Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review Research

Probing the dissipation process via a Fano resonance and collective effects in an x-ray cavity

Tian-Jun Li, Xin‐Chao Huang, Zi-Ru Ma, Bo Li, Lin‐Fan Zhu

Published Apr 28, 2022• 6 citations
Publisher

Abstract

In the absence of time-reversal symmetry, the asymmetric parameter $q$ of the Fano resonance is extended into the complex space, where its trajectory can be utilized to investigate the decoherence process. By embedding the ensemble of M$\stackrel{\ifmmode \ddot{}\else \"{}\fi{}}{\mathrm{o}}$ssbauer nuclei in the thin-film planar cavity in this work, the trajectories of asymmetric parameter $q$ are studied via the collective effect of the nuclear ensemble, which is regulated by the nuclear abundance and angle offset. Due to the diverse controllable methods of the collective resonant strength, there are different straight lines and arc-shaped trajectories in the complex plane, in which the slopes and the radius can be adjusted by the angle offset and nuclear abundance, respectively. It is demonstrated that the dissipation process can be ``suppressed'' equivalently by the strong energy exchange between the cavity and the nuclear ensemble. The present results could enrich the behaviors of the asymmetric parameter $q$ in the complex plane and would provide a new opportunity for decoherence research through the thin-film planar cavity.

DOI
10.1103/physrevresearch.4.023081

Related papers

Probing dissipation process via Fano resonance and collective effect in the X-ray cavity

Li, Tian-Jun, Xin‐Chao Huang, Zi-Ru Ma +2 more

In the absence of time-reversal symmetry, the asymmetric parameter q of the Fano resonance is extended into the complex space, where its trajectory can be utilized to investigate the decoherence process. By embedding the ensemble of M$\ddot{\rm{o}}$ssbauer nuclei in the thin-film planar cavity in this work, the trajectories of asymmetric parameter q are studied via the collective effect of the nuclear ensemble, which is regulated by the nuclear abundance and angle offset. Due to the diverse controllable methods of the collective resonant strength, there are different straight lines and arc-shape trajectories in the complex plane, in which the slopes and the radius can be respectively adjusted by the angle offset and nuclear abundance. It is demonstrated that the dissipation process can be suppressed equivalently by the strong energy exchange between the cavity and nuclear ensemble. The present results could enrich the behaviors of the asymmetric parameter q in the complex plane and would provide new possibility for the decoherence research through the thin-film planar cavity.

arXiv:2201.01098•Jan 4, 2022•0 citations

Fano-Lorentz shape controlled by the collective effect of the nuclear ensemble

Tian-Jun Li, Xin‐Chao Huang, Zi-Ru Ma +3 more

The thin-film planar cavity implanted in the $\mathrm{M}\stackrel{\ifmmode \ddot{}\else \"{}\fi{}}{\mathrm{o}}\mathrm{ssbauer}$ nuclei has been developed as a powerful platform to study the light-matter interaction in the x-ray band. Herein the asymmetric and symmetric profiles of Fano interference are studied by controlling the collective effect and modifying the cavity structure. It is found that the asymmetric profiles in the overcritical and undercritical regimes are the Fano-Lorentz shape, and the asymmetry of the profile is determined by $\mathrm{cos}\ensuremath{\varphi}$ rather than $\mathrm{cot}\ensuremath{\varphi}$ in the framework of the initial Fano theory with $\ensuremath{\varphi}$ being the phase shift of the continuum. In addition, the Fano-Lorentz profile not only can be controlled by the phase difference of the two pathways, but also can be adjusted by the weight of the normal Fano resonance in the Fano-Lorentz profile through regulating the collective effect of the nuclear ensemble. By varying the nuclear abundance at the cavity mode angle, the transformation between the symmetric peak and valley is observed in the overcritical regime, whereas the symmetric peaks are always presented in the undercritical regime. Furthermore, a particularly interesting phenomenon of a flat reflectivity, as if the resonant nuclear ensemble is not excited, is predicted in the nuclear ensemble at a critical nuclear abundance in the overcritical regime. The present results will not only confirm the presence of the complex $q$, but also open up an avenue to study the decoherence processes via the Fano-Lorentz shape in the thin-film planar cavity.

Physical Review A•Sep 26, 2023•4 citations

Probing Decoherence through Fano Resonances

Andreas Bärnthaler, Stefan Rotter, Florian Libisch +4 more

We investigate the effect of decoherence on Fano resonances in wave transmission through resonant scattering structures. We show that the Fano asymmetry parameter q follows, as a function of the strength of decoherence, trajectories in the complex plane that reveal detailed information on the underlying decoherence process. Dissipation and unitary dephasing give rise to manifestly different trajectories. Our predictions are successfully tested against microwave experiments using metal cavities with different absorption coefficients and against previously published data on transport through quantum dots. These results open up new possibilities for studying the effect of decoherence in a wide array of physical systems where Fano resonances are present.

arXiv:1003.5381•Physical Review Letters•Jul 26, 2010•80 citations

Collective effects between multiple nuclear ensembles in an x-ray cavity-QED setup

Kilian P. Heeg, Jörg Evers

The setting of M\"ossbauer nuclei embedded in thin-film cavities has facilitated an aspiring platform for x-ray quantum optics as shown in several recent experiments. Here, we generalize the theoretical model of this platform that we developed earlier [Phys. Rev. A 88, 043828 (2013)]. The theory description is extended to cover multiple nuclear ensembles and multiple modes in the cavity. While the extensions separately do not lead to qualitatively new features, their combination gives rise to cooperative effects between the different nuclear ensembles and distinct spectral signatures in the observables. A related experiment by R\"ohlsberger et al. [Nature (London) 482, 199 (2012)] is successfully modeled, the scalings derived with semiclassical methods are reproduced, and a microscopic understanding of the setting is obtained with our quantum mechanical description.

arXiv:1504.02709•Physical Review A•Jun 3, 2015•29 citations

X-Ray Quantum Optics With Mössbauer Nuclei In Thin-Film Cavities

Kilian P. Heeg

In this thesis thin-film cavities with embedded Mössbauer nuclei probed by near-resonant x-ray light are studied from a quantum optical perspective. A theoretical framework is developed and compact expressions for the observables are derived for the linear excitation regime, which is encountered in current experiments. Even advanced cavity layouts can be modeled in excellent agreement with the results of previous experiments and semi-classical approaches. In the absence of magnetic hyperfine splitting, the spectral response of the system is found to be formed by tunable Fano profiles. An experimental implementation of this line shape control allows to extract spectroscopic signatures with high precision and to reconstruct the phase of the nuclear transition in good agreement with the theoretical predictions. The alignment of medium magnetization and polarization control of the x-rays enable to engineer advanced quantum optical level schemes, in which vacuum induced coherence effects are predicted and successfully demonstrated in an experiment. Furthermore, it is shown that group velocity control for x-ray pulses can be achieved in the cavity. A scheme for its observation is proposed and then employed to experimentally confirm sub-luminal x-ray propagation. Finally, non-linear effects, which could become accessible with future light sources, are explored and a non-linear line shape control mechanism is discussed.

•Jan 1, 2014•0 citations

Collective Dynamics of Nuclei from Quadrupole Splitting in an X-ray Cavity

xubo liao, Yue Wang, Kangjun Xia +3 more

Abstract Mössbauer nuclei with quadrupole-split levels provide a versatile platform for exploring coherent x-ray light-matter interactions. We theoretically study ensembles of 57 Fe nuclei embedded in thin-film x-ray cavities, explicitly accounting for different orientations of the electric field gradient. By mapping isotropic electric field gradient distributions to an effective equal-weight two-transition model, we derive analytical expressions for the time-dependent reflectivity and reveal the emergence of cavity-mediated quantum beats. The oscillation frequency and temporal profile of these beats can be tuned via the cavity-induced coherent coupling, offering a flexible approach to control collective nuclear dynamics and manipulate nuclear coherence in the x-ray regime.

Chinese Physics Letters•Jul 16, 2026•0 citations
In the absence of time-reversal symmetry, the asymmetric parameter qqq of the Fano resonance is extended into the complex space, where its trajectory can be utilized to investigate the decoherence process. By embedding the ensemble of Mo\ifmmode¨\else¨\fi\stackrel{\ifmmode \ddot{}\else \"{}\fi{}}{\mathrm{o}}o\ifmmode¨\else¨\fissbauer nuclei in the thin-film planar cavity in this work, the trajectories of asymmetric parameter qqq are studied via the collective effect of the nuclear ensemble, which is regulated by the nuclear abundance and angle offset. Due to the diverse controllable methods of the collective resonant strength, there are different straight lines and arc-shaped trajectories in the complex plane, in which the slopes and the radius can be adjusted by the angle offset and nuclear abundance, respectively. It is demonstrated that the dissipation process can be ``suppressed'' equivalently by the strong energy exchange between the cavity and the nuclear ensemble. The present results could enrich the behaviors of the asymmetric parameter qqq in the complex plane and would provide a new opportunity for decoherence research through the thin-film planar cavity.
In the absence of time-reversal symmetry, the asymmetric parameter q of the Fano resonance is extended into the complex space, where its trajectory can be utilized to investigate the decoherence process. By embedding the ensemble of Mo¨\ddot{\rm{o}}o¨ssbauer nuclei in the thin-film planar cavity in this work, the trajectories of asymmetric parameter q are studied via the collective effect of the nuclear ensemble, which is regulated by the nuclear abundance and angle offset. Due to the diverse controllable methods of the collective resonant strength, there are different straight lines and arc-shape trajectories in the complex plane, in which the slopes and the radius can be respectively adjusted by the angle offset and nuclear abundance. It is demonstrated that the dissipation process can be suppressed equivalently by the strong energy exchange between the cavity and nuclear ensemble. The present results could enrich the behaviors of the asymmetric parameter q in the complex plane and would provide new possibility for the decoherence research through the thin-film planar cavity.
The thin-film planar cavity implanted in the $\mathrm{M}\stackrel{\ifmmode \ddot{}\else \"{}\fi{}}{\mathrm{o}}\mathrm{ssbauer}$ nuclei has been developed as a powerful platform to study the light-matter interaction in the x-ray band. Herein the asymmetric and symmetric profiles of Fano interference are studied by controlling the collective effect and modifying the cavity structure. It is found that the asymmetric profiles in the overcritical and undercritical regimes are the Fano-Lorentz shape, and the asymmetry of the profile is determined by $\mathrm{cos}\ensuremath{\varphi}$ rather than $\mathrm{cot}\ensuremath{\varphi}$ in the framework of the initial Fano theory with $\ensuremath{\varphi}$ being the phase shift of the continuum. In addition, the Fano-Lorentz profile not only can be controlled by the phase difference of the two pathways, but also can be adjusted by the weight of the normal Fano resonance in the Fano-Lorentz profile through regulating the collective effect of the nuclear ensemble. By varying the nuclear abundance at the cavity mode angle, the transformation between the symmetric peak and valley is observed in the overcritical regime, whereas the symmetric peaks are always presented in the undercritical regime. Furthermore, a particularly interesting phenomenon of a flat reflectivity, as if the resonant nuclear ensemble is not excited, is predicted in the nuclear ensemble at a critical nuclear abundance in the overcritical regime. The present results will not only confirm the presence of the complex qqq, but also open up an avenue to study the decoherence processes via the Fano-Lorentz shape in the thin-film planar cavity.
We investigate the effect of decoherence on Fano resonances in wave transmission through resonant scattering structures. We show that the Fano asymmetry parameter q follows, as a function of the strength of decoherence, trajectories in the complex plane that reveal detailed information on the underlying decoherence process. Dissipation and unitary dephasing give rise to manifestly different trajectories. Our predictions are successfully tested against microwave experiments using metal cavities with different absorption coefficients and against previously published data on transport through quantum dots. These results open up new possibilities for studying the effect of decoherence in a wide array of physical systems where Fano resonances are present.
The setting of M\"ossbauer nuclei embedded in thin-film cavities has facilitated an aspiring platform for x-ray quantum optics as shown in several recent experiments. Here, we generalize the theoretical model of this platform that we developed earlier [Phys. Rev. A 88, 043828 (2013)]. The theory description is extended to cover multiple nuclear ensembles and multiple modes in the cavity. While the extensions separately do not lead to qualitatively new features, their combination gives rise to cooperative effects between the different nuclear ensembles and distinct spectral signatures in the observables. A related experiment by R\"ohlsberger et al. [Nature (London) 482, 199 (2012)] is successfully modeled, the scalings derived with semiclassical methods are reproduced, and a microscopic understanding of the setting is obtained with our quantum mechanical description.
In this thesis thin-film cavities with embedded Mössbauer nuclei probed by near-resonant x-ray light are studied from a quantum optical perspective. A theoretical framework is developed and compact expressions for the observables are derived for the linear excitation regime, which is encountered in current experiments. Even advanced cavity layouts can be modeled in excellent agreement with the results of previous experiments and semi-classical approaches. In the absence of magnetic hyperfine splitting, the spectral response of the system is found to be formed by tunable Fano profiles. An experimental implementation of this line shape control allows to extract spectroscopic signatures with high precision and to reconstruct the phase of the nuclear transition in good agreement with the theoretical predictions. The alignment of medium magnetization and polarization control of the x-rays enable to engineer advanced quantum optical level schemes, in which vacuum induced coherence effects are predicted and successfully demonstrated in an experiment. Furthermore, it is shown that group velocity control for x-ray pulses can be achieved in the cavity. A scheme for its observation is proposed and then employed to experimentally confirm sub-luminal x-ray propagation. Finally, non-linear effects, which could become accessible with future light sources, are explored and a non-linear line shape control mechanism is discussed.
Abstract Mössbauer nuclei with quadrupole-split levels provide a versatile platform for exploring coherent x-ray light-matter interactions. We theoretically study ensembles of 57 Fe nuclei embedded in thin-film x-ray cavities, explicitly accounting for different orientations of the electric field gradient. By mapping isotropic electric field gradient distributions to an effective equal-weight two-transition model, we derive analytical expressions for the time-dependent reflectivity and reveal the emergence of cavity-mediated quantum beats. The oscillation frequency and temporal profile of these beats can be tuned via the cavity-induced coherent coupling, offering a flexible approach to control collective nuclear dynamics and manipulate nuclear coherence in the x-ray regime.