Subhertz linewidth diode lasers by stabilization to vibrationally and thermally compensated ultralow-expansion glass Fabry-Pérot cavities

J. Alnis, A. Matveev, N. Kolachevsky, Th. Udem, and T. W. Hänsch
Phys. Rev. A 77, 053809 – Published 12 May 2008

Abstract

We achieved a 0.5 Hz optical beat note linewidth with 0.1Hz/s frequency drift at 972 nm between two external cavity diode lasers independently stabilized to two vertically mounted Fabry-Pérot (FP) reference cavities with a finesse of 400 000. Vertical FP reference cavities are suspended in midplane such that the influence of vertical vibrations to the mirror separation is significantly suppressed. This makes the setup virtually immune for vertical vibrations that are more difficult to isolate than horizontal vibrations. To compensate for thermal drifts the FP spacers are made from ultralow-expansion (ULE) glass which possesses a zero linear expansion coefficient. A design using Peltier elements in vacuum allows operation at an optimal temperature where the quadratic temperature expansion of ULE could be eliminated as well. The measured linear drift of such ULE FP cavity of 63 mHz/s was due to material aging and the residual frequency fluctuations were less than ±20Hz during 16 h of measurement. Some part of the temperature-caused drift is attributed to the thermal expansion of the mirror coatings. Thermally induced fluctuations that cause vibrations of the mirror surfaces limit the stability of our cavity. By comparing two similar laser systems we obtain an Allan instability of 2×1015 between 0.1 and 10 s averaging time, which is close to the theoretical thermal noise limit.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
4 More
  • Received 29 January 2008

DOI:https://doi.org/10.1103/PhysRevA.77.053809

©2008 American Physical Society

Authors & Affiliations

J. Alnis1,*, A. Matveev1,2, N. Kolachevsky1,2, Th. Udem1, and T. W. Hänsch1

  • 1Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, 85748 Garching, Germany
  • 2P.N. Lebedev Physics Institute, Leninsky pr. 53, 119991 Moscow, Russia

  • *FAX: 0049 89 32905200.

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 77, Iss. 5 — May 2008

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review A

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×