Linear field-resolved spectroscopy approaching ultimate detection sensitivity
Year of publicationPublished in:Optics Express
C. Hofer, D. Bausch, L. Fürst, Z. Wei, M. Högner, T. Butler, M. Gebhardt, T. Heuermann, C. Gaida, K. Maiti, M. Huber, E. Fill, J. Limpert, F. Krausz, N. Karpowicz, I. Pupeza
Electric-field oscillations are now experimentally accessible in the THz-to-PHz frequency range. Their measurement delivers the most comprehensive information content attainable by optical spectroscopy – if performed with high sensitivity. Yet, the trade-off between bandwidth and efficiency associated with the nonlinear mixing necessary for field sampling has so far strongly restricted sensitivity in applications such as field-resolved spectroscopy of molecular vibrations. Here, we demonstrate electric-field sampling of octave-spanning mid-infrared waves in the 18-to-39 THz (600-to-1300 cm−¹) spectral region, with amplitudes ranging from the MV/cm level down to a few mV/cm. We show that employing powerful 2-µm gate pulses is key to approaching the ultimate detection limit of capturing all photons in the temporal gate, as well as providing high linearity with respect to the detected mid-infrared field. This combination of detection sensitivity, dynamic range, and linearity enables the exploitation of the full potential of emerging high-power waveform-controlled infrared sources for (non-)linear spectroscopy of solids, liquids, and gases.
18-mJ pulse energy, 27-W average power, second harmonic generation in a Q-switched 49-core Yb-doped fiber laser
Year of publicationPublished in:Fiber Lasers XXII: Technology and Systems
M. Bahri, A. Klenke, C. Jauregui, J. Nold, N. Haarlammert, T. Schreiber, J. Limpert
Femtosecond CPA laser system emitting 261W average power, 1.75mJ pulse energy based on coherent combination of a 49-core fiber
Year of publicationPublished in:Fiber Lasers XXII: Technology and Systems
A. Klenke, M. Bahri, C. Jauregui, J. Nold, N. Haarlammert, T. Schreiber, J. Limpert
Average-power scaling of in-band pumped, Tm-doped, fiber laser systems for high peak power pulsed operation
Year of publicationPublished in:Optics Express
M. Lenski, Q. Xu, P. Gierschke, Z. Wang, T. Heuermann, C. Jáuregui, J. Limpert
This contribution explores the average-power scaling potential of in-band pumped, Thulium (Tm-) doped fiber amplifiers for high peak-power operation. These results have been obtained by pumping a Tm-doped, photonic crystal fiber at a wavelength around 1700nm. In one of the experiments reported in this work an average output power of 242 W with a slope efficiency of 80% was obtained. Additionally, we also demonstrate operation up to an average output power of 80 W with no need for active cooling, which further highlights the benefits of this low-quantum defect pump approach. Furthermore, our simulation reveals the average power scaling potential of these systems to the multi-kilowatt level.
Mitigation of Transverse Mode Instability by Incoherent Combination in Multicore Fibers
Year of publicationStatusReview pendingPublished in:Proceedings of SPIE - The International Society for Optical Engineering
Y. Khalil, C. Jauregui, J. Limpert, C. Jáuregui-Misas
Multiplexing information limits in multi-beam ptychography
Year of publicationStatusReview pendingPublished in:Optics Express
D. Penagos Molina, W. Eschen, C. Liu, J. Limpert, J. Rothhardt
Ptychography is a lensless imaging technique where the sample is laterally scanned by the illuminating beam. In multi-beam ptychography multiple beams simultaneously illuminate the sample, enabling faster scanning of larger areas. In this work, we explore the potential of multi-beam ptychography with a large number of illumination channels to enhance imaging throughput. Our findings show that while spatial resolution is reduced compared to single-beam ptychography, multi-beam ptychography still significantly increases throughput. Using synthetic and experimental data, we demonstrate an almost fivefold improvement in throughput, accompanied by reduced memory footprint and overhead time. Furthermore, we present the successful implementation of massively multiplexed multi-beam ptychography with up to 64 channels. These results pave the way for efficient use of light sources with partial spatial or temporal coherence for ptychography, opening new possibilities for high-throughput imaging applications.