Quantum revival for elastic waves in thin plate

Quantum revival is described as the time-periodic reconstruction of a wave packet initially localized in space and time. This effect is expected in finite-size systems which exhibits commensurable discrete spectrum such as the infinite quantum well. Here, we report on the experimental observation of full and fractional quantum revival for classical waves in a two dimensional cavity. We consider flexural waves propagating in thin plates, as their quadratic dispersion at low frequencies mimics the dispersion relation of quantum systems governed by Schr\"{o}dinger equation. Time-dependent excitation and measurement are performed at ultrasonic frequencies and reveal a periodic reconstruction of the initial elastic wave packet.Comment: submitted to the special issue of EPJ ST in honor of scientific legacy of Roger Maynar

Linear and Non-linear Rabi Oscillations of a Two-Level System Resonantly Coupled to an Anderson-Localized Mode

We use time-domain numerical simulations of a two-dimensional (2D) scattering system to study the interaction of a collection of emitters resonantly coupled to an Anderson-localized mode. For a small electric field intensity, we observe the strong coupling between the emitters and the mode, which is characterized by linear Rabi oscillations. Remarkably, a larger intensity induces non-linear interaction between the emitters and the mode, referred to as the dynamical Stark effect, resulting in non-linear Rabi oscillations. The transition between both regimes is observed and an analytical model is proposed which accurately describes our numerical observations.Comment: 11 pages, 6 figure

Localized Modes in a Finite-Size Open Disordered Microwave Cavity

We present measurements of the spatial intensity distribution of localized modes in a two-dimensional open microwave cavity randomly filled with cylindrical dielectric scatterers. We show that each of these modes displays a range of localization lengths and successfully relate the largest value to the measured leakage rate at the boundary. These results constitute unambiguous signatures of the existence of strongly localized electromagnetic modes in two-dimensionnal open random media

2D tunable all-solid-state random laser in the visible

A two-dimensional (2D) solid-state random laser emitting in the visible is demonstrated, in which optical feedback is provided by a controlled disordered arrangement of air-holes in a dye-doped polymer film. We find an optimal scatterer density for which threshold is minimum and scattering is the strongest. We show that the laser emission can be red-shifted by either decreasing scatterer density or increasing pump area. We show that spatial coherence is easily controlled by varying pump area. Such a 2D random laser provides with a compact on-chip tunable laser source and a unique platform to explore non-Hermitian photonics in the visibleComment: 5 pages, 4 figure

Broadband, Single wavelength, Continuous Spectral Control in a Polymer-Based Solid-State Random Laser

In this paper, we present a study on partially pumped, single wavelength random lasing with tunability controlled by temperature in a solid-state random laser based on DCM (4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran) doped PMMA (polymethyl methacrylate) dye. By carefully shaping the spatial profile of the pump, we achieve low-threshold, single-mode random lasing with excellent rejection of side lobes. Notably, we observe that varying the temperature induces changes in the refractive index of the PMMA-DCM layer, resulting in a blue-shift of the lasing wavelength. Moreover, we demonstrate continuous tunability of the lasing wavelength over an impressive bandwidth of 8 nm.Comment: 7 pages, 4 figur

Optofluidic random laser

An active disordered medium able to lase is called a random laser (RL). We demonstrate random lasing due to inherent disorder in a dye circulated structured microfluidic channel. We consistently observe RL modes which are varied by changing the pumping conditions. Potential applications for on-chip sources and sensors are discussed.Comment: 3 pages, 4 figure

Temperature-controlled spectral tuning of a single wavelength polymer-based solid-state random laser

Funding. Engineering and Physical Sciences Research Council (EPSRC[EP/V029975/1]); PICS-ALAMO; Planning and Budgeting Committee of the Council for Higher Education of Israel (2015-2018); United States-Israel Binational Science Foundation (BSF #2022158, NSF/BSF #2015694, NSF/BSF #2021811); Israel Science Foundation (1871/15,2074/15, 2630/20).We demonstrate temperature-controlled spectral tunability of a partially-pumped single-wavelength random laser in a solid-state random laser based on DCM (4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran) doped PMMA (polymethyl methacrylate) dye. By carefully shaping the spatial profile of the pump, we first achieve low-threshold, single-mode random lasing with excellent side lobes rejection. Notably, we show how temperature-induced changes in the refractive index of the PMMA-DCM layer result in a blue shift of this single lasing mode. We demonstrate spectral tunability over an 8nm-wide bandwidth.Publisher PDFPeer reviewe