As an example application, the new…

Atomic Physics · Physics 2025-06-06 Emil Zak , Jochen Küpper , Andrey Yachmenev

We investigate the depletion of single-electron states in small molecules under the influence of very short XUV pulses. In N$_2$, for a certain window of XUV energies around 50 eV, we observe a marked occupation inversion, i.e. a situation…

Atomic and Molecular Clusters · Physics 2023-03-01 Paul-Gerhard Reinhard , Daniel Dundas , Phuong Mai Dinh , Marc Vincendon , Eric Suraud

By periodical two-step modulation, we demonstrate that the dynamics of multilevel system can still evolve even in multiple large detunings regime, and provide the effective Hamiltonian (of interest) for this system. We then illustrate this…

Quantum Physics · Physics 2018-12-27 Zhi-Cheng Shi , Du Ran , Li-Tuo Shen , Yan Xia , X. X. Yi

We study the nonlinear and resonant process of two-photon ionization of atoms (He and H) in a pump-probe scheme. The pump pulse prepares the quantum system in a superposition of the ground state and an excited bound state. By varying the…

The density matrix of a two-level system (spin, atom) is usually determined by measuring the three non-commuting components of the Pauli vector. This density matrix can also be obtained via the measurement data of two commuting variables,…

Quantum Physics · Physics 2012-05-25 B. Mehmani , A. E. Allahverdyan , Th. M. Nieuwenhuizen

We create a dark optical lattice structure using a blue detuned laser field coupling an atomic ground state of total angular momentum F simultaneously to two excited states with angular momenta F and F-1, or F and F+1. The atoms are trapped…

Atomic Physics · Physics 2008-02-03 Frank Sander , Tilman Esslinger , Theodor W. Hansch , Herwig Stecher , Helmut Ritsch

We have observed spontaneous symmetry breaking of atomic populations in the dynamic phase-space double-potential system, which is produced in the parametrically driven magneto-optical trap of atoms. We find that the system exhibits similar…

Atomic Physics · Physics 2009-11-11 Kihwan Kim , Myoung-Sun Heo , Ki-Hwan Lee , Kiyoub Jang , Heung-Ryoul Noh , Doochul Kim , Wonho Jhe

The time evolution of driven two-level systems in the far off-resonance regime is studied analytically. We obtain a general first-order perturbative expression for the time-dependent density operator which is applicable regardless of the…

Quantum Physics · Physics 2010-07-01 V. Delgado , J. M. Gomez Llorente

The steady state in three-level lambda and ladder systems is studied. It is well-known that in a lambda system this steady state is the coherent population trapping state, independent of the presence of spontaneous emission. In contrast,…

Atomic Physics · Physics 2009-10-30 M. Blaauboer

A 2-level atom with degenerate ground state interacting with a quantum field is investigated. We show, that the field drives the state of the atom to a stationary state, which is non-unique, but depends on the initial state of the system…

Quantum Physics · Physics 2015-06-26 L. Accardi , S. V. Kozyrev

We propose a multilevel scheme to coherently transfer the population of a diatomic molecule from a rovibrational level to a target rovibrational level of the same electronic state or another. It involves a linear chain of N rovibrational…

Quantum Physics · Physics 2024-12-11 Diego F. Uribe , Mateo Londoño , Julio C. Arce

We show that radiative coupling between two multilevel atoms having near-degenerate states can produce new interference effects in spontaneous emission. We explicitly demonstrate this possibility by considering two identical V systems each…

Quantum Physics · Physics 2009-11-06 G. S. Agarwal , Anil K. Patnaik

We report studies of state-to-state vibrational energy transfer in an isolated polyatomic molecule driven by combined stimulated Raman adiabatic passage (STIRAP) and counter-diabatic fields (CDF), using as vehicles selective population of…

Quantum Physics · Physics 2014-09-03 Shumpei Masuda , Stuart A. Rice

Up to now, experiments involving M\"ossbauer nuclei driven by x-rays have been restricted to the low-excitation regime. Here, a setup is proposed which promises significant excitation, ideally exceeding full inversion of the nuclear…

Quantum Physics · Physics 2016-07-15 K. P. Heeg , C. H. Keitel , J. Evers

A robust system for use of Quantum Computation using neutral atoms is presented in this communication. This scheme exploits a multilevel atomic system interacting with two lasers in such a way that it leads to formation of two Coherent…

Quantum Physics · Physics 2012-09-03 Ashok Vudayagiri

An observer-based Hamiltonian identification algorithm for quantum systems has been proposed recently by Bonnabel et al. The later paper provided a method to estimate the dipole moment matrix of a quantum system requiring the measurement of…

Quantum Physics · Physics 2012-02-27 Zaki Leghtas , Mazyar Mirrahimi , Pierre Rouchon

We study theoretically the quantum dynamics of two interacting electrons in the symmetric double-dot structure under the influence of the bichromatic resonant pulse. The state vector evolution is studied for two different pulse designs. It…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Alexander V. Tsukanov

We analyze the stability of super- and subradiant states in a system of identical two-level atoms in the near-Dicke limit, i.e., when the atoms are very close to each other compared to the wavelength of resonant light. The dynamics of the…

Quantum Physics · Physics 2008-11-20 Peter G. Brooke , Karl-Peter Marzlin , James D. Cresser , Barry C. Sanders

We investigate the rovibrational population redistribution of polar molecules in the electronic ground state induced by spontaneous emission and blackbody radiation. As a model system we use optically trapped LiCs molecules formed by…

Atomic Physics · Physics 2015-05-28 J. Deiglmayr , M. Repp , O. Dulieu , R. Wester , M. Weidemüller

Switching anisotropic molecules from strongly-absorbing to strongly-amplifying through a transparent state is shown to be possible by application of dc or ac control electric fields without the requirement of the population inversion. It is…

Quantum Physics · Physics 2015-06-26 A. K. Popov , V. V. Slabko
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