EOS Fire
Nanosecond Transient Absorption Spectrometer
EOS Fire is the next generation, fully automated spectrometer in the EOS family. It is a unique (Patent No.: US 7,817,270 B2) broadband pump-probe sub-nanosecond Transient Absorption Spectrometer designed to work with a wide variety of pulsed lasers. A complete turn-key system, EOS Fire measures transients with sub-ns time resolution over a large, adjustable time window. At any time, the EOS Fire time resolution can be improved to femtosecond by integrating it with HELIOS Fire, our broadband pump-probe femtosecond transient absorption spectrometer.
Broad probe spectral range
350 – 950 nm
800 – 1600 nm
1600 – 2200 nm
Spectral resolution optimized for transient absorption
For transient absorption higher spectral resolution is not always better. It is important to map out all the spectral features, but it is also critical to deliver enough probe light to each pixel of the detector. These two parameters counteract, and it is necessary to balance them. With not enough probe light the full sensor dynamic range will not be utilized the data will be noisy; and with not enough spectral resolution important species or processes can be missed. This is why we configure the spectral resolution sufficient for resolving what is practical in condensed phase experiments, but not excessively high to allow for enough probe light intensity on the detector.
Spectral Range Intrinsic spectral resolution Spectral resolution with a 200 µm slit (recommended) UV-VIS
2 nm
4 nm
NIR
5 nm
13 nm
SWIR
5 nm
13 nm
Sub-ns resolution with a virtually unlimited time window
In contrast to conventional flash photolysis based on the continuous photoelectric method, EOS is pump-probe spectrometer. It utilizes a sub-nanosecond pulsed probe light source – a PCF (photonic crystal fiber) based supercontinuum laser. The pulse duration of this probe light source determines the time resolution of the spectrometer (< 1 ns) and eliminates the need for fast photodetectors.
In EOS the pump-probe delay is controlled electronically, and the maximum time window is very close to half the repetition period of the pump laser. The maximum time window can be calculated as: (pump laser repetition period)/2-100 µs. For example for 1 kHz pump lasers it is 400 µs. The window can be easily extended by lowering the pump laser repetition rate.
Large sample area – 300 mm x 300 mm
The spacious sample compartment allows for easy mounting of various cryostats and temperature-controlled sample holders. Also, simply having more space around the sample makes working with your samples simpler.
The lowest probe and pump power through the sample
Focusing the probe tightly into the sample allows to drastically reduce the laser energy required for photoexcitation. This is critical for minimizing the sample photodegradation. The unique beam characteristics of the EOS PCF-based probe light source allow us to focus the probe light into a small area – in the standard configuration the EOS probe beam waist in the sample is ~30 µm. As a result, the typical excitation energy required for EOS is hundreds of nJ/pulse. Additionally, this beam size permits studying very small samples.
Various automation options, including full automation
Automated Pump Beam Alignment. The EOS Fire software ensures continuous optimal overlap of the pump and probe beams in the sample with <10 µm precision.
Automated switching between UV-VIS, NIR and SWIR spectral ranges
Detectors
All Helios/Eos Fire detectors are fiber-coupled spectrographs with linear array detectors. Each spectrograph has an aberration-corrected concave grating for maximum light throughput (essential for high quality data). The ADC resolution is up to 16 bit. All detectors are mounted in a 19” electronics rack outside the optical bench.
UV-VIS. We have two detector options for this spectral range:
CMOS. This 1024 pixel CMOS sensor is ideal for higher speed data acquisition. Allows for individual laser pulse detection for up to 5 kHz. Spectral response: 200 – 1000 nm. Typical spectral range spans 600 nm (ie. 350 – 950 nm).
CCD. This 2048 pixel back-thinned CCD sensor is ideal for 1 – 2 kHz lasers and features very high sensitivity as well as the dynamic range. Spectral response: 200 – 1000 nm. Typical spectral range spans 600 nm (ie. 350 – 950 nm). Spectral acquisition rate – up to 2000 spectra/s.
NIR spectral range. This 256 pixel InGaAs sensor presents a great balance between spectral resolution and sensitivity. Spectral response: 800 – 1600 nm. Typical spectral range spans 800 nm (ie. 800 – 1600 nm). Spectral acquisition rate – up to 5000 spectra/s.
SWIR spectral range. 256 pixel InGaAs sensor (spectral response: 1000 – 2600 nm). Typical spectral range spans 800 nm (ie. 1600 – 2200 nm). Spectral acquisition rate – up to 5000 spectra/s.
Modular design
Magnetic stirring allows for working with sealed cuvettes (≥2 mm long) while the translating sample holder can raster thinner cuvettes that cannot be stirred, films, wafers, etc. The two sample agitation modes are easily interchangeable without having to unbolt or realign any components.
Optical bench:
W356 x L915 x H250 mm
Electronics rack:
W534 x L610 x H686 mm
Various sample holder options
Magnetic stirring allows for working with sealed cuvettes (≥2 mm long) while the translating sample holder can raster thinner cuvettes that cannot be stirred, films, wafers, etc. The two sample agitation modes are easily interchangeable without having to unbolt or realign any components.
Probe reference
EOS comes standard with a two-channel probe or “probe reference”. In this approach the probe beam is split into two before passing through the sample. While one arm travels through the sample, the other is sent directly to the reference spectrometer that monitors the fluctuations in the probe beam intensity. The main advantage of this technique is that it allows the user to achieve the specified signal-to-noise ratio with a lower number of averaged laser pulses. This is important because EOS’s time window spans from nanoseconds to sub-milliseconds with the typical number of time points of >1000. When integrated with HELIOS it automatically adds the “probe-reference” feature to the HELIOS.
Optional computer-controlled filter wheel
for varying pump energy, etc.
EOS Fire features versatile and user-friendly LabVIEW based software for instrument control and data acquisition. The software allows for full experiment automation, so no input from the user is required for the whole experiment duration.
The data acquisition software features:
Automated alignment of the pump beam
Computer controlled switching between UV/VIS, NIR, and SWIR modes.
Supports computer controlled translating sample holder.
Supports pump beam shutter.
Supports motorized filter wheel for automated pump intensity control.
User specified initial step size, time window and the total number of time steps.
Pseudo-random scanning of the pump-probe delay times averages out low frequency noise.
Real-time histogram plotting to show the sampling distribution over the time window.
Built-in algorithms for automatic equalizing of the sampling distribution over the whole time window.
API (Application Programming Interface) for EOS Fire is provided for further experiment customization and integration with external
商品属性 [波长范围] 350 – 2200 nm [光学分辨率] 2-13nm