Thorlabs' Ytterbia FSL1030X1 Femtosecond Fiber Laser is a high peak power, NIR laser that emits clean, ultrafast pulses centered at 1035 nm. With <220 fs typical pulse width, 3 µJ pulse energy, and a user-tunable repetition rate from 1 to 11 MHz, this fiber laser enables a wide range of applications, including multiphoton microscopy, optogenetics, and precision machining. Its high-energy pulses have typical temporal Strehl ratios of >0.90, corresponding to low temporal pedestals free from any picosecond background, thereby maximizing the usable output power per pulse. This is ideal for applications where reduced excitation powers are desirable to prevent heat-induced sample degradation and photobleaching.
A unique feature of the Ytterbia FSL1030X1 laser is the nearly constant pulse energy as a function of repetition rate. From 1 - 5 MHz, the pulse energy is 3 µJ, so the average power increases linearly depending on the user selected repetition rate. Above 5 MHz, the laser power trends towards its maximum of approximately 20 W, with the pulse energy decreasing to a minimum of 2 µJ at the maximum repetition rate of 11 MHz.
If your application requires higher pulse energies or shorter pulse widths, please contact
The Ytterbia fiber laser is designed for hands-free operation and long-term reliability. Parameters such as repetition rate, output power, and pulse duration can be controlled through a user-friendly GUI. When applying the computer-controlled pulse duration, pulse-width pre-compensation is accomplished without the use of external prisms or gratings. See the Software tab for details on the downloadable GUI.
Three CL5A mounting clamps are included with the laser head as well as two removable handles for easier set up. The FSL1030X1 laser has a beam height of 4.75", marked on the side of the laser. Each laser also ships with a chiller and electronics unit, both of which are rack mountable.
Repetition Rate Tuning Details
The operation of the fiber laser is based upon an oscillator, pulse picker, and a chirped pulse amplifier, yielding reliable turn-key operation and exceptional long-term reliability. The pulse-picking system is based on frequency division of the femtosecond oscillator, which operates at 56 ± 2 MHz. The available repetition rates are given by this oscillator frequency divided by an integer from 5 to the value of the oscillator frequency. For example, when the oscillator frequency is 56 MHz, a divisor of 56 produces an amplified pulse train at 1 MHz, where 1 pulse out of every 56 is passed through the pulse picker and on to the amplifier. As the divisor becomes smaller, the spacing between accessible repetition rates becomes coarser. For example, for divisors 56 and 55, the resulting repetition rates are 1.00 and 1.02 MHz, respectively, while for for divisors of 6 and 5, the repetition rates are 9.33 and 11.20 MHz, respectively. The maximum repetition rate for this example oscillator frequency is 11.2 MHz. The available repetition rates for which the laser is qualified are chosen from a drop-down menu in the software GUI.
Ytterbia Platform
The Ytterbia ultrafast laser platform utilizes a vertical stacking architecture, allowing additional modules, such as the Ytterbia Optical Parametric Amplifier (OPA), to be integrated into the same compact housing as the FSL1030X1 laser. In contrast to traditional wavelength conversion methods that require secondary enclosures and free space alignment, the Ytterbia platform offers enhanced alignment stability and opportunities for system reconfiguration.
Features
- User-Tunable Repetition Rate from 1 - 11 MHz
- Ultrafast <220 fs Typical Pulse Width with Low Pulse Pedestal
- >20 W Output Power at Max Rep Rate
- 3 µJ Pulse Energy from 1 - 5 MHz
- 1035 nm Center Wavelength
- Control via Downloadable Software for Hands-Free Operation (see Software Tab)
- Computer-Controlled Pulse Width Precompensation
- Compact Footprint: 569 mm x 320 mm x 238 mm (22.4" x 12.6" x 9.4")
Applications
- Multiphoton Microscopy
- Photostimulated Optogenetics
- Precision Micromachining of Tissues, Glass, and Plastics
- Optical Parametric Amplifier (OPA) Pumping
- White Light Supercontinuum Generation
- Biological or Ophthalmic Tissue Machining
- Non-Collinear Optical Parametric Amplifier (NOPA) Pumping
- Chemical Spectroscopy
- Terahertz Generation
| Item | FSL1030X1 |
|---|---|
| Optical Specifications | |
| Center Wavelength | 1035 ± 5 nm |
| User Tunable Repetition Ratea | 1 - 11 MHz |
| Pulse Duration (FWHM)b | <220 fs (Typical) <250 fs (Max) |
| Temporal Strehl Ratioc | >0.90 (Typical) >0.85 (Min) |
| Pulse Energy from 1 - 5 MHz | 3 µJ |
| Average Power at Max Rep Rate | >20 W (Min) |
| Mode Field Diameter (1/e2) | 2.0 - 2.5 mm (Typical) |
| Mode Ellipticity | >0.8 (Typical) |
| Beam Quality (M2) | <1.15 (Typical) <1.2 (Max) |
| Polarization | Linear, Vertical |
| Polarization Extinction Ratio | >200:1 |
| Power Stabilityd | <1% RMS over 12 Hours |
| Pointing Stabilityd | <10 μRad/°C (Typical) |
| Dispersion Compensation | -1 x 105 fs2 to 1 x 105 fs2 |
| Optical Head Dimensions (L x W x H) | 569 mm x 320 mm x 238 mm (22.4" x 12.6" x 9.4") |
| Beam Height | 4.75" |
| Electrical Requirements | |
| Input Voltage | 100 - 240 V |
| Frequency | 50 - 60 Hz |
| Power Consumption | Controller: 400 W (Max) Chiller: 600 W (Max) |
| Environmental Requirements | |
| Room Temperature Range | 17 °C - 25 °C |
| Room Temperature Stability | <3 °C over 24 Hours |
Custom Capability: Nonlinear Pulse Compression
The demand for ultrafast lasers has increasingly trended towards more power at shorter pulse durations while retaining ease of use, driven in part by the maturation of the many applications utilizing these ultrafast sources. Some example applications that stand to benefit from a reduction in pulse duration are biological material modification, micro-machining, time-resolved spectroscopy, and THz-generation. The system described here is a custom add-on for the FSL1030X1 fiber laser, providing pulses as short as 39 fs. This work was presented at the Conference on Lasers and Electro-Optics (CLEO) 2022.1
Ultrafast Ytterbium (Yb) fiber lasers in the near infrared combine high pulse energies and high repetition rates but generally have pulse durations in the few hundreds of femtoseconds due to limitations in gain-bandwidth and gain-narrowing. To overcome this limitation, spectral broadening techniques via self-phase modulation in a variety of optical systems and materials have been developed to shorten the pulse duration: single mode fiber at tens of nJ,2 specialty large-mode-area photonic crystal fiber at a few hundreds of nJ to a few µJ,3 gas-filled hollow core fiber at µJ to a few mJ,4 passage through multiple thin optical windows at µJ to a few mJ,5 and finally multi-pass cells with thin plates or high-pressure gas at mJ or higher energies.6
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The output collimated spatial mode of the multimode fiber shows the preservation of the launched LP0,1 mode while broadening the spectrum by a factor of 5.
Fiber-based systems are favorable in that the fundamental waveguide mode ensures a pristine output beam quality and high pointing stability. One of the main challenges to spectral broadening in any type of fiber is the potential for damage to the input fiber face, where at µJ-energy levels, self-focusing plays a critical role in limiting scalability. Spectral broadening solutions for pulse energies greater than 10’s of nJ require exotic or unattainable optical fibers, have catastrophic sensitivity to laser pointing, and introduce high system complexity and cost. To combat these difficulties, while retaining the advantages of a simple single mode fiber for nonlinear spectral broadening, we have pioneered an approach using the fundamental LP0,1 spatial mode of generic multimode fiber.
One example of the capabilities of this approach is presented here. A Thorlabs Ytterbia FSL1030X1 Yb fiber laser was coupled into a multimode fiber, <100 mm in length, with a calculated LP0,1 mode field diameter of ~65 µm. The 1035 nm, 9.5 MHz repetition rate, 200 fs input pulse was broadened to a spectral bandwidth supporting a 36 fs full-width-at-half-maximum (FWHM) transform-limited pulse duration at a pulse energy of 490 nJ (4.7 W of average power).
A Thorlabs' M² Measurement System confirmed a pristine spatial mode profile, with an M2 value of 1.05 and an ellipticity of 96%, as expected from waveguide-based spectral broadening (see the image of the spatial mode in the figure to the right). The output pulse from the prism compressor had a 39 fs FWHM and 10 MW of peak power, which is ~90% of the peak power fundamental limit. This pulse was characterized via second-harmonic generation frequency resolved optical gating (SHG-FROG).
The graphs below show the performance of the input pulse (top) and and output pulse (bottom). For each set of graphs, the SHG-FROG measurement is presented on the left, with the reconstructed spectrum, phase presented in the middle. The transform-limited and reconstructed intensities are presented to the far right, with the peak power and pulse width labeled.
Critically, we have also confirmed that this method of spectral broadening is below the damage threshold of the employed fiber, having logged >1000 hours of runtime.