


TOPO
Widely Tunable High-Power Continuous-Wave OPO Laser System for Mid-infrared Spectroscopy and Applications
- 1.45 - 4.0 µm (2500 - 6900 cm-1)
- Narrow linewidth: 2 MHz (1·10-4 cm-1)
- Hands-free motorized tuning
- 300 GHz (10 cm-1) mode-hop-free tuning range
- Easy all-digital DLC pro control
Mid-infrared tunable lasers between 2 – 5 µm are necessary tools for applications like high resolution molecular spectroscopy and gas sensing, mid-infrared integrated photonics, optical component characterization, and quantum optics. For this reason, TOPTICA has developed a continuous wave optical parametric oscillator that delivers the widest coverage of any MIR laser in this wavelength range. This system, the TOPO, has high power and narrow linewidth, and is capable of fast phase and frequency modulation necessary for sensitive gas phase MIR spectroscopy techniques.
The TOPO fills a critical gap in existing continuous wave laser technology. TOPTICA offers various tunable diode laser platforms to provide wide wavelength coverage below 2 µm. Wavelengths longer than 4 µm can be generated by quantum cascade lasers. Interband cascade lasers are the only laser diode technology with direct emission between 2 – 4 µm, and these lasers tend to have very small tuning ranges (few nm) and low output power (1 mW). The TOPO relies on TOPTICA’s long experience with efficient nonlinear frequency conversion of diode lasers to generate a high power MIR laser with wide tuning range.
The 2 – 5 µm range (5000 – 2000 cm-1) is of interest for MIR spectroscopy because molecular stretch vibrations tend to have absorption features here. The TOPO is an ideal tool for direct tunable laser absorption spectroscopy of such molecular features. Direct TDLAS has limited sensitivity, detecting absorption coefficients α down to approximately 10-4 per cm. More sensitive techniques require manipulation of the laser source. Fast frequency modulation is required for frequency modulation spectroscopy (minimum detectable α ~ 10-6 cm-1) and laser frequency stabilization is required for cavity-enhanced spectroscopy (minimum detectable α ~ 10-8 cm-1) and cavity ring-down spectroscopy (minimum detectable α < 10-10 cm-1). TOPTICA’s laser modulation and stabilization electronics, developed for quantum technology applications, transfer seamlessly to the TOPO for these sensitive absorption spectroscopy techniques.
Of course, the TOPO is useful not only for MIR spectroscopy, but also in any case where a mid-IR laser is required. On-chip MIR photonic devices are used for gas and biological sensing, and the TOPO is a useful tool for MIR integrated photonic characterization. Quantum memories generate single photons at wavelengths corresponding to transitions in atoms, quantum dots, and vacancy centers, and these wavelengths are often unsuitable for long distance propagation in optical fibers. Nonlinear frequency conversion of single photons to telecom wavelengths requires high power in a narrow spectrum at a strange wavelength, and the TOPO excels at providing exactly this kind of light. And undoubtedly there are other applications for the TOPO waiting to be found, please submit a request for more information and TOPTICA will be glad to work with you!
Characteristic Tuning Curve
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Specification
DLC TOPO Signal Idler Coarse tuning range (standard system) 1.45 - 2.07 µm
4830 - 6900 cm-12.19 - 4.00 µm
2500 - 4570 cm-1Coarse tuning range (high power system) 1.43 - 2.07 µm
4830 - 7000 cm-12.19 - 4.20 µm
2380 - 4570 cm-1Mode hop free tuning range -- > 30 GHz (> 100 GHz typ.) Linewidth < 100 kHz
< 1x10-5 cm-1< 2 MHz (< 100 kHz opt.)
< 1x10-4 cm-1Output power (standard system) > 10 mW at > 1.45 µm
> 2 W at > 1.55 µm
> 3 W peak> 10 mW at < 4.00 µm
> 1 W at < 3.6 µm
> 2 W peakOutput power (high power system) > 10 mW at > 1.43 µm
> 4 W at > 1.60 µm
> 5 W peak> 10 mW at < 4.20 µm
> 2 W at < 3.5 µm
> 5 W peakFrequency modulation and lock PZT modulation PZT modulation, pump frequency modulation Beam Quality Factor M2 < 1.2 at < 3.6 µm < 1.2 at < 3.6 µm Control interfaces DLC pro touchscreen, PC software, Ethernet, USB, analog remote control Warm-up time 30 min. typ. Dimensions seed laser head (H x W x D) 55 x 130 x 165 mm Dimensions OPO head (H x W x D) 150 x 240 x 465 mm Dimensions fiber amplifier (H x W x D) 133 x 482 x 438 mm Dimensions control unit (H x W x D) 154 x 450 x 348 mm Power consumption Typ. < 250 W PC Interface Ethernet, USB, analog control Environment temperature 15 - 30 °C (operating), 0 - 40 °C (storage and transport) Environment humidity non-condensing - Additional Information
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Options
Narrow linewidth
The optical spectrum of the idler output is a convolution of the seed laser and signal spectra. The standard TOPO uses the DLC DFB pro as its seed, with 2 MHz linewidth. An alternate seed option is the DLC CTL 1050, which has < 10 kHz linewidth. This results in an idler linewidth of < 100 kHz. Fiber Coupling
(FiberDock)
TOPTICA’s patented fiber coupler provides highest single-mode fiber-coupling efficiencies, easy alignment and at the same time highest stability. With this option, fiber coupling is added TOPO signal and idler probe outputs for convenient power and wavelength monitoring. TOPTICA additionally offers a wide range of single-mode and polarization-maintaining fibers, including fiber-optic beam splitters. Laser Locking Electronics A broad variety of electronic locking modules is available for frequency stabilization. -
Applications
- Molecular Spectroscopy
- Quantum Optics
- Materials Testing
- Biophotonics
- Physical Chemistry
- Downloads
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Literature
- Article: High-resolution, broadly-tunable mid-IR spectroscopy using a continuous wave optical parametric oscillator, Optical Express (2021)
- Whitepaper:Enabling high-resolution spectroscopy over the molecular stretch region, 2020
- Poster: David Foote Broadly-tunable, High-resolution Mid-IR Spectroscopy, CLEO 2020
- Article: Ulrich Eismann Direct and frequency-converted diode lasers provide all wavelengths for holography, Laser Focus World (2018), German version, Chinese version, Japanese version, French version
- Article: R. Kirner et al., Mask-aligner lithography using a continuous-wave diode laser frequency-quadrupled to 193 nm, Optics Express (2018)
- Article: Active and passive stabilization of a high-power UV frequency-doubled diode laser, CLEO, OSA Technical Digest (Optical Society of America, 2016)
- Article: Short, shorter, shortest: Diode lasers in the deep ultraviolet, Laser Focus World, June 2016
- Article: Kurz, kürzer, am kürzesten, Best of (2015)
- Article: More colors! Diode lasers reach Yellow and Orange, Physics' Best (2013)
- Article: Frequenzkonvertierte cw-Lasersysteme für Forschung und Industrie, Physik Journal (2007)
- Application Note : Phase and Frequency Locking of Diode Lasers
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Related Products
- Tunable diode laser: CTL
- Frequency converted lasers: SHG pro, DL-SHG pro, TA-SHG pro, TA-FHG pro