Diode-pumped solid-state (DPSS) and external-cavity diode (ECD) lasers are both ideal candidates for narrow-linewidth applications in the emerging quantum technology market. We will be describing some of the spectral performance differences between DPSS and ECD lasers in a poster presentation at Photonics West 2020.
Due to an increased spontaneous emission factor, the line-shape of ECDLs can broaden by approximately fifty times more than in DPSSLs. This suggests that some of the power is emitted outside of the specified linewidth of these systems. In other words, the application-specific useful power is less in ECDLs than in DPSSLs. This is attributed to power detector spectral bandwidths that are usually a few hundred nanometres wide - most of the noise terms are recorded in the output power specification.
We analysed recently published spectra and demonstrated that, for a standard Nd:YAG DPSS laser, the ratio of the application-specific useful power to the total power (or spectral density contract, s.d.c.) can reach 80%. For ECDLs, this figure can be as low as 25%. This suggests that compared to an ECD laser, a DPSS laser can provide three-times the useful power. The ability of DPSSLs is critical for quantum applications, where a narrow linewidth and high spectral power density are required.
Thank you for your interest and we hope to see you in San Francisco next month!
SPIE Photonics West Conference details: LASE Solid State Lasers XXIX: Technology and Devices - Novel Laser Concepts Session 4 - Poster Sessions (view at spie.org)