Laser Quantum THz

THz radiation is a fast growing area of research due to its non-ionising nature and transparency to many materials. Combined with time domain spectroscopy, it can provide information on the samples effect on amplitude and phase of the radiation, thereby provide more information than other spectroscopic techniques.

The HASSP-THz is a fully configured pump-probe Asynchronous Optical Sampling instrument that instead of using mechanical translation stages to form the time delay between pump and probe pulses, uses two pulse trains with a slightly offset repetition rate. This greatly improves the resolution of any experiment. 

Laser Quantum Tera-SED produces intense terahertz radiation after excitation with femtosecond laser pulse

Laser Quantum Tera-SED

 

Above: Basic THz generation principle of the Tera-SED emitters. The fs laser radiation (red) comes from the top and excites the GaAs substrate (blue). Every second gap between the + and – electrodes is masked with an isolation layer (green) and gold (yellow) in order to inhibit destructive interference between THz fields emitted from adjacent gaps in the far-field.

The Laser Quantum Tera-SED is a device emitting intense terahertz (THz) radiation after excitation with a femtosecond (fs) laser pulse. It converts the light from the optical regime into the THz regime with a conversion efficiency of up to 2 x 10-3. The impulsive excitation inherently leads to THz pulses covering a broad spectrum in the frequency regime. The spectrum covers almost two decades from about 100GHz up to 7THz with an intensity peak at 1THz (see figure 1). In this frequency range the electric field of the light is directly measurable in amplitude and phase which is important for a large variety of scientific and technological applications.

 

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Next Generation THz from Toptica: Fast, compact and cost effective

TOPTICA presents new cw THz System with 1.5 µm lasers

At the recent Photonics West exhibition, TOPTICA Photonics presented the most compact frequency-domain terahertz spectrometer built to-date. The system combines TOPTICA’s new TeraBeam, a highly integrated twocolor diode laser, with newly developed InGaAs/InP emitter and detector technology (Fraunhofer Heinrich-Hertz Institute, Berlin, Germany).

The new cw THz system features a fast scan option, which reduces the acquisition times in cw THz spectroscopy by more than two orders of magnitude and acquires a complete THz spectrum (e.g. 50-1200 GHz, sub-GHz resolution) in less than a minute. Thus far, research in the field of frequency-domain (cw) terahertz has largely been carried out with GaAs photomixers, requiring laser wavelengths below 870 nm. Whilst excellent results in terms of bandwidth and signal quality have been obtained, the complexity of the optical source and a variety of non-standard optical components resulted in a price level inadequate for widespread industrial use.

Toptica TeraFlash: Time-domain terahertz spectroscopy

Toptica TeraFlash

TOPTICA introduces the new TeraFlash system, a table-top platform for time-domain terahertz spectroscopy. The all-fibre design is based on mature 1.5 µm telecom technology, combining TOPTICA’s established femtosecond fibre lasers and state-of-the-art InGaAs antennas.

Using a highly precise delay stage, the TeraFlash achieves a peak dynamic range of more than 70 dB. Users can choose between a “precisescan” mode and a “fast scan” mode. In “precise scan” mode a bandwidth of 4 THz and a resolution better than 10 GHz are attained. Alternatively, in “fast scan” mode, a pulse trace is acquired in only 50 ms. The fibre-coupled antenna modules can be conveniently arranged, depending on the needs of the experiment. Integrated in the system is TOPTICA’s FemtoFErb 1560, the most compact ultrafast laser on the market. The SAM mode-locked fibre oscillator and the usage of polarization-maintaining fibres ensure a high robustness and alignment-free, “hands-off” operation. The TeraFlash system is a perfect solution for applications such as high-bandwidth spectroscopy (e.g. of explosives or liquid crystals) and industrial process control.

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Toptica: FemtoFErb – the most compact and cost effective laser source for THz generation

FemtoFErb 780 01

TOPTICA’s new FemtoFErb is a turnkey laser system providing 100 mW average power at 1560 nm and a pulse duration of less than 150 fs at 100 MHz repetition rate. Using the same compact platform as TOPTICA’s PicoFYb, the FemtoFErb is a robust all-fiber setup based on Erbium doped fiber and saturable absorber mirror mode-locking (SAM) technology. The compact system includes all necessary control electronics and is equipped with a direct polarization maintaining fiber output interface. The FemtoFErb is an ideal solution for Time-Domain Terahertz generation or for metrology applications allowing highest accuracy laser-based distance measurements.

Also recently released: The new FemtoFiber pro UCP provides a super-continuum between 980 – 1400 nm and more than 30 mW output power. It shows pulse durations even below 25 fs, the fastest one can get on the market from a turnkey SAM modelocked fiber laser system. The system is ideally suited for biophotonics, pump-probe experiments or fs?spectroscopy. The UCP option expands TOPTICA’s successful FemtoFiber proseries and will be live demonstrated at the forthcoming Ultrafast Phenomena conference exhibition.

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