- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Single-photon superradiance in waveguide-quantum-electrodynamical systems with whispering-gallery-mode resonators
摘要： As a manifestation of cooperative interactions between a single photon and a cluster of atoms, single-photon superradiance has attracted considerable attention recently but has been studied insofar as that only quantum emitters are involved in the superradiance process. Here we expand the scope of investigation to study single-photon superradiance in a waveguide-quantum-electrodynamical system containing whispering-gallery-mode (WGM) resonators which are essential for many nanophotonic devices. It is shown analytically and numerically that single-photon superradiance can also occur when WGM resonators are present. The criteria for the emergence of the superradiant emission peak and the enhanced atom-light coupling strength are derived. Finally, the general case of a cascade of WGM resonators is investigated by a renormalization approach. Single-photon frequency comb generation is demonstrated via a frequency-modulated superradiant effective atom in chiral waveguide-quantum-electrodynamical systems with WGM resonators.
关键词： single-photon superradiance,whispering-gallery-mode resonators,atom-light coupling,waveguide-quantum-electrodynamical systems,frequency comb generation
更新于2025-09-23 15:19:57
-
[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Electro-Optic Frequency Comb Generation in Lithium Niobate Whispering Gallery Mode Resonators
摘要： Optical frequency combs (OFCs) are light sources whose spectra consists of equally spaced frequency lines in the optical domain [1]. They have great potential for improving high-capacity data transfer, all-optical atomic clocks, spectroscopy, and high-precision measurements [2]. In contrast to the traditional third-order nonlinearity based OFC generation methods, we present a new approach which is based on second-order non-linear effects in a whispering gallery mode (WGM) resonator made of lithium niobate (LN) [3,4]. Our system is composed of a resonant hybrid structure comprising an optical LN disk resonator and a microwave copper cavity. The hybrid structure enables highly efficient nonlinear mixing of photons. In this scheme, two continuous waves, one in the optical domain ((cid:2033) = 193 THz) and another in the microwave region (Ω = 8.9 GHz) couple within a LN WGM resonator [5]. The second-order non-linearity of LN leads to frequency comb generation via cascaded symmetric sum and difference frequency generation [6]. In our experiment, the optical pump power is coupled into the WGM by using a standard prism coupling method that is based on frustrated total internal reflection (Fig. 1 (a)). The microwave power is coupled using a coaxial probe coupled attached to the 3-D copper cavity specifically designed to have the microwave cavity resonance to be equal to the optical free spectral range of the LN resonator, required for efficient phase matching. In addition, the cavity design also provides a very good spatial overlap between the microwave and optical modes by confining the microwave field to the rim of the LN disk. In our proof-of-concept experimental demonstration we observe a 1.6 THz long frequency comb centred around 193.5 THz more than180 comb lines by using only 20 dBm of microwave power. Compared to previously reported OFCs generation schemes, this method has two major advantages: inherent phase stability, and better power efficiency. The power efficiency when measured in terms of pi-voltage of the modulator is 25 times better than a commercial Thorlabs modulator.
关键词： second-order non-linearity,whispering gallery mode resonators,electro-optic frequency comb generation,Optical frequency combs,lithium niobate
更新于2025-09-12 10:27:22
-
[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Frequency Comb Generation at 2 μm with Electro-Optic Modulators for Spectroscopic Applications
摘要： Mid-infrared (2–20 μm) gas sensing allows the detection of strong molecular absorptions with rather small absorption lengths (≤1 m). Various techniques can perform spectroscopic measurements in the mid-infrared but dual-comb spectroscopy (DCS) is one of the most powerful knowing its precision and real-time abilities [1]. However, setups used to perform DCS are in general complex since they require the phase locking of two independent femtosecond lasers at the known state of the art stability. This particular drawback can be bypassed if the combs are generated with electro-optic modulators (EOM) [2]. However, these equipments operate in the telecommunication wavelengths, generally near 1.55 μm where molecular absorptions are not very intense. Here, we experimentally demonstrate two different techniques of generating frequency combs with EOMs around 2 μm.
关键词： Spectroscopic applications,Frequency comb generation,Mid-infrared,Electro-optic modulators,Dual-comb spectroscopy
更新于2025-09-11 14:15:04
-
[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Soliton Combs Generation Due to Parametric up and Down Conversion in a Microring Resonator with Quadratic Nonlinearity
摘要： Frequency comb generation in microring resonators has been intensively studied in the last decade. Frequency combs have applications in precision measurements and optical signal processing. The discrete nature of whispering gallery modes allows microresonators to be natural candidates for frequency comb generation. However, dispersive effects avoid homogeneous spacing between frequency comb lines and for that reason they need to be balanced. Thus, it is essential to generate optical solitons which are, by definition, a result of a balance between the dispersive and nonlinear properties of a resonator.
关键词： microring resonator,quadratic nonlinearity,soliton combs,frequency comb generation
更新于2025-09-11 14:15:04
-
Microring resonator-based photonic system for terahertz signal generation
摘要： We propose a photonic system based on add–drop microring resonator and mode-locked laser for terahertz (THz) signal generation. A mode-locked laser acts as an input source to the microring resonator. The transfer characteristics of the microring resonator generate Lorentzian shaped pulses at the output ports of the microring resonator. These series of pulses obtained are then investigated in two approaches; in the ?rst approach, the output of the microring resonator is given to a photodetector which generates 33 THz pulses separated by a spacing of 1 THz with a full width at half maximum (FWHM) of 0.15 THz. In the second approach, the output of the microring resonator is given to an optical ?lter to extract a particular frequency component. In this case, a single THz carrier with a FWHM of 0.2618 THz is obtained. The THz frequency components generated by the proposed photonic system can act as carriers for communication between the indoor user and the base station of a pico/femto cell in a 5G environment.
关键词： THz signal generation,Microwave photonics,Microring resonator,Frequency comb generation,Mode-locked laser
更新于2025-09-10 09:29:36