{"title":"THz Instruments","description":"\u003cp\u003eInstrumentation for terahertz beamlines: real-time microbolometer terahertz cameras for beam profiling and imaging, and optical choppers that supply the modulation reference for lock-in detection.\u003c\/p\u003e","products":[{"product_id":"thz-optical-chopper-model-300cd","title":"Optical Chopper, 5 Hz - 3 kHz, 102 mm Blade, Lock-in Reference Source","description":"\u003ch2\u003eOverview\u003c\/h2\u003e\n\u003cp\u003eAn optical chopper is a rotating slotted blade that periodically blocks a laser beam, converting a continuous signal into an amplitude-modulated one at a precisely known frequency. In a terahertz time-domain spectrometer the chopper sits in the pump arm and supplies the reference frequency that the lock-in amplifier demodulates against. This unit covers 5 Hz to 3 kHz as standard with a frequency stability of 0.1%, and can be extended from 15 mHz to 40 kHz with alternative blades.\u003c\/p\u003e\n\u003ch2\u003eWhy chopping is essential in THz-TDS\u003c\/h2\u003e\n\u003cp\u003eThe electro-optic sampling signal is a very small differential photocurrent riding on a large DC background, and it is buried in 1\/f laser noise, mechanical drift and detector noise. Chopping the pump beam moves the terahertz-induced signal to a well-defined carrier frequency, and the lock-in amplifier then rejects everything outside a narrow band around that frequency. Choosing a chopping frequency that is not harmonically related to the mains frequency, and not close to any mechanical resonance of the table, typically buys 40 to 60 dB of dynamic range.\u003c\/p\u003e\n\u003ch2\u003eBlade and mechanical design\u003c\/h2\u003e\n\u003cp\u003eThe 102 mm blade is photochemically etched rather than punched, so the slot edges are clean and the duty cycle is well defined; it is blackened to suppress back-reflection of the blocked pump beam into the beamline, and demagnetised so that it does not couple stray fields into nearby detectors. The open-frame head keeps the aperture accessible and lets the blade be positioned close to a beam waist, which minimises rise time and therefore modulation sidebands.\u003c\/p\u003e\n\u003ch2\u003eIntegration\u003c\/h2\u003e\n\u003cp\u003ePlace the chopper at or near a focus in the pump arm so the beam is fully blocked and fully passed in the shortest possible time. Feed the TTL reference output to the lock-in amplifier external reference input. Note that the chopper head, not the controller, is the element that occupies space on the optical table and must be included in the mechanical layout; the controller is normally rack- or shelf-mounted off the table.\u003c\/p\u003e\n","brand":"WaveQuanta","offers":[{"title":"Default Title","offer_id":48986395050138,"sku":"WQ-THZ-CHOPPER-300CD","price":0.0,"currency_code":"SGD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0734\/6156\/3546\/files\/WQ-THZ-CHOPPER-300CD-card-square_a309e4b8-0f93-4036-a4f2-71781513aebe.jpg?v=1786343962"},{"product_id":"thz-fiber-optical-delay-line-odl","title":"Fiber-Coupled Optical Delay Line ODL, 5 fs Resolution, up to 50 ns Range","description":"\u003ch2\u003eOverview\u003c\/h2\u003e\n\u003cp\u003eAn optical delay line is the component that makes time-domain spectroscopy possible. This is a fibre-coupled, high-speed unit with 5 fs resolution, delay range up to 50 ns, typical insertion loss of 0.8 dB for sub-nanosecond models, return loss above 55 dB and a working band of 1250 to 1650 nm, in a compact package that runs from -10 to +70 C.\u003c\/p\u003e\n\u003ch2\u003eWhy the delay line is the heart of a TDS system\u003c\/h2\u003e\n\u003cp\u003eTerahertz time-domain spectroscopy does not measure the terahertz field directly in real time; it samples it. The probe pulse is scanned in arrival time relative to the terahertz pulse and the detected signal is recorded point by point, so the mechanical delay maps into a time axis through the relation dt = 2dx\/c. Everything downstream depends on that axis: the resolution of the delay stage sets the highest frequency you can resolve, and the total travel sets the frequency resolution after the Fourier transform.\u003c\/p\u003e\n\u003ch2\u003eFibre coupling versus a free-space stage\u003c\/h2\u003e\n\u003cp\u003eA conventional free-space delay stage needs a retroreflector, careful alignment, and a beam path whose length changes as the stage moves, which means the beam pointing and spot size at the detector both drift during a scan. A fibre-coupled delay line removes all of that: the light stays in fibre, alignment does not change with position, and the polarisation dependent loss below 0.1 dB means the polarisation state at the output is stable across the whole travel. For a fibre-based terahertz spectrometer it is the obvious architecture.\u003c\/p\u003e\n\u003ch2\u003eSpecifying a unit\u003c\/h2\u003e\n\u003cp\u003ePick delay range from the frequency resolution you need, since the Fourier transform resolution is set by the total scan window. Sub-nanosecond models are the fastest to deliver and cover most standard time-domain work; longer stages extend the resolution but take longer to build. Fibre type and connector are customisable, so state the source and antenna interfaces at the time of enquiry.\u003c\/p\u003e\n","brand":"Swiss Terahertz","offers":[{"title":"Default Title","offer_id":48987935244442,"sku":"SWT-ODL","price":0.0,"currency_code":"SGD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0734\/6156\/3546\/files\/SWT-ODL-card-square_9588699e-fb3c-4ef4-ab4c-64eb99d56289.jpg?v=1786343790"},{"product_id":"thz-high-voltage-modulator-hvm","title":"High Voltage Modulator HVM for Photoconductive Antennas","description":"\u003ch2\u003eOverview\u003c\/h2\u003e\n\u003cp\u003eThe HVM is a very compact modulated high-voltage source built for driving photoconductive antenna terahertz emitters. It takes a 3.3 to 5 V logic-level square wave between 100 Hz and 1 MHz plus a 12 V DC supply, and delivers a 100 V peak square wave with rising and falling edges under 50 ns, in a 70 x 50 x 20 mm package.\u003c\/p\u003e\n\u003ch2\u003eWhy bias modulation instead of an optical chopper\u003c\/h2\u003e\n\u003cp\u003eA photoconductive antenna only radiates terahertz when it is biased, so switching the bias switches the terahertz output. That gives the same modulation a mechanical chopper would provide for lock-in detection, but with no moving parts, no acoustic noise, no vibration coupled into the table, and modulation frequencies far above what a chopper wheel can reach. Higher modulation frequency moves the measurement further from 1\/f laser and amplifier noise, which directly improves dynamic range.\u003c\/p\u003e\n\u003ch2\u003eWhere the edge speed matters\u003c\/h2\u003e\n\u003cp\u003eSub-50 ns switching edges mean the antenna bias is well defined for essentially the whole of each half cycle even at the top of the frequency range. Slow edges would leave the antenna in an ill-defined partially biased state for a significant fraction of the cycle, which shows up as modulation sidebands and as a reduced effective duty cycle in the lock-in signal.\u003c\/p\u003e\n\u003ch2\u003eIntegration notes\u003c\/h2\u003e\n\u003cp\u003eDrive the trigger input from the same clock that the lock-in amplifier uses as its reference, so the demodulation is exactly phase locked to the emitter. Because the unit is small enough to sit next to the antenna, keep the high-voltage lead short: a long bias cable both slows the effective edge and radiates the switching transient into nearby detection electronics.\u003c\/p\u003e\n","brand":"Swiss Terahertz","offers":[{"title":"Default Title","offer_id":48987935801498,"sku":"SWT-HVM","price":0.0,"currency_code":"SGD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0734\/6156\/3546\/files\/SWT-HVM-card-square_c5c3c576-58fe-45d2-8549-dd509047325f.jpg?v=1786343779"},{"product_id":"thz-pca-scanner-imaging-spectrometer","title":"PCA Scanner THz Imaging Spectrometer, Portable, \u003e 5 THz","description":"\u003ch2\u003eOverview\u003c\/h2\u003e\n\u003cp\u003eThe PCA Scanner is a fibre-coupled photoconductive antenna terahertz time-domain spectrometer built for work outside a stable optical laboratory. It covers beyond 5 THz with better than 75 dB dynamic range as standard, extends to beyond 6 THz and past 100 dB with options, and reaches better than 60 dB in under ten seconds of acquisition.\u003c\/p\u003e\n\u003ch2\u003eReal-time imaging instead of raster scanning\u003c\/h2\u003e\n\u003cp\u003eA conventional terahertz imaging system builds a picture by moving the sample point by point through a focus, which turns a single image into hours of acquisition. Pairing the spectrometer with a microbolometer camera replaces that raster scan with a direct exposure, so an image is captured in about a second. For any application where the sample is large, moves, or simply cannot wait, that is the difference between a feasible measurement and an impractical one.\u003c\/p\u003e\n\u003ch2\u003eBuilt to leave the lab\u003c\/h2\u003e\n\u003cp\u003eThe enclosure is aluminium as standard and titanium as an option, and the instrument is designed to be transported and used in the field rather than bolted to an optical table. That opens applications that laboratory spectrometers cannot reach: drone-borne aerial inspection, in-situ measurement of structures, and survey work in environments where bringing the sample to the instrument is not possible.\u003c\/p\u003e\n\u003ch2\u003eConfiguration options\u003c\/h2\u003e\n\u003cp\u003eThe instrument can be supplied in transmission, in reflection with an optional angular scan, as dual transmission or dual reflection, with two spectroscopy units, or in a real-time imaging configuration. The terahertz relay optics can be off-axis parabolic mirrors for achromatic performance or TPX lenses for compactness. Applications include terahertz spectroscopy, non-destructive testing and quality control, and layer thickness measurement.\u003c\/p\u003e\n","brand":"Swiss Terahertz","offers":[{"title":"Default Title","offer_id":48987936227482,"sku":"SWT-PCA-SCANNER","price":0.0,"currency_code":"SGD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0734\/6156\/3546\/files\/SWT-PCA-SCANNER-card-square_1bb32392-d0fa-4642-a0b5-4c5b51244bfb.jpg?v=1786343769"},{"product_id":"thz-tera-bullet-intense-spectrometer","title":"Tera-Bullet Intense THz Spectrometer","description":"\u003ch2\u003eOverview\u003c\/h2\u003e\n\u003cp\u003eTera-Bullet is a complete intense terahertz spectrometer: an organic-crystal source, a broadband relay designed for diffraction-limited focusing, and an electro-optic sampling detection arm, supplied and aligned as one system. It is aimed squarely at nonlinear terahertz spectroscopy, where what matters is the peak electric field delivered to the sample rather than average power or convenience.\u003c\/p\u003e\n\u003ch2\u003eWhy diffraction-limited focusing is the whole point\u003c\/h2\u003e\n\u003cp\u003ePeak field at the sample scales inversely with the focal spot area, so a system that focuses a broadband terahertz pulse to the diffraction limit reaches field strengths that an ordinary relay cannot, from the same source energy. Achieving that across an octave-spanning bandwidth is difficult, because every frequency component must arrive at the same place at the same time. That broadband focusing behaviour is what distinguishes this system from a spectrometer assembled from individual components.\u003c\/p\u003e\n\u003ch2\u003eOrganic crystal emitters\u003c\/h2\u003e\n\u003cp\u003eThe system is built around organic crystal emitters such as DSTMS, OH1, BNA and DAST, which offer nonlinear coefficients far above inorganic alternatives and give both wide bandwidth and high field. Crystal choice follows the available pump wavelength: BNA works directly at 800 nm or around 1.03 um, while DSTMS, OH1 and DAST are phase matched near 1.3 to 1.5 um and therefore need an optical parametric amplifier.\u003c\/p\u003e\n\u003ch2\u003ePlanning an installation\u003c\/h2\u003e\n\u003cp\u003eThis is a laser-matched system rather than a catalogue item. The pump laser energy, pulse duration and repetition rate determine which emitter is appropriate, what field is achievable, and which detection configuration makes sense, so the specification is settled together with the laser. Contact us with your existing or planned laser parameters and we will work through the configuration with you.\u003c\/p\u003e\n","brand":"Swiss Terahertz","offers":[{"title":"Default Title","offer_id":48987938652314,"sku":"SWT-TERABULLET","price":0.0,"currency_code":"SGD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0734\/6156\/3546\/files\/SWT-TERABULLET-card-square_4ecc5e3d-7353-4a80-9948-095cfa8722f3.jpg?v=1786343758"},{"product_id":"intense-thz-spectroscopy-system-turnkey","title":"Intense THz Spectroscopy System, Turnkey, \u003e 10 MV\/cm Peak Field","description":"\n\u003ch2\u003eOverview\u003c\/h2\u003e\n\u003cp\u003eThe Intense THz Spectroscopy System integrates a femtosecond ytterbium driver, a\nfew-cycle multi-pass-cell compressor and an intense terahertz time-domain spectrometer\ninto a single pre-aligned platform. It is built for groups that need field-driven,\nnonlinear and high-dynamic-range terahertz spectroscopy without assembling and\nstabilising the beamline themselves.\u003c\/p\u003e\n\u003cp\u003eWhat sets the source apart is the shape of its spectrum. Most terahertz sources spike\nat one frequency and fall away either side, so a measurement is strong at the peak and\nnoisy everywhere else. The STFT output instead stays within 10 dB of its peak right\nacross 1.0 to 4.6 THz - 3.6 THz wide, 2.2 octaves - and arrives in a single pulse. One\nscan gives even quality across the band, with no favoured colour.\u003c\/p\u003e\n\u003cp\u003eThe HELIOS-HE laser delivers up to 2 mJ at 10 to 100 kHz, and the HYPERION-G-HE\ngas-filled multi-pass cell compresses it to a typical 29.2 fs at better than 90 %\ntransmission. That clean, round, few-cycle drive is what turns pump energy into peak\nterahertz field: above 10 MV\/cm the pulse does not merely look at a sample, it drives it.\u003c\/p\u003e\n\n\u003ch2\u003eKey highlights\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eFlat top, not a spike:\u003c\/strong\u003e 1.0 - 4.6 THz held within 10 dB, 2.2 octaves,\nusable span out to 12 THz.\u003cbr\u003e\n\u003cstrong\u003eAbove 10 MV\/cm\u003c\/strong\u003e in everyday operation with a guaranteed floor of\n8 MV\/cm - comparable to the field holding electrons to atoms.\u003cbr\u003e\n\u003cstrong\u003eField, not power:\u003c\/strong\u003e the peak field is measured by Kerr rotation in\ndiamond and has been cross-checked against an independent calibration on another source\nto within about 8 %.\u003cbr\u003e\n\u003cstrong\u003eFew-cycle drive:\u003c\/strong\u003e HELIOS-HE at 1 - 2 mJ compressed to a typical 29.2 fs\nin the HYPERION-G-HE multi-pass cell, with a round, single-lobed beam rather than the\nbutterfly profile familiar from OPA-driven sources.\u003cbr\u003e\n\u003cstrong\u003eTwo focus stations:\u003c\/strong\u003e 0.14 mm for the strongest field and 0.26 mm where\nthe sample needs room, with terahertz and laser cameras at both.\u003c\/p\u003e\n\n\u003ch2\u003eFour configurations on one bench\u003c\/h2\u003e\n\u003cp\u003ePump and probe can each be the terahertz pulse or the laser, and the bench is laid out\nso all four pairings are reachable without rebuilding it. The laser addresses electrons\nacross the band gap; the terahertz field addresses what moves slowly - carriers, phonons,\nspins, bonds.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eOptical pump, terahertz probe\u003c\/strong\u003e - a laser flash creates carriers and the\nterahertz pulse reads the conductivity that appears: photoconductivity, carrier lifetime,\ntransient screening.\u003cbr\u003e\n\u003cstrong\u003eOptical pump, optical probe\u003c\/strong\u003e - conventional transient absorption using the\ntwo laser arms already on the bench.\u003cbr\u003e\n\u003cstrong\u003eTerahertz pump, terahertz probe\u003c\/strong\u003e - the strong pulse drives the sample and a\nsecond terahertz pulse reads it: nonlinear terahertz response, field-driven phase changes,\nsaturation.\u003cbr\u003e\n\u003cstrong\u003eTerahertz pump, optical probe\u003c\/strong\u003e - the terahertz field distorts the sample and\nthe laser reads the induced birefringence.\u003c\/p\u003e\n\n\u003ch2\u003eWhat is included\u003c\/h2\u003e\n\u003cp\u003eSTFT flat-top terahertz source in the Terabullet enclosure, 120 x 90 cm footprint,\ndry-purged beam path with two focus stations.\u003cbr\u003e\nHELIOS-10W-HE or 20W-HE femtosecond ytterbium driver, 1 - 2 mJ at 10 - 100 kHz.\u003cbr\u003e\nHYPERION-G-HE gas-filled multi-pass-cell compressor, typical 29.2 fs output, optional\nhollow-core fibre cascade for few-cycle operation.\u003cbr\u003e\nMotorised delay line with 0.015 ps finest step, electro-optic sampling detection, lock-in\namplifier and optical chopper.\u003cbr\u003e\nReal-time terahertz camera with f\/0.7 imaging objective, plus built-in terahertz and laser\ncameras at both focus stations.\u003cbr\u003e\nControl and acquisition software, cabling and documentation.\u003c\/p\u003e\n\n\u003ch2\u003eApplications\u003c\/h2\u003e\n\u003cp\u003eNonlinear and high-field terahertz spectroscopy. Field-driven material control in\ntwo-dimensional materials, semiconductors and correlated systems. Ultrafast\noptical-pump \/ THz-probe carrier dynamics - the switch-on of a semiconductor shows more\nthan 90 % signal change with a sub-picosecond edge. High-dynamic-range THz-TDS material\ncharacterisation. Real-time terahertz imaging and non-destructive inspection through\nplastic, paper, ceramics and composites.\u003c\/p\u003e\n\n\u003ch2\u003eDelivery and acceptance\u003c\/h2\u003e\n\u003cp\u003eEvery unit is factory integrated, aligned and acceptance tested before shipment, then\ncommissioned on site, so the system is experiment-ready on hand-over. The performance\nfigures quoted here are commissioning measurements on this system with the beam path in\nopen air; purging the path raises them. Full measurement records, methods and\nuncertainties are available on request, and final figures are confirmed at on-site\nacceptance.\u003c\/p\u003e\n\n\u003c!-- wq-internal-links --\u003e\n\u003ch2\u003eComponents used in this system\u003c\/h2\u003e\n\u003cp\u003eThe subsystems below are the same parts WaveQuanta supplies individually, so a bench built around this platform can be extended or serviced from the standard catalogue.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/thz-off-axis-parabolic-mirror-oap2612-through-hole\"\u003eoff-axis parabolic mirrors\u003c\/a\u003e — the terahertz relay is built from these\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/thz-gap-electro-optic-sampling-crystal-110\"\u003eGaP electro-optic sampling crystals\u003c\/a\u003e — detection measures field, not power\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/rigi-s2x-thz-camera\"\u003eRIGI S2X real-time terahertz camera\u003c\/a\u003e — the imaging channel of this system\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/thz-optical-chopper-model-300cd\"\u003eoptical chopper\u003c\/a\u003e — paired with the lock-in amplifier\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/thz-fiber-optical-delay-line-odl\"\u003efibre-coupled optical delay line\u003c\/a\u003e — an alternative to the motorised stage\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"WaveQuanta","offers":[{"title":"Default Title","offer_id":49006541602970,"sku":"WQ-ITHZ-TK1","price":0.0,"currency_code":"SGD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0734\/6156\/3546\/files\/WQ-ITHZ-TK1-studio-card_e3bc4e3c-84a0-4e59-8555-178d083b90c9.jpg?v=1786691997"}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0734\/6156\/3546\/collections\/wq-terahertz-instruments-card.jpg?v=1786345975","url":"https:\/\/waveqvanta.com\/collections\/wq-terahertz-instruments.oembed","provider":"WaveQuanta","version":"1.0","type":"link"}