Study of additive manufactured microwave cavities for pulsed optically pumped atomic clock applications
Christoph Affolderbach, Willam Moreno, A.E. Ivanov, T. Debogovic, Matthieu Pellaton, A.K. Skrivervik, E. De Rijk & Gaetano Mileti
| Résumé |
Additive manufacturing (AM) of passive microwave components is of
high interest for the cost-effective and rapid prototyping or
manufacture of devices with complex geometries. Here, we present an
experimental study on the properties of recently demonstrated
microwave resonator cavities manufactured by AM, in view of their
applications to high-performance compact atomic clocks. The
microwave cavities employ a loop-gap geometry using six electrodes.
The critical electrode structures were manufactured monolithically
using two different approaches: Stereolithography (SLA) of a
polymer followed by metal coating and Selective Laser Melting (SLM)
of aluminum. The tested microwave cavities show the desired
TE011-like resonant mode at the Rb clock frequency of
≈6.835 GHz, with a microwave magnetic field highly
parallel to the quantization axis across the vapor cell. When
operated in an atomic clock setup, the measured atomic Rabi
oscillations are comparable to those observed for conventionally
manufactured cavities and indicate a good uniformity of the field
amplitude across the vapor cell. Employing a time-domain Ramsey
scheme on one of the SLA cavities, high-contrast (34%) Ramsey
fringes are observed for the Rb clock transition, along with a
narrow (166 Hz linewidth) central fringe. The measured clock
stability of 2.2 × 10−13 τ−1/2 up to
the integration time of 30 s is comparable to the current
state-of-the-art stabilities of compact vapor-cell clocks based on
conventional microwave cavities and thus demonstrates the
feasibility of the approach. This work was supported by Space Positioning Measures of the Swiss Space Office of the State Secretariat for Education, Research and Innovation of the Swiss Confederation (SERI/SSO), call 2016. The authors also acknowledge support of the Swiss National Science Foundation, Grant Nos. 156621 and 162346, as well as previous support of the European Space Agency (ESA) and the European Metrology Research Programme (EMRP Project IND55-Mclocks). The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union. C.A., W.M., M.P., and G.M. thank C. E. Calosso (INRIM, Italy) for providing and support on the microwave local oscillator and F. Gruet and P. Scherler (both LTF, University of Neuchâtel, Switzerland) for support on the laser source and clock physics package. |
| Mots-clés |
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| Citation | C. Affolderbach, et al., "Study of additive manufactured microwave cavities for pulsed optically pumped atomic clock applications," Applied Physics Letters, vol. 112, p. 1-5, Mar. 2018. |
| Type | Article de périodique (Anglais) |
| Date de publication | 16-3-2018 |
| Nom du périodique | Applied Physics Letters |
| Volume | 112 |
| Numéro | 113502 |
| Pages | 1-5 |
| URL | https://doi.org/10.1063/1.5019444 |