READ ME File For 'Dataset supporting the University of Southampton Doctoral Thesis "High-energy Picosecond-pulsed Mid-infrared Optical Parametric Oscillators"'

Dataset DOI: 10.5258/SOTON/D3047

ReadMe Author: Yudi Wu, University of Southampton ORCID ID https://orcid.org/0000-0003-1704-3501

This dataset supports the thesis entitled 'High-energy Picosecond-pulsed Mid-infrared Optical Parametric Oscillators'
AWARDED BY: Univeristy of Southampton
DATE OF AWARD: 2024

DESCRIPTION OF THE DATA
This dataset contains: originally measured data for plotting figures within the thesis

This dataset contains:

Figure 3.3 Graphs showing the a) optical pulse and b) output spectrum of the GSLD
Figure 3.5 Graphs showing MOPA's (a) optical spectrum, (b) temporal pulse shape and (c) pulse trace under burst mode operation (note the different vertical scales in (c)).
Figure 3.6 Graph showing the MOPA's full optical spectrum with ASE.
Figure 3.8 Graph showing the OPO’s average idler power (black) with linear fit (red) and conversion efficiency (blue dots) against pump power. The blue line is a guide for the eye.
Figure 3.9 Graphs showing (a) the tunability of the idler from the OPO and (b) a typical idler optical spectrum.
Figure 3.11 Beam quality measurements at (a) low pump power and (b) at maximum pump power.
Figure 3.12 Measurements of the OPO’s idler average power and idler peak power. The vertical-coloured line marks the corresponding window time.
Figure 3.13 Graphs showing a) pump peak power at maximum 14 W for different number of pulses per burst (vertical-coloured lines mark the window times) and b) Idler peak power vs. corresponding pump peak power. The black lines are guides for the eye.
Figure 3.14 Burst pulse traces of the residual pump (a) 500 ns and (b) 25 ns burst window times. The grey area highlights the cavity build-up time.

Figure 4.1 Graphs showing a) temporal pulse shape and b) optical spectrum of the GSLD
Figure 4.3 Spectrum of the core-pumped Yb-fibre amplification stage of the MOPA with ASE.
Figure 4.4 Graphs showing the main spectral peak  of the MOPA at 1-MHz for 0.96 W before the fibres were shortened.
Figure 4.5 Graphs showing a) the signal peak spectrum before and after shortening the Yb gain fibre to 2.5 m and b) the full spectrum of the third Yb amplification stage with ASE
Figure 4.6 Graphs showing a) the full Spectrum and b) the main signal spectrum of the MOPA at 1-MHz for different output powers after the fibres were shortened.
Figure 4.7 Graphs showing a) the full Spectrum and b) the main signal spectrum of the MOPA at 16-MHz for maximum output power of 15.4 W.
Figure 4.10 Graph showing the fibre-feedback OPO’s average idler power (black) with linear fit (red) and conversion efficiency (blue dots) versus pump power for 16-MHz operation. The blue line is a guide for the eye.
Figure 4.11 Graph showing the OPO’s idler spectrum at different pump power for 16-MHz operation. Spectral broadening can be observed with increasing pump power.
Figure 4.12 Graph showing the OPO’s signal spectrum at different powers for 16-MHz operation a) before feedback-fibre, b) after feedback-fibre and c) a comparison of before and after the feedback-fibre at maximum pump power. Spectral broadening can be observed with increasing pump power, with the signal spectrum after the feedback-fibre broader than before the feedback-fibre.
Figure 4.13 Graph showing the temporal pulse shape of the signal within the OPO cavity. At 16 MHz repetition rate, the signal pulse duration is unaffected by nonlinear effects in the feedback-fibre.
Figure 4.16 Graph showing the fibre-feedback OPO’s average idler power (black) with linear fit (red) and conversion efficiency (blue dots) against pump power under 1-MHz operation. The blue line is a guide for the eye.
Figure 4.17 Graph showing the OPO’s idler spectrum at different power under 1-MHz operation. Spectral broadening greater than that at 16-MHz operation can be observed with increasing pump power.
Figure 4.18 Graph showing the OPO’s signal spectrum at different power under 1-MHz operation a) before feedback-fibre, b) after feedback-fibre and c) a comparison of before and after feedback-fibre at maximum pump power. Other than the increase of spectral width with pump power, SC generation can also be observed.
Figure 4.20 Graphs showing the temporal pulse shape of the signal before the feedback-fibre at: a) 2.32 W pump, b) 3.46 W pump and above, and signal after the feedback-fibre at: c) 2.32 W pump, d) 3.46 W pump and above.
Figure 4.21 Graph showing the fibre-feedback OPO’s average a) idler, b) signal and c) total converted power (black) with a linear fit (red) and its respective conversion efficiency (blue dots) against pump power under 1-MHz operation with the OC. The blue line is a guide for the eye.
Figure 4.22 Graph showing the OPO’s idler spectrum at different power under 1-MHz operation with OC. Spectrum broadening is reduced compared to 1-MHz operation without OC.
Figure 4.23 Graph showing the OPO’s signal spectrum at different power under 1-MHz operation with an OC a) before feedback-fibre and b) after feedback-fibre. SC generation is no longer observed.
Figure 4.24 Graphs showing the temporal pulse of the signal a) before the feedback-fibre and b) after the feedback-fibre at different pump powers. Even with an OC of 90 % signal transmission, pulse broadening due to dispersion is still present.
Figure 4.25 Beam quality measurements of signal at (a) low power and (b) at maximum power, and of idler at (c) low power and (d) at maximum power.

Figure 5.2 Graph showing the HCF fibre-feedback OPO’s average idler power with respect to pump pump.
Figure 5.3 Graphs showing the signal spectra a) before and b) after the HCF feedback fibre.
Figure 5.4 Graphs showing the idler spectra of the HCF fibre-feedback OPO at different pump powers.
Figure 5.5 Graphs showing the signal pulse of the HCF fibre-feedback OPO a) before the feedback fibre and b) after the feedback fibre.
Figure 5.6 Signal pulse after the feedback fibre with the higher order mode supressed.
Figure 5.7 Graph showing the HCF fibre-feedback OPO’s average a) idler, b) signal and c) total converted power (black) with linear fit (red) and its respective conversion efficiency (blue dots) against pump power with OC. The blue line is a guide for the eye.
Figure 5.8 Graph showing the spectra of the signal at low and maximum power for the HCF fibre-feedback OPO with 90 % OC. The inset shows the magnified spectra.
Figure 5.9 Graph showing the spectra of the idler at low and max. power for the HCF fibre-feedback OPO with 90 % OC. The inset shows the magnified spectra.
Figure 5.10 Tunability of the (a) signal and (b) idler from the fibre-feedback OPO and the corresponding maximum power.Figure 5.12 Graph showing signal pulse from the HCF fibre-feedback OPO with 90 % OC. Due to the narrow linewidth of the signal spectrum, the pulse width was maintained at 120 ps.
Figure 5.13 Graph showing the 1-MHz pulse train of the idler.
Figure 5.14 Beam quality measurements of signal at (a) low power and (b) at maximum power, and of idler at (c) low power and (d) at maximum power.
Figure 5.17 Beam quality measurement of the MOPA output at maximum power.
Figure 5.18 Beam quality measurements of signal at (a) low power and (b) at maximum power, and of idler at (c) low power and (d) at maximum power of the HCF fibre-feedback OPO with the redesigned cavity with larger signal beam waist.
Figure 5.20 The beam quality of signal and idler at maximum power from the HCF fibre-feedback OPO using aspheric lens of focal length 18.4-mm ((a) and (b) respectively), 15.28-mm ((c) and (d) respectively) and 13.86-mm ((e) and (f) respectively).

Figure 6.1 Graphs showing the GSLD's output a) optical pulse and b) optical spectrum.
Figure 6.3 Beam quality measurement of the output of the taper. Inset shows the far field beam profile.
Figure 6.5 Spectrum of the third stage amplifier with 1.25-m Yb gain fibre at 300-mW output power.
Figure 6.6 Beam quality of MOPA output at a) 1.4 W and b) 16 W with 75-mm Yb-fibre coil diameter. The insets show the far field beam profiles.
Figure 6.8 Beam quality measure of the MOPA output at 37-W maximum power with 50-mm fibre coil diameter. The inset shows the far field beam profile.
Figure 6.9 Graphs showing a) the MOPA output power against pump power and b) the power stability over a 1-hour time frame at maximum output power.
Figure 6.10 Output optical pulse of the MOPA. The inset illustrates the 1.0-MHz pulse train.
Figure 6.11 Graphs showing a) the full Spectrum and b) the main signal spectrum of the MOPA.
Figure 6.13 Graphs showing the OPO’s Average idler power with linear fit (black), average signal power with linear fit (red), total converted power with linear fit (green) and conversion efficiency (blue dots) against pump power for. The blue line is a guide for the eyes.
Figure 6.15 Graphs showing the OPO’s Average idler power with linear fit (black), average signal power with linear fit (red), total converted power with linear fit (green) and conversion efficiency (blue dots) against pump power for. The blue line is a guide for the eyes.
Figure 6.17 Graphs showing the OPO’s Average idler power with linear fit (black), average signal power with linear fit (red), total converted power with linear fit (green) and conversion efficiency (blue dots) against pump power for. The blue line is a guide for the eyes.
Figure 6.18 Graph showing the spectrum of the second stage amplifier with and without the 1040-nm BPF.
Figure 6.20 Graph showing output power against pump power of the MOPA with 1040-nm BPF.
Figure 6.21 Graph showing the OPO’s average idler power with linear fit (black), average signal power with linear fit (red), total converted power with linear fit (green) and conversion efficiency (blue dots) against pump power (the blue line is a guide for the eye).
Figure 6.22 Graph showing the power stability of the OPO’s signal (red) and idler (black), and the MOPA pump at maximum output over a 1-hour time frame.
Figure 6.23 Graphs showing: a) the spectra of signal (red) and idler (black) from the OPO, and the pump spectrum (blue) for comparison. The inset shows the magnified signal spectrum; and b) the OPO’s output signal pulse.
Figure 6.24 Graphs showing: a) tunability of the signal and idler, and (b) the corresponding maximum output powers and calculated pump acceptance bandwidths. The orange dashed horizontal line marks the 1.3-nm spectral width of the pump (with the right vertical axis).
Figure 6.25 Beam quality measurements of signal at (a) low power and (b) at maximum power, and idler at (c) low power and (d) maximum power.

Figure 7.4 Graph showing Delivered against input average powers through 5-m long and 108-m-long “FIBRE 1” at a wavelength of 3.0 μm.
Figure 7.5 Graph showing the tunable delivered MIR laser spectrum through 100-m long “FIBRE 1”.
Figure 7.6 Graph showing the beam quality measurements for the 100 m long “FIBRE 1” at maximum output power. Inset: the beam profile at the output of the 100 m long “FIBRE 1”.
Figure 7.7 Power stability measurements for 5 m long and 100 m long “FIBRE 1” over a 1-hour time period at maximum delivered power.
Figure 7.8 Graph showing Delivered versus input average powers through 5-m long and 108-m-long “FIBRE 2” at a wavelength of 3.3 μm.
Figure 7.9 Graph showing the tunable delivered MIR laser spectrum through 108-m length of “FIBRE 2”.
Figure 7.10 Graph showing the beam quality measurements for the 108 m length of “FIBRE 2” at maximum output power. Inset: the beam profile at the output of the 108 m length of “FIBRE 2”.
Figure 7.11 Power stability measurements for 5 m and 108 m “FIBRE 2” over a 1-hour time period at maximum delivered power.


Date of data collection: 2020-2023

Information about geographic location of data collection: ORC, University of Southampton

Licence:
CC-BY

Related projects/Funders:
EP/R513325/1, EP/N509747/1, EP/P027644/1, EP/P030181/1, EP/T020997/1, EP/V038036/1, European Research Council
(682724), 

Related publication:
Journal:
Y. Wu, Q. Fu, S. Liang, F. Poletti, D. J. Richardson, and L. Xu, "15-μJ picosecond hollow-core-fiber-feedback optical parametric oscillator," Opt. Express 31(14), 23419-23429 (2023).
Q. Fu, Y. Wu, I. A. Davidson, L. Xu, G. T. Jasion, S. Liang, S. Rikimi, F. Poletti, N. V. Wheeler, and D. J. Richardson, "Hundred-meter-scale, kilowatt peak-power, near-diffraction-limited, mid-infrared pulse delivery via the low-loss hollow-core fiber," Opt. Lett. 47(20):5301-5304, Oct 2022
Y. Wu, S. Liang, Q. Fu, T. D. Bradley, F. Poletti, D. J. Richardson, and L. Xu, "High-energy, mid-IR, picosecond fiber-feedback optical parametric oscillator," Opt. Lett. 47(14):3600-3603, July 2022
Y. Wu, S. Liang, Q. Fu, L. Xu, and D. J. Richardson, “Compact picosecond mid-IR PPLN OPO with controllable peak powers,” OSA Continuum, 3(10):2741-2748, Oct 2020.

Conference:
Y. Wu, Q. Fu, S. Liang, F. Poletti, D. J. Richardson, and L. Xu, "High-energy picosecond optical parametric oscillator with using hollow-core fiber" in SPIE Photonics West 2024, 2024
Y. Wu, S. Liang, Q. Fu, F. Poletti, D. J. Richardson, and L. Xu, "11-μJ picosecond-pulsed hollow-core-fiber-feedback optical parametric oscillator," in CLEO/Europe-EQEC 2023, Munich, Germany, pp. 01-01, 2023
Q. Fu, Y. Wu, I. A. Davidson, N. V. Wheeler, L. Xu, F. Poletti, and D. J. Richardson, “High-beam-quality, Mid-infrared Pulse Delivery over a 118m Length of Low-loss Hollow-Core Fiber,” in Optica Advanced Photonics Congress 2022, paper SoM3I.1., Technical Digest Series (Optica Publishing Group), 2022
Y. Wu, S. Liang, Q. Fu, T. Bradley, L. Xu, F. Poletti, D. J. Richardson, “High-energy, mid-IR, short-pulsed, hollow-core-fiber-feedback OPO,” in Proc. SPIE PC11985, Nonlinear Frequency Generation and Conversion: Materials and Devices XXI, 2022
Y. Wu, S. Liang, Q. Fu, L. Xu, and D. J. Richardson, “High-energy, mid-IR, picosecond fiber-feedback OPO,” in Laser Congress 2021 (ASSL, LAC), paper ATu2A.6, Optica Publishing Group, 2021.
Y. Wu, S. Liang, Q. Fu, L. Xu, and D. J. Richardson, “Compact picosecond mid-IR PPLN OPO in burst-mode operation,” in Europhoton 2020, paper Th-A3.5. The European Physical Society - Quantum Electronics and Optics Division, 2020.


Date that the file was created: April, 2024