Chip-integrated Pockels laser emits 780nm with 1GHz tuning, locked to rubidium D2 line

jwt0625 · x · 2026-10-30

• arXiv paper 2610.37279 demonstrates a hybrid InP/thin-film lithium niobate Pockels laser emitting at 780nm via intracavity second-harmonic generation, with gigahertz-bandwidth electro-optic tuning.
• Key numbers: intrinsic linewidths of 2.7kHz (1560nm) and 9.0kHz (780nm); tuning bandwidth >1GHz at both wavelengths; 6.48GHz mode-hop-free tuning at 780nm enabling direct rubidium D2 spectroscopy. Locking to the D2 line cuts frequency fluctuation std dev from 135MHz to 8MHz.
• Clever trick: the SHG acts as a nonlinear output coupler — under gain saturation, SHG power equals the max output power without SHG, so it "autotunes" to the optimal output coupler config and adapts to any pump power.
• The poster, a photonics practitioner, critiques the E-DBR tunable mirror as clunky with little benefit from single resonance, though conceding it is less sensitive to tuning-voltage noise; notes the intracavity SHG idea is nearly 60 years old.

Original post →

More from Research

• Paper Argues One-Click AI Video Will Break Recommendation Pools, Proposes BoLe System — BreadStudio · 2026-10-30
• PersonaCUABench shows computer-use agents fail real user personas across 74 tasks — Haoming Li · 2026-10-30
• PreView: Training-Free Preprocessor Boosts GUI Grounding via Zoomed Views and Cues — Wenjun Hou · 2026-10-30
• SWE-Verifier: a 4B model lifts coding agents ~1.7pp on SWE-Bench at 9–13% extra cost — radamihalcea · 2026-10-30
• Real citations can still be wrong evidence: the hidden failure mode of AI literature answers — yi111 · 2026-10-30
• BindCraft protein design on an M5 Max MacBook rivals RTX 5090, benchmarks show — AllThingsApx · 2026-10-30

Research channel →