A simplified 461-nm laser system using blue laser diodes and a hollow cathode lamp for laser cooling of Sr

Abstract

We develop a simplified light source at 461 nm for laser cooling of Sr without frequency-doubling crystals but with blue laser diodes. An anti-reflection coated blue laser diode in an external cavity (Littrow) configuration provides an output power of 40 mW at 461 nm. Another blue laser diode is used to amplify the laser power up to 110 mW by injection locking. For frequency stabilization, we demonstrate modulation-free polarization spectroscopy of Sr in a hollow cathode lamp. The simplification of the laser system achieved in this work is of great importance for the construction of transportable optical lattice clocks.

InGaN/GaN Laser Diodes With High Order Notched Gratings

“…To fully exploit many of these application areas there is a requirement for a GaN laser diode with high spectral purity and wavelength selectivity. For example in atomic clocks, where a narrow line width blue laser source can be used to target the atomic cooling transition [3] [4], and in fluorescence spectroscopy for medical diagnostics where one can accurately target the emission wavelength [5].…”

Injection locking of a low cost high power laser diode at 461 nm

“…In future work, the TA SHG pro master laser will be replaced by a home-built ECDL laser in Littrow configuration operating with a Nichia NDB4216E-E laser diode delivering up to 40 mW of laser power, as it has been done by Shimada et al 15 , resulting in a fully low cost system.…”

“…450 nm and 460 nm, to perform spectroscopy on a strontium hollow cathode 15 . Two identical laser diodes were used in this experiment: A first laser diode was forced to operate near the Sr transition wavelength by optical feedback within an extended cavity setup (ECDL).…”

Analytical Solutions of Birefringence and Dichroism Spectroscopy for the Jg = 0 → Je = 1 Transition

“…However, it is possible for the simple transition of J g =0 → J e =1 of the atoms such as 88 Sr or Yb. We note that experimental demonstration of PS using Sr was reported [13,16]. Recently, we reported analytical solutions of the PS spectra for the transition J g =0 → J e =1 using reasonable approximation that the Doppler broadening linewidth is much larger than the natural linewidth of the atoms [17].…”