A miniature frequency-stabilized VCSEL system emitting at 795nm based on LTCC modules

Abstract

a b s t r a c tWe present a compact frequency-stabilized laser system locked to the Rubidium absorption line of a micro-fabricated reference cell. A printed circuit board (PCB) is used to carry all the components and part of the electronics, and low-temperature co-fired ceramic (LTCC) modules are used to temperaturestabilize the laser diode and the miniature Rubidium cell (cell inner dimensions: 5 mm diameter and 2 mm height). The measured frequency stability of the laser, in terms of Allan deviation, is ≤8 Â 10 −10 for integration times of 10 3 -10 5 s. The current overall dimensions of the system are 70 Â 40 Â 50 mm 3 , with good potential for realization of a frequency-stabilized laser module with few cm 3 volume.

Chip-scale atomic devices

“…Doppler-free saturated absorption lines were obtained in a compact saturated absorption spectrometer, 278 and the microfabricated alkali vapor cells were used to implement a modulation-free dichroic atomic vapor laser lock. 279,280 VCSELs have been stabilized to optical transitions in a Cs MEMS cell 281 and a stability below 10…”

Meso-scale ceramic hotplates – A playground for high temperature microsystems

“…Given that all "resistors" are in parallel at the LTCC bridges, the R bridge then can be obtained according to Eqs. (5) and (6). As the LTCC hotplate stays at T op = 560-570 • C, the estimated R bridge corresponds to ∼680 K W −1 .…”

“…Heating devices range from millimeters to several centimeters, so-called meso-hotplates, have been widely studied and utilized for many applications: gas and flow sensors [1,2], micro power generators [3][4][5], frequency-stabilized lasers [6], discharge lamps for atomic clocks and magnetometers [7] and microfluidics [3,8,9], just to name a few. Such meso-hotplates typically contain metallic or resistive heaters fabricated on a thermomechanically decoupled area of a dielectric substrate.…”

Exploring Dual-Frequency Sub-Doppler Spectroscopy for a Cs Microcell-Based Optical Frequency Reference

“…This includes the study of Dopplerfree resonances in microfabricated cells [6], the stabilization of VCSELs onto Doppler-broadened resonances [7], the stabilization of a Brillouin scattering laser onto a Rb microcell [8], sub-Doppler spectroscopy technique using an integrated photonic waveguide [9] or the recent photonic integration of a miniaturized optical clock based on detection of the Rb 778 nm two-photon transition in a microfabricated cell [10]. The latter frequency reference exhibits a remarkable frequency instability level of 4.4 × 10 −12 τ −1/2 until 1000 s [10] whereas previous works [7], [8], [9] were often limited at the level of about 10 −11 between 1 s and 10 4 s. Note also excellent frequency noise performances reported by ultralow noise miniaturized external cavity semiconductor laser using whispering-gallery mode optical micro-resonators [11]. In a recent study [12], the detection of high-contrast signreversed natural-linewidth Doppler-free dips in a Cs vapor cell has been reported using dual-frequency sub-Doppler spectroscopy (DF SDS).…”