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Astrella Ultrafast Ti : Sapphire Amplifier The Astrella laser from Coherent is an ultrafast femto-second laser system that comes with an integrated Vitara Ti:sapphire oscillator laser pulse of repetition rate 80 MHz, which is amplified using a nonlinear crystal providing the amplified output pulse energy of nearly 6 mJ and the pulse reputation rate of 1 kHz. The pulse width of the amplified laser out is nearly 35 fs that allows us to perform the ultrafast pump-probe laser spectroscopy of the exciting materials and superconductors. Reference |
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Photoconductive Antenna based THz-TDS system GaAs based Photoconductive antenna switches are one of the most used Terahertz generation sources. It is driven by a low power femto-second pulses which generates the charge carriers within the crystal. Application of voltage bias on emitter accelerates the charge carriers to generate THz radiation and this radiation is further detected when its field is used to drive the charge carriers on the detector end. |
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ZnTe crystal based THz-TDS system We have ZnTe crystal-based terahertz time domain spectroscopy setup. In the setup an amplified femto-second optical pulse of wavelength 800 nm is shined on <110> cut ZnTe crystal and under the proper phase matching conditions, the THz pulse is generated through optical rectification processes. To detect the generated THz, electro-optic sampling method has been used where the low power optical pulse passing through another ZnTe detector crystal experiences the polarization rotation due to the incident THz electric field. Reference |
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Optical Pump-Terahertz Probe system We employ ZnTe crystal-based THz system for the time resolved optical pump and terahertz probe (OPTP) measurements. We have 400 and 800 nm optical pump beam to photoexcite the samples where we can scan the dynamics at nanoseconds time scales. |
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Picometrix T-Ray 5000 T-Ray 5000 Picometrix setup allows state of the art terahertz research to be performed in the real-time platform. The modular construction facilitates the laser propagation through the fibre which eliminates the optical bench significantly. This striking advantage allows an easy modulation in the system to perform characterizations in transmission as well as reflection geometry. |
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Advanced Research 4K Cryostat We use a closed cycle (ARS) optical cryostat to cool down the superconducting samples. In this system, low temperature is achieved by cooling the helium vapors which is in contact with sample space. In this process, the refrigerator of the cryostat is kept in a vacuum to eliminate convection heat transfer to the cold internal parts to maintain low temperatures. A radiation shield is used to minimize the radiant heat load on the cold stage and is cooled by helium exhausting from the heat exchanger. A temperature controller and thermocouple are used to control and monitor the temperature of the sample holder, respectively. |
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TeraScan 1550 The TeraScan 1550 combine mature DFB diode lasers with state-of-the-art GaAs or InGaAs photomixers. The system sets new benchmarks in terms of terahertz power, spectral selectivity, high resolution and dynamic range. Continuous-wave (CW) terahertz radiation is obtained by so-called optical heterodyning in high-bandwidth semiconductors: The output of two CW lasers is converted into terahertz radiation, exactly at the difference frequency of the lasers. Thermal tuning of the grating pitch yields very wide continuous frequency scans (typ. > 1000 GHz / diode). |
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Virginia Diodes Inc The Virginia Diodes Inc (VDI) frequency extension modules expand the operating range of microwave signals generators up into the millimetre frequency range (260GHz to 400 GHz). They combine high output power and low phase noise with broad frequency coverage over full waveguide bands. Standard features include TTL-controlled on/off modulation up to approximately 1 kHz and voltage-controlled RF attenuation (UCA). The VDI setup paired with the signal generator and analyzer enables experimental measurements of conventional and photonic topological insulators (PTI) waveguiding and also free space measurements if the horn antenna attachment is used. |