523 citations · 2.3k across the 46 of their papers we have counts for
29 papers · 1 filter
Inverse design of artificial two-level systems with Mössbauer nuclei in thin-film cavities
Oliver Diekmann, Dominik Lentrodt, Jörg Evers
Thin-film cavities containing layers of Mössbauer nuclei have been demonstrated to be a rich platform for x-ray quantum optics. At low excitation, these systems can be described by…
Spontaneous decay processes in a classical strong low-frequency laser field
M. Macovei, J. Evers, C. H. Keitel
The spontaneous emission of an excited two-level emitter driven by a strong classical coherent low-frequency electromagnetic field is investigated. We find that for relatively stro…
Phase-sensitive nuclear target spectroscopy (PHANTASY)
Benedikt Herkommer, Jörg Evers
Mössbauer nuclei feature exceptionally narrow resonances at hard x-ray energies, which render them ideal probes for structure and dynamics in condensed-matter systems, and a promis…
Coherent x-ray-optical control of nuclear excitons with zeptosecond phase-stability
K. P. Heeg, A. Kaldun, C. Strohm +11
Coherent control of quantum dynamics is key to a multitude of fundamental studies and applications alike. In the visible or longer-wavelength domains, near-resonant light fields ha…
Coherence and visibility in Fano interferometers
Fabian Lauble, Jörg Evers
Interferometry is an indispensable tool across all the natural sciences. Recently, a new type of interferometer based on phase-sensitive Fano resonances has been proposed and imple…
Probing Quantum Dynamical Couple Correlations with Time-Domain Interferometry
Salvatore Castrignano, Jörg Evers
Time domain interferometry is a promising method to characterizes spatial and temporal correlations at x-ray energies, via the so-called intermediate scattering function and the re…
Violating the no-signaling principle with classical inseparable beams in an optical parity-time symmetric system
Lida Zhang, Jörg Evers
We show that the no-signaling principle can be violated with classical inseparable beams in the presence of a parity-time (PT) symmetric subsystem. Thus, the problems associated to…
Collective dynamics in a laser-pumped mixture of two atomic ensembles
Luling Jin, Jörg Evers, Mihai Macovei
We investigate the quantum dynamics of an atomic mixture composed of two multi-atom ensembles. Each ensemble is driven separately by a coherent laser field, respectively, and dampe…
Pulse-splitting in light propagation through -type atomic media due to an interplay of Kerr-nonlinearity and group velocity dispersion
Rajitha K. V., Tarak N. Dey, Jörg Evers +1
We investigate the spatio-temporal evolution of a Gaussian probe pulse propagating through a four-level -type atomic medium. At two-photon resonance of probe-and control fields,…
Tailoring superradiance to design artificial quantum systems
Paolo Longo, Christoph H. Keitel, Jörg Evers
Cooperative phenomena arising due to the coupling of individual atoms via the radiation field are a cornerstone of modern quantum and optical physics. Recent experiments on x-ray q…
Tunable sub-luminal propagation of narrowband x-ray pulses
K. P. Heeg, J. Haber, D. Schumacher +9
Group velocity control is demonstrated for x-ray photons of 14.4 keV energy via a direct measurement of the temporal delay imposed on spectrally narrow x-ray pulses. Sub-luminal li…
Controllable linear -phase modulation in a thermal atom vapor without diffraction or absorption
Lida Zhang, Jörg Evers
A scheme is proposed to achieve substantial controllable phase modulation for a probe field propagating through a thermal atomic vapor in double- configuration. The phase modula…
Far-Field Signatures of a Two-Body Bound State in Collective Emission from Interacting Two-Level Atoms on a Lattice
Paolo Longo, Jörg Evers
The collective emission from a one-dimensional chain of interacting two-level atoms is investigated. We calculate the light scattered by dissipative few-excitation eigenstates in t…
Vacuum-assisted generation and control of atomic coherences at x-ray energies
Kilian P. Heeg, Hans-Christian Wille, Kai Schlage +9
The control of light-matter interaction at the quantum level usually requires coherent laser fields. But already an exchange of virtual photons with the electromagnetic vacuum fiel…
Direct detection of n-particle atomic correlations via light scattering
L. Jin, M. Macovei, J. Evers
The creation and direct detection of n-particle atomic correlations in ensembles of atoms is investigated. For this, we study an ensemble of laser-driven atoms in which either a di…
Pathway interference in a loop array of three coupled microresonators
Sandra Isabelle Schmid, Keyu Xia, Jörg Evers
A system of three coupled toroidal microresonators arranged in a loop configuration is studied. This setup allows light entering the resonator setup from a tapered fiber to evolve…
Dressed-atom multiphoton analysis of anomalous electromagnetically induced absorption
H. -S. Chou, J. Evers
A method to interpret probe spectra of driven degenerate atomic systems is discussed. The dressed-atom multiphoton spectroscopy (DAMS) is based on a dressing of the atomic system w…
Coherent control of nuclear forward scattering
Adriana Pálffy, Jörg Evers
The possibility to control the coherent decay of resonant excitations in nuclear forward scattering is investigated. By changing abruptly the direction of the nuclear hyperfine mag…
Quantum entanglement in dense multiqubit systems
M. Macovei, J. Evers, C. H. Keitel
The pairwise entanglement of an arbitrary atomic pair randomly extracted from a laser-driven dense multiqubit sample in the presence of quantum dissipation due to spontaneous emiss…
Light propagation in chiral media
R. Fleischhaker, J. Evers
Light propagation in chiral media is discussed. We derive the wave equations for a probe pulse propagating through a chiral medium, and solve them analytically in Fourier space usi…
Ground state cooling of a nanomechanical resonator in the weak-confinement regime via quantum interference
K. Xia, J. Evers
Ground state cooling of a nanomechanical resonator coupled to a superconducting flux qubit is discussed. We show that by inducing quantum interference to cancel detrimental carrier…
Four-wave mixing enhanced white-light cavity
R. Fleischhaker, J. Evers
We discuss in-medium propagation dynamics in a white light cavity that leads to an enhancement of the cavity's bandwidth without reducing its maximum intensity buildup. We analyze…
Nonlinear Effects in Pulse Propagation through Doppler-Broadened Closed-Loop Atomic Media
Robert Fleischhaker, Jörg Evers
Nonlinear effects in pulse propagation through a medium consisting of four-level double--type systems are studied theoretically. We apply three continous-wave driving fields and…
Negative refraction with tunable absorption in an active dense gas of atoms
P. P. Orth, R. Hennig, C. H. Keitel +1
Applications of negative index materials (NIM) presently are severely limited by absorption. Next to improvements of metamaterial designs, it has been suggested that dense gases of…