Nonlocal stabilization of nonlinear beams in a self-focusing atomic vapor

Stabilization of dipole solitons in nonlocal nonlinear media

We address the stabilization of dipole solitons in nonlocal nonlinear materials by two different approaches. First, we study the properties of such solitons in thermal nonlinear media, where the refractive index landscapes induced by laser beams strongly depend on the boundary conditions and on the sample geometry. We show how the sample geometry impacts the stability of higher-order solitons in thermal nonlinear media and reveal that dipole solitons can be made dynami-cally stable in rectangular geometries in contrast to their counterparts in thermal samples with square cross-section. Second,…

Collapse suppression and stabilization of dipole solitons in two-dimensional media with anisotropic semi-local nonlinearity

We consider the impact of anisotropic nonlocality on the arrest of the collapse and stabilization of dipole-mode (DM) solitons in two-dimensional (2D) models of optical media with the diffusive nonlinearity. The nonlocal nonlinearity is made anisotropic through elliptic diffusivity. The medium becomes semi-local in the limit case of 1D diffusivity. Families of fundamental and DM solitons are found by means of the variational approximation (VA) and in a numerical form. We demonstrate that the collapse of 2D beams is arrested even in the semi-local system. The anisotropic nonlocality readily sta…

Vapor-cell frequency reference for short-wavelength transitions in neutral calcium

We have characterized the molecular tellurium (Te$_2$) spectrum in the vicinity of the 423nm $^1S_0-^1P_1$ and the 431nm $^3P_1-^3P_0$ transitions in neutral calcium. These transitions are relevant to optical clocks for atomic-beam characterization and cooling (423nm) and enhanced detection (431nm). The use of a Te$_2$ vapor cell as a frequency reference has many advantages over other laser stabilization techniques, and we discuss an application to measuring the instability due to the second-order Doppler shift in a calcium beam clock.

通过钾蒸汽中可交换的激发路径实现多普勒辅助的量子共振

Doppler-assisted quantum resonances through swappable excitation pathways in Potassium vapor

本文报告了在$^{39}K$蒸汽中因多普勒效应导致激发路径交换而观察到的亚自然线宽量子干涉现象，通过主方程绝热消除解释了透明到吸收的转换，为激光稳频和量子存储提供了新应用。

Evanescent light-matter Interactions in Atomic Cladding Wave Guides

Alkali vapors, and in particular rubidium, are being used extensively in several important fields of research such as slow and stored light non-linear optics3 and quantum computation. Additionally, the technology of alkali vapors plays a major role in realizing myriad industrial applications including for example atomic clocks magentometers8 and optical frequency stabilization. Lately, there is a growing effort towards miniaturizing traditional centimeter-size alkali vapor cells. Owing to the significant reduction in device dimensions, light matter interactions are greatly enhanced, enabling n…

Multipole vector solitons in nonlocal nonlinear media

We show that multipole solitons can be made stable via vectorial coupling in bulk nonlocal nonlinear media. Such vector solitons are composed of mutually incoherent nodeless and multipole components jointly inducing a nonlinear refractive index profile. We found that stabilization of the otherwise highly unstable multipoles occurs below a maximum energy flow. Such threshold is determined by the nonlocality degree.

基于芯片级原子衍射元件的激光偏移稳频

Laser Offset Stabilization with Chip-Scale Atomic Diffractive Elements

本研究利用微加工原子衍射元件蒸气室的相衬光谱实现激光偏移稳频，在数十吉赫兹带宽内提供多个稳频点，达到亚兆赫兹级不稳定性，器件紧凑且可芯片级量产，适用于量子技术等领域。

Self-organization of light in optical media with competing nonlinearities

We study the propagation of light beams through optical media with competing nonlocal nonlinearities. We demonstrate that the nonlocality of competing focusing and defocusing nonlinearities gives rise to self-organization and stationary states with stable hexagonal intensity patterns, akin to transverse crystals of light filaments. Signatures of this long-range ordering are shown to be observable in the propagation of light in optical waveguides and even in free space. We consider a specific form of the nonlinear response that arises in atomic vapor upon proper light coupling. Yet, the general…

利用介质光学超表面芯片定制热原子的亚多普勒光谱

Tailoring sub-Doppler spectra of thermal atoms with a dielectric optical metasurface chip

本研究针对铷原子蒸气设计集成纳米光栅超表面的微型蒸气池，搭建泵浦-探测光谱系统，实现低功率亚多普勒响应观测、偏振调控谱形及高稳定度激光稳频，为原子光谱调控提供新方案。

Atomic line versus lens cavity filters: A comparison of their merits

We present a comparison between lens cavity filters and atomic line filters, discussing their relative merits for applications in quantum optics. We describe the design, characterization and stabilization procedure of a lens cavity filter, which consists of a high-reflection coated commercially available plano-convex lens, and compare it to an ultra-narrow atomic band-pass filter utilizing the D$_{2}$ absorption line in atomic rubidium vapor. We find that the cavity filter peak transmission frequency and bandwidth can be chosen arbitrarily but the transmission frequency is subject to thermal d…

一种频率稳定度低于10⁻¹⁵的脉冲光抽运铷钟

A pulsed optically pumped Rb clock with a frequency stability below 10-15

INRIM与Leonardo SpA合作开发航天级脉冲光抽运汽室铷钟，采用工程化物理包结合实验室级光电设备，实现1秒稳定度1.2×10⁻¹³、40000秒（去漂）6×10⁻¹⁶的创纪录结果，需精细稳定微波和激光脉冲。

集成微环谐振器与碱金属原子蒸气之间的强相互作用：迈向单原子、单光子操作

Strong interactions between integrated microresonators and alkali atomic vapors: towards single-atom, single-photon operation

本文研究原子包覆微环谐振器与铷原子系综的腔量子电动力学相互作用，在约50个原子下实现强耦合（协同度约5.5），并在少数原子下观察到单光子水平饱和，为迈向单原子-单光子操作提供了可部署的集成平台。