Enhancement cavity


Tailored to your setup, the enhancement cavity CALDERA can be built for continuous-wave as well as for multi-kW-level average power pulsed operation, serving applications such as the generation of coherent vacuum-/extreme-ultraviolet (XUV) radiation at repetition rates of several 10s of MHz.

Femtosecond enhancement cavity: a MHz-repetition-rate pulse train is coherently coupled to a passive optical resonator via a partially transmitting input coupler, giving rise to a circulating pulse with a power increased by up to a few orders of magnitude.
The intracavity pulse can be focused to a gas target to generate coherent vacuum-/extreme-ultraviolet (XUV) radiation at repetition rates of several 10’s of MHz. Coherent XUV radiation obtained by cavity-enhanced high-harmonic generation combines high pulse repetition rates with high photon energies at high XUV photon flux, and serves a host of time-domain and frequency-domain precision metrology applications [1].

Key Product Features

  • State-of-the-art broadband cavity optics
  • Ready for average powers on the 100-kW level
  • Advanced designs tailored to specific applications
  • Stable operation at repetition rates ≥ 10 MHz


[1] Extreme-ultraviolet frequency combs for precision metrology and attosecond science
I. Pupeza, C. Zhang, M. Högner, J. Ye
Nature Photonics 15, 175 (2021)

[2] High-Flux, Ultrafast Extreme-Ultraviolet Photoemission Spectroscopy at 18.4 MHz Pulse Repetition Rate
T. Saule, S. Heinrich, J. Schötz, N. Lilienfein, M. Högner, O. de Vries, M. Plötner, J. Weitenberg, D. Esser, J. Schulte, P. Rußbüldt, J. Limpert, M. F. Kling, U. Kleineberg, I. Pupeza
Nature Communications 10, 458 (2019)

[3] Megawatt-scale average-power ultrashort pulses in an enhancement cavity
H. Carstens, N. Lilienfein, S. Holzberger, C. Jocher, T. Eidam, J. Limpert, A. Tuennermann, J. Weitenberg, D.C. Yost, A. Alghamdi, Z. Alahmed, A. Azzeer, A. Apolonski, E. Fill, F. Krausz, I. Pupeza
Optics Letters 39, 2595 (2014)