arXiv subjects

Eliran Talker

Publications and source records attributed to Eliran Talker.

11 recordsLinked to original sources

arXiv2026

Engineering Near-Infrared Two-Level Systems in Confined Alkali Vapors

We combined experimental and theoretical investigations of an effective two-level atomic system operating in the near-infrared telecom wavelength regime, realized using hot rubidium vapor confined within a sub-micron-thick cell. In this strongly confined geometry, atomic coherence is profoundly influenced by wall-induced relaxation arising from frequent atom-surface collisions. By analyzing both absorption and fluorescence spectra, we demonstrate that the optical response is dominated by a closed cycling transition, which effectively isolates the atomic dynamics to a two-level configuration despite the presence of multiple hyperfine states. This confinement-induced selection suppresses optical pumping into uncoupled states and enables robust, controllable light-matter interaction at telecom wavelengths within a miniature atomic platform. Our results establish a practical route to realizing near-infrared atomic two-level systems in compact vapor-cell devices, opening new opportunities for integrated quantum photonic technologies, including on-chip quantum memories, telecom-band frequency references, and scalable quantum information processing.

quant-ph↗

arXiv2026

Ultra Compact low cost two mode squeezed light source

Quantum-correlated states of light, such as squeezed states, constitute a fundamental resource for quantum technologies, enabling enhanced performance in quantum metrology, quantum information processing, and quantum communications. The practical deployment of such technologies requires squeezed-light sources that are compact, efficient, low-cost, and robust. Here we report a compact narrowband source of two-mode squeezed light at 795 nm based on four-wave mixing in hot 85Rb atomic vapor. The source is implemented in a small, modular architecture featuring a single fiber-coupled input, an electro-optic phase modulator combined with a single Fabry-Perot etalon for probe generation, and two free-space output modes corresponding to the signal and conjugate fields. Optimized for low pump power, the system achieves up to -8 dB of intensity-difference squeezing at an analysis frequency of 0.8 MHz with a pump power of only 300 mW. The intrinsic narrowband character of the generated quantum states makes this source particularly well suited for atomic-based quantum sensing and quantum networking, including interfaces with atomic quantum memories. Our results establish a versatile and portable platform for low-SWaP squeezed-light generation, paving the way toward deployable quantum-enhanced technologies.

quant-ph↗

arXiv2025

Cavity-Free $Δ$-Type Coherent Population Trapping for Microwave Sensing

We investigated experimentally and theoretically a cavity-free microwave field that couples the two ground states of a Λ-type atomic system, thereby forming a closed Δ configuration. In this regime, the absence of cavity-imposed phase matching leads to a strong sensitivity of the ground-state coherence to the microwave field parameters. We observe that the coherent population trapping (CPT) resonance exhibits a pronounced dependence on the microwave power and detuning, resulting in measurable changes in resonance contrast, linewidth, and center frequency. To explain these effects, we develop a numerical density-matrix model in which the ground-state coherence explicitly incorporates the microwave coupling strength, capturing the essential physics of this no-phase-matching Δ system. The excellent agreement between theory and experiment establishes a simple and robust framework for microwave control of cavity-free Δ-type atomic systems, with direct implications for compact atomic clocks and quantum-enhanced quantum sensing platforms.

quant-ph↗

arXiv2025

Beyond Maxwell-Boltzmann statistics using confined vapor cells

Coherence time of thermal photons in rubidium vapor cells with varying thicknesses, reveal that there is clear dependence of the photon correlation time on cell thickness. Standard theoretical models accurately predict the coherence time in centimeter-scale cells. In this study we demonstrated, that these models break down in micrometer and sub-micrometer regimes. Cell sizes ranging from mm-scale down to 200 nm did not adhere to prediction based on the standard models. In order to address this shortcoming, we develop an alternative approach better suited for estimating photonic coherence times in ultra-thin vapor cells. This work, highlights the need for a modified theoretical treatment of the coherence time in the nanoscale regime.

physics.optics↗

arXiv2025

Detuning Tunable OAM Generation via Double-$Λ$ Four-Wave Mixing in Hot Rubidium Vapor

We demonstrate detuning-tunable generation of orbital-angular-momentum (OAM) light using a double Lambda four-wave-mixing (FWM) process in Doppler broadened rubidium vapor. Two near-resonant pumps on the D1 line drive non degenerate FWM that produces bright probe conjugate beams whose transverse modes evolve with pump detuning. A paraxial density-matrix model coupled to split-step propagation predicts detuning-dependent spatial gain shaping that sets the OAM content; experiments with a mode cleaned pump laser and a 12-mm AR-coated vapor cell validate these predictions. We quantify mode formation by imaging, spectroscopy, and power measurements, and verify OAM conservation between the generated beams. The results establish resonant atomic vapor as a compact, tunable platform for structured-light generation with applications to high-dimensional quantum communications and imaging.

physics.optics↗

arXiv2025

Vacuum squeezing enhanced micrometer scale vapor cell magnetometer

We report on an optical magnetometer enhanced by vacuum-squeezed light, employing an Mx magnetometer based on $^{87}$Rb vapor in a micrometer-scale cell (~100 $μ$m). Using the well-established polarization self-rotation effect in a room-temperature $^{87}$Rb vapor cell, we achieve -3 dB of vacuum squeezing within the noise spectral window of 100 Hz to several MHz, corresponding to 3.5 dB squeezing when accounting for optical losses. Leveraging this level of squeezing, we demonstrate a magnetic field sensitivity of approx. 1 pT$/$$\sqrt{Hz}$. The combination of vacuum-squeezed light and micrometer-scale vapor cells paves the way for compact, low-power-consumption atomic sensors with enhanced performance.

physics.optics↗

arXiv2025

Faraday-Ramsey rotation measurement in a thin cell as an analogy to an atomic beam

Atomic beams are powerful tools for measuring spin coherence in hot vapors but require bulky setups, limiting device miniaturization. We demonstrate that micron-thin vapor cells can mimic atomic beam behavior by exploiting geometry-dependent velocity filtering. In a 5 μm rubidium cell, coherence is preserved for atoms moving parallel to the cell walls, enabling observation of the Faraday-Ramsey effect without buffer gas or anti-relaxation coatings. Using a spatially displaced pump-probe scheme and magnetic field scanning, we achieve clear Ramsey fringes and validate our model experimentally. This technique offers a compact alternative to atomic beam systems, supporting scalable sensors and frequency standards.

quant-ph↗

arXiv2023

Remote Chip-Scale Quantum Sensing of Magnetic Fields

Quantum sensing is an ever-evolving research field describing the use of a quantum phenomenon to perform measurement of a physical quantity. Amongst different types of quantum sensors, atomic vapor-based quantum effects are extensively used to measure quantities such as time, velocity, acceleration, and electric and magnetic fields. Here, we propose and demonstrate remote quantum sensing using a chip-scale atomic vapor cell. Specifically, we remotely interrogate mm-scale micromachined vapor cells, and measure the ambient Earth's magnetic field at a standoff distance of ~10 meters and a sensitivity of ~1 pT/Hz^0.5 . Simultaneously we are able measure the distance between micro-cell and the interrogating system by means of time-of-flight measurements, thus correlating between position and magnetic field. Consequently, we provide a novel toolset to measure and map arbitrary, remote, and hard to access magnetic field in unshielded environments with high sensitivity and spatial resolution, paving the way to a variety of novel applications in diverse fields such as medicine, communication, defense, space-exploration, and quantum technologies.

physics.atom-ph↗

arXiv2022

Inversionless gain in a lossy medium

We study gain without inversion due to coherence effects in a Doppler-broadened degenerate three-level system of a rubidium-hydrogen mixture in a miniaturized micron scale custom vapor cell. The cell miniaturization gives rise to collisions of atoms with the walls of the cell. This, combined with the high collision rate with the hydrogen buffer gas allows us to observe gain in the absorption spectra. Furthermore, we analyze the role of cell miniaturization in the evolution of the gain profile. In addition to fundamental interest, the observation of gain without inversion in our miniaturized cells paves the way for applications such as miniaturized lasers without inversion.

quant-ph↗

arXiv2021

Chiral light-matter interactions in hot vapor cladded waveguides

Recently, there is growing interest in integrating alkali vapors with nanoscale photonic structures, such as nano-waveguides, resonators and nanoantennas. Nanoscale confinement of electromagnetic fields may introduce a longitudinal electric field component, giving rise to circularly polarized modes which are essential for diverse applications involving vapor and light, such as chirality and non-reciprocity. Hereby, we have designed, fabricated and characterized a miniaturized vapor cell that is integrated with optical waveguides that are designed to generate a peculiar circular-like polarization. Taking advantage of this phenomenon, we demonstrate a spectral shift in the atomic absorption signatures at varying magnetic fields, and significant isolation between forward and backward propagating waves in our atomic-cladded waveguide. Our results pave the way for the utilization of chip-scale integrated atomic devices in applications such as optical isolation and high spatial resolution magnetometry.

physics.optics↗

arXiv2018

Efficient optical pumping of alkaline atoms for evanescent fields at dielectric-vapor interfaces

We experimentally demonstrate hyperfine optical pumping of rubidium atoms probed by an evanescent electromagnetic field at a dielectric-vapor interface. This light-atom interaction at the nanoscale is investigated using a right angle prism integrated with a vapor cell and excited by evanescent wave under total internal reflection. An efficient hyperfine optical pumping, leading to a complete suppression of absorption on the probed evanescent signal, is observed when a pump laser beam is sent at normal incidence to the interface. In contrast, when the pump and probe beams are co-propagating in the integrated prism-vapor cell, no clear evidence of optical pumping is observed. The experimental results are supported by a detailed model based on optical Bloch equation of a four atomic levels structure. The obtained on-chip highly efficient optical pumping at the nanoscale is regarded as an important step in the quest for applications such as optical switching, magnetometry and quantum memory.

quant-ph↗