Weak Probe Field Research Articles

Three-cavity system with multiple magnomechanically induced transparency

This paper presents the characteristics of a weak probe field in a three-connected cavity system. In this system, a microwave cavity contains a yittrium iron garnet sphere that is driven by a strong pump and a weak probe optical fields, and the magnon is driven by a weak microwave source. The other two cavities are empty and are coupled to the first cavity with specific coupling strengths. This setup leads to the observation of multiple magnomechanically induced transparency phenomena by varying quantum parameters g ma, g mb, and the coupling strengths between cavities J 1 and J 2. The study of these phenomena in the three coupled cavities can potentially contribute to advancements in quantum transduction and future technologies.

Phase-modulation-induced reconfigurable rotating photonic lattices in atomic vapors.

We propose a method to prepare optically induced rotating hexagonal and honey-comb photonic lattices by employing the phase modulated three-beam interference in atomic vapors with electromagnetically induced transparency. The phase differences among the three beams are dynamically elaborated to synthesize the circular motion (in transverse dimensions) of waveguides in the photonic lattices. Further, we verify this model experimentally in the case of low-speed modulation. A weak Gaussian probe field is sent into the constructed helical photonic lattices to image their structures under electromagnetically induced transparency (EIT). The motion trajectories of the sites on the discretized output patterns exhibit repeated circles, advocating the formation of rotating lattices. By introducing phase modulations to involved beams, we provide a continent way for producing transverse motions in waveguide arrays with reconfigurability in rotational direction, radius, and speed. This work looks forward to promising applications in topological photonics with great popularity.

Tunable multicolor optomechanically induced transparency and slow-fast light in hybrid electro-optomechanical system

Abstract We investigate the tunable multicolor optomechanically induced transparency and the effect of slow/fast light in a hybrid electro-optomechanical system, in which a degenerate optical parametric amplifier (OPA) and a Λ − type three-level atomic ensemble are placed in a optical cavity with two oscillator modes. The system is driven by a strong pump field and a weak probe field, respectively. Multicolor transparency windows appear in the output field under the atom-photon-OPA-phonon-phonon coherent interaction. And the position and width of the transparent port of the output field can be manipulated by properly modifying the different parameters of the subsystem. We also research the slow/fast light effect related to phase and group delay in the probe field. Our proposal provides a great flexibility for phonon storage and has some potential applications in quantum information processing.

Efficient control of high-precision three-dimensional atom localization via probe absorption in a five-level phase-coherent atomic system

We propose a new scheme for high-precision three-dimensional (3D) atom localization by observing the spatially modulated absorption of a weak probe field operating in a partially closed-loop dependent five-level atomic system. Different spatial structures of localization patterns are presented by controlling the Rabi frequency, detuning, and field-induced collective phase-coherence with a variety of superposed standing wave field configurations. Our results highlight that 100% detection probability of atom is possible in the present model in many ways with high precision measurement of spatial absorption. It has been shown that, in the presence of standing wave fields, position information of the atom with maximum detection probability can be efficiently controlled by employing the travelling-wave field in the system. In the present work, we note that the maximum detection probability of the atom is attainable with the limit of spatial resolution better than λ/50. The efficacy of the present model is to find its application in atom nanolithography and atom-imaging having importance in quantum information processing.

Multiple optomechanically induced transparency generated slow light in an array of optomechanical system

We present an array of optomechanical systems which consist of an optical cavity and three nanomechanical resonators. Introducing Jaynes-Cumming (J-C) coupling in the nearest neighbor resonator allows for the formation of optomechanical systems with arrays of N nanomechanical resonators. Using a strong pump field and a weak probe field to drive the optical cavity simultaneously, we investigated the coherent optical response and the probe transmission spectrum manifested as multiple optomechanically induced transparency. We illustrate the impact of probe-cavity detuning, J-C coupling strength, and the number of nanomechanical resonators on the transparent window. In particular, we analyze nanomechanical resonators and find that increasing their number results in multiple transparent windows and slow light at different frequencies. We also find that the slow light effect can be enhanced by increasing the number of nanomechanical resonators with odd numbers at resonance. These findings imply that the arrays of optomechanical system can be used for multichannel optical communications and multichannel quantum information processing.

Modulation of Second-Order Sideband Efficiency in an Atom-Assisted Optomechanical System

We propose an efficient scheme to enhance the generation of optical second-order sidebands (OSSs) in an atom-assisted optomechanical system. The cavity field is coupled with a strong driving field and a weak probe field, and a control field is applied to the atom. We use the steady-state method to analyze the nonlinear interaction in the system, which is different from the traditional linear analysis method. The existence of an auxiliary three-level atom driven by the control field significantly enhances the generation of an OSS. It is found that the efficiency of the OSS can be effectively modulated by adjusting the Rabi frequency of the control field, optomechanical cooperativity and atomic coupling strength. Our scheme provides a promising solution for controlling light propagation and has potential application in quantum optical devices and quantum information networks.

Vortex beam induced spatial modulation of quantum-optical effects in a coherent atomic medium

We have studied two-dimensional absorption, gain, and corresponding refractive index profiles in a ladder-type three-level atomic system interacting with three coherent fields. One is a weak probe field considered as a plane wave, while the other two are the control fields taken as two Laguerre–Gaussian doughnut beams. Position dependence of two vortex beams induces the spatially modulated coherence at the condition of resonance, which enables us to obtain space-dependent absorption, transparency, gain without inversion (GWI), and refractive index enhancement in the present scheme. The azimuthal modulation of coherence effects is attributed to the presence of optical angular momentum of the vortex beams. Under the influence of an additional travelling wave field with the presence of two vortex beams, the present model leads us to obtain an ultra-large enhancement of refractive index at the resonant detuning of the fields. This phenomenon makes the atom-field system to play the equivalent role of a high-refractive-index prism. The role of near dipole–dipole (NDD) interaction on the modulation of position-dependent coherence effects has also been investigated. It has been shown that, without any inclusion of the travelling wave field in the system, the phenomenon of resonant enhancement of refractive index may also occur in the presence of NDD effect. The new way of generating spatially controlled GWI and nonlinear refractive index enhancement is specific to the present model. This work seems to be useful for finding its applications in spatially modulated coherence controlled electromagnetically induced transparency-based quantum devices like quantum optical memory, switches, and quantum logic gates, where the refractive index switching phenomenon is a prerequisite.

Amplified Nonreciprocal Reflection in a Uniform Atomic Medium with the Help of Spontaneous Emissions

It is important to elaborate on versatile strategies for achieving the perfect nonreciprocal reflection amplification, which is the key technology of high-quality nonreciprocal photonic devices. In this work, we ingeniously design a coherent four-level N-type atomic system to harness the nonreciprocal light amplification, in which the uniform distribution of atoms is driven by two strong coupling fields and a weak probe field. In our regime, the strength of the two control fields is designed with linear variation along the x direction to destroy the spatial symmetry of the probe susceptibility, leading to the nonreciprocity of the reflection. In particular, the closed-loop transitions to amplify the probe field are due to the combined effect of the control fields and spontaneous emissions. The numerical simulation indicates that the perfect nonreciprocal reflection amplification can be realized and modulated by the appropriate settings of the control fields and the detuning, Δc. Our results will open a new route toward harnessing nonreciprocity, which can provide more convenience and possibilities in experimental realization.

2D asymmetric diffraction grating controlled by vortex light in double-Λ-type atomic system

A two-dimensional (2D) asymmetric diffraction grating controlled by vortex light in a double-Λ-type atomic system is studied. Such an atomic system is driven by a weak traveling-wave probe field and a signal field, a position-dependent strong standing-wave (SW) control field, and a Laguerre–Gaussian (LG) vortex field. Due to the asymmetric properties of the LG vortex field, the probe photons can be asymmetrically diffracted into four different domains after passing through the atomic media. The Diffraction patterns and intensities of the 2D asymmetric diffraction grating can be manipulated by the detuning of the probe field, the interaction length, and the intensity of SW control field. In addition, the relative phase and the azimuth parameter which is closely related to the vortex light also can be used to regulate the asymmetric diffraction grating effectively. This work may provide useful reference for optical information processing, especially for the design of optical beam dividers with desired intensities and novel quantum devices requiring asymmetric optical transmission.

Photothermally and optomechanically induced transparency in a hybrid optomechanical system

AbstractWe theoretically investigated the photothermally and optomechanically induced transparency (PTIT and OMIT) in an optomechanical system filled with quantum dots (QDs). In our proposed system, the right mechanical resonator couples with the optical cavity via radiation pressure, and the left mechanical resonator couples with the optical cavity through the photothermal effects. The system is driven by a strong pump field and a weak probe field. It is shown that double transparency windows can be observed due to PTIT and OMIT. When considering the Jaynes‐Cummings coupling between the QDs and the optical cavity, three transparency windows are observed. We also show that the PTIT can be adjusted by the OMIT and the QDs in the optical cavity. What is more, the coupling strength and the frequency detuning can be used effectively to change the system absorption and dispersion in the PITT transparency window. This indicates that the group delay of the probe light can also be manipulated by the system parameters. The obtained results may be applied in the optical communication such as optical buffer, and so forth.

Influence of phase diffusion on atomic grating in a three-level ladder-type system in lower-level microwave-driven scheme

In this paper, we consider a scheme for electromagnetically induced grating (EIG) in a three-level ladder-type system. A microwave field of finite bandwidth making a standing-wave pattern is applied on lower levels. In addition, we have also introduced an indirect pump in our system. A weak probe field is then applied to study the effects of phase diffusion associated with the microwave control field on EIG. It is found that phase diffusion associated with the strong microwave control field strongly affect the diffraction. We have incorporated the effect of different system parameters such as the strength of the microwave field, indirect pumping mechanism, interaction length, and detuning in the weak probe field. Interestingly, the stronger microwave control field retrieves the loss in diffraction intensity caused by the phase diffusion. Our results show that the introduction of detuning in the optical probe field results in the enhancement of the phase grating effect. Furthermore, our results show that an optimized indirect pump field can slightly improve the first-order diffraction intensities both in the absence and presence of phase diffusion.

Effect of phase fluctuations on atomic Talbot images in three-level ladder-type atomic system

In this article, we study the atomic Talbot effect in a three-level ladder-type atomic system, which consists of a strong microwave field having a finite bandwidth and a weak probe field. The upper levels are coupled with a strong position-dependent microwave field, while a weak probe field interacts with lower levels of the atomic system. We find that phase fluctuations associated with a strong microwave field significantly affect the transmission and corresponding intensity of Talbot images. We show that the choice of various parameters is crucial in the presence of phase fluctuation. An appropriate choice along with a pump field can still improve the intensity of atomic Talbot images. We believe that our results are useful for any practical situation where the effects of phase fluctuations are important.

Spatial susceptibility modulation and controlled unidirectional reflection amplification via four-wave mixing.

Control of unidirectional light propagation is of paramount importantance to optical signal processing and optical communication. Especially, the amplified optical signal can isolate noise well that may provide more applications. In this work, we propose a dynamically modulated regime to realize unidirectional reflection amplification in a short and dense uniform atomic medium, and all atoms are driven into four-level double-Λ type by two coupling fields with linearly varied intensities along x direction and two weak probe fields. Based on four-wave mixing resonance and the broken spatial symmetry, the complete nonreciprocal reflection (unidirectional reflection) can be amplified with reflectivity more than 2.0, even to 6.0. In addition, the width, height, and position of the unidirectional reflection bands can be tunable. Thus, our regime is feasible and may inspire further applications in all-optical networks that require controllable unidirectional light amplification.

Light drag in a left-handed atomic medium via Cross Kerr-like nonlinearity

In this paper, we investigates the Cross Kerr-like nonlinearity effect on the quantum control of the light drag in a negative refractive index media ( NRI). Hence, we consider an atomic system in a four-level Y-type configuration, where a signal field couples the ground state to an upper level. Another weak probe field drives the intermediate transition to the excited state. The Kerr field pumps the excited state to another higher fourth transition. Therefore, we observe that the third-order optical non-linearities drastically contribute to the light drag enhancement of about 11 times. Interestingly, the light drag dynamics can be manipulated to shift from positive to negative, which allows the group delay and advancement to be fully controlled. Typically, an increase in the Kerr field, simultaneously with the detuning, induces an ultra-narrow, sharp peak in the light drag respectively at the resonance and far from the resonance with a group delay ranging from τ=−0.2 to τ=−2. The various interference pathways of light caused by the cross-kerr along with the probe, strong and signal fields not only enhance the light drag but can also be used to shift the light from subluminal to superluminal propagation under negative refraction. These results provide a framework for utilizing the Kerr-cross non-linearity to control the light drag in NRI, which is interesting in applications such as optical trapping.

A comparative study of electromagnetically induced transparency (EIT) in Λ-, V-, and Ξ-type systems using Laguerre–Gaussian (LG) laser beams

In this paper, a theoretical investigation of electromagnetically induced transparency (EIT) using Laguerre–Gaussian (LG) beams has been carried out for the three canonical atom-laser coupled systems (e.g. [Formula: see text]-, V-, and [Formula: see text]-type) in [Formula: see text]Rb atom. The required optical Bloch equations (OBEs) are derived for each system. The OBEs are analytically solved in steady-state condition under the weak probe field approximation. We have used the iterative perturbative technique to obtain the probe coherence term. The probe response w.r.t. probe detuning for different orders of the orbital angular momentum (OAM) number of both the pump and probe LG beams has been studied. We have also studied the effect of the OAM number on probe response in both Doppler-free and Doppler-broadened mediums. It has been observed that the EIT signal is squeezed for nonzero OAM number of the pump beam with arbitrary OAM number of the probe beam. It is found that for higher-order OAM number, the EIT signal is further squeezed. The modification of the EIT signal is attributed because of the spatial-dependent Rabi frequency. Our study demonstrates that the dynamic of the probe field inside an atomic medium may be controlled by tuning the OAM number of the LG beam.

Control over magneto-optical plasmon rotation with Doppler broadening and cross-Kerr non-linearity

We investigate the impacts of cross-Kerr non-linearity and Doppler broadening on the magneto-optical rotation (MOR) induced in surface plasmon polaritons (SPPs) located at the interface of a metalic medium and a 4-level atomic system. In this paper, the external static magnetic field and a weak probe field under the cross-Kerr effect result in the birefringence enhancement of the system. Moreover, the incoherent effect of Doppler broadening can regulate the MOR of SPPs. Notably, the controlled MOR of SPPs can be leveraged for a variety of advantageous implementations in the fields of polarization spectroscopy, optical communication, nanoscale Faraday isolation, accurate metrology, as well as bio/chem sensing technologies.

Tunable Rydberg–Rydberg transitions in helium with reduced sensitivity to dc electric fields by two-colour microwave dressing

The difference in the static electric dipole polarizabilities of the and Rydberg levels in helium has been eliminated by dressing the atom with a microwave field near resonant with the single-photon transition. For an amplitude dressing field, detuned by from the zero-field transition frequency, the dc Stark shift of the two-photon transition between these states remained within for electric fields up to . This transition was probed by single-color two-photon microwave spectroscopy, and by two-color two-photon spectroscopy with one strong additional dressing field and a weak probe field. For all measurements, the transition frequencies and Stark shifts were compared, and found to be in excellent quantitative agreement with the results of Floquet calculations of the energy-level structure of the Rydberg states in the presence of the dressing fields and applied dc electric fields. The two-color microwave dressing scheme demonstrated, with one field applied to null the differential polarizability of the Rydberg–Rydberg transition, and the second exploited to allow the two-photon transition to be employed to achieve tunable absorption of single-photons from a weak probe field, will facilitate improved coherence times and tunable single-photon absorption in hybrid cavity QED experiments with Rydberg atoms and superconducting microwave circuits.

Investigation of diffraction grating in photothermal cavity

The photothermal effects in an optical cavity driven by a strong control field and a weak probe field have recently been shown to generate an induced transparency phenomenon (Ma et al., 2020). This phenomenon, referred to as photothermally induced transparency (PTIT), arises from the nonlinear behavior of an optical resonator caused by optical heating of the its mirrors. In this study, we investigate the manipulation of PTIT by substituting the strong coupling field in the PTIT scheme with a spatially periodic standing wave (SW) coupling field, resulting in the diffraction of the weak probe field into high-order diffractions. The resulting structure, termed the photothermally induced grating (PTIG), can be effectively controlled by adjusting various system parameters, including the coupling strength, effective detuning, interaction length, and photothermal coefficient. By carefully optimizing the coupling strength, we demonstrate that a significant portion of the probe field energy can be efficiently transferred to the third-order diffraction grating. The introduction of a spatially periodic standing wave coupling field opens up new possibilities for designing and manipulating photothermally induced gratings with enhanced functionalities.

Operating mode dependent energy transfer efficiency in a quantum well waveguide

In this paper, we delve into the intricate interplay between optical fields with varying relative phases in a closed-loop configuration semiconductor quantum well waveguide with four distinct energy levels, and how it impacts the Fraunhofer diffraction patterns obtained via four-wave mixing. By harnessing a strong control field, a standing wave driving field, and two weak probe and signal fields, we drive the waveguide to generate these patterns with maximum efficiency. To achieve this, we consider three distinct light-matter interaction scenarios, where the system is first set up in either a lower electromagnetically induced transparency or a coherent population trapping state, followed by a final state that enables electron spin coherence (ESC) induction. Our results reveal that the efficiency of Fraunhofer diffraction in the quantum well waveguide can be enhanced significantly under specific parameter regimes via the spin coherence effect. Further investigation of the light-matter interaction in the ESC zone, where only one of the control fields is a standing wave field, demonstrates that spin coherence facilitates more efficient transfer of energy from the probe light to the third and fourth orders, highlighting its crucial role in shaping the diffraction patterns.

Surface Plasmon Polaritions via Squeezed Vacuum States

This paper investigates a dielectric under a squeezed vacuum state, a thermal field and a normal vacuum state. The dielectric atoms are considered in a three-level lambda type configuration, where a weak probe field induces and generates surface plasmon polaritons (SPPs) at the silver and dielectric interface. Therefore, to get deeper insights into the dispersion and absorption spectra, the propagation length and the skin depth, we investigate the system’s coherence. Hence, we demonstrate that the strong laser used to couple the intermediate level to the upper excited state drastically affects the generated SPPs wavelength at the interface. Additionally, the system properties are fully controlled by the average photon number, the thermal field, the normal vacuum and the squeezed vacuum state. Finally, in an attempt to elaborate a straightforward technique that manipulates the Lsp ( surface plasmon length ) distance we control the system by simultaneously tuning the phase and the control field in a particular detuning region. Our results might be of great interest to the engineering of miniature nano-photonic devices and circuits requiring sub-wavelength property.