Atom–Photon Interactions in Atomic Cladded Waveguides: Bridging Atomic and Telecom Technologies

Abstract

Accurate and stable frequency sources can be realized by locking lasers to well-known transitions between energy levels in isolated quantum systems such as alkali atoms. Unfortunately, current implementations of such frequency standards typically involve bulky optical setups and discrete optical components. Furthermore, the common transitions of alkali atoms are in the near-infrared, hindering their use as frequency references in the telecom regime. Our current work is focused on mitigating these deficiencies. In particular, we demonstrate the design, fabrication, and experimental characterization of an on-chip telecom frequency reference that is based on a ladder transition of rubidium atoms integrated with nanoscale optical waveguides. These atomic cladded waveguides are implemented in a serpentine geometry in order to optimize the chip area and maximize the interaction of light with the alkali atoms. Following its fabrication, the device is used to stabilize a telecom laser around a 1.5 μm wavelength to a precision better than 200 kHz at ∼250 s. Moreover, in spite of the fact that the natural lifetime of the excited state of the atom corresponding to only a few megahertz line widths, the nanoscale confinement of the optical mode dictates ultrashort interaction times and extreme photonic energy densities allowing us to demonstrate low power and faster (∼200 MHz) all-optical modulation of a near-infrared light with a telecom light. The results presented in this paper push forward the efforts toward fully integrated chip-scale stabilization system and provide an extremely efficient link between atomic based devices and silicon photonics platform in the telecom.

On‐Chip Light–Atom Interactions: Physics and Applications

“…The device has realized cost-effective, miniaturized, and low-power optical frequency references in the telecommunications C band and can be used for 1.5 μm laser frequency stabilization. [109] Analogously, a previous study research has shown that cladding [108] Copyright 2015, AIP. (c,d) Reproduced with permission.…”

“…We review four types of nanostructures, namely optical waveguide, photonic crystal, metasurface, and microcavity to demonstrate the main achievements and progress in light-atom interactions affected by these nano-structures and their corresponding applications (see Table 1). Waveguide strip evanescent coupling, [108] circular birefringence [30,62] alkali atom spectroscopy, [108] optical isolators, [62] magnetometers, [62] magneto-optic modulators, [30,62,110] optical memories, [62] frequency stabilization, [30,62,110] detectors [30] slot Casimir-Polder interactions [63] atomic clocks, [63] dipole-dipole interactions [63] photonic crystal Casimir-Polder effect, [63] photon-mediated interactions, [114] atom-atom radiative interactions, [97,113] Purcell effect [24] cold atoms trapping, [97,113,114] optical tweezers [114] serpentine evanescent interactions [30,62,109] all-optical modulator, [109] all-optical switching, [109] frequency reference, [109] frequency stabilization, [30,62] lidar, [30] optical isolators, [62] field sensors, [62] magneto-optic modulators, [30,62] optical memories, [62] detectors...…”

“…The device has realized cost‐effective, miniaturized, and low‐power optical frequency references in the telecommunications C band and can be used for laser frequency stabilization. [ 109 ] Analogously, a previous study research has shown that cladding waveguides with other material for light–matter interactions such as acetylene molecule cladding waveguide (MCWG) could be used for frequency reference and stabilization using the same structure. [ 30 ] Both ACWGs and MCWGs are designed with the same serpentine geometry to decrease the chip area and enlarge the area for light–atom interactions.…”

MoSe2/WS2 heterojunction photodiode integrated with a silicon nitride waveguide for near infrared light detection with high responsivity

“…Examples of this can be seen in the burgeoning field of nanoscale atom–light interactions. Here, hot vapors of atomic gasses, like rubidium or cesium are interfaced together with integrated photonic components, such as atomic cladded waveguides (ACWGs) 42 – 46 , resonators 47 , 48 , and surface plasmons 49 – 51 , to create novel chip-scale atomic devices. Likewise, integrating biological samples with photonic circuits can enable new and interesting applications 52 , 53 .…”

Integrated Polarization-Splitting Grating Coupler for Chip-Scale Atomic Magnetometer

“…Numerous industrial platforms have been developed in the past few years to facilitate the fabrication of integrated photonics devices. Therefore, it is promising to achieve complete chip integration of atomic devices through emerging integrated photonics and CMOS-compatible nanofabrication technology [ 23 , 24 , 25 ], which promotes both drastic miniaturization and mass production.…”