The GEMINI Interferometer is an advanced tool for fluorescence spectroscopy. It can be easily placed in between the sample and the detector to easily retrieve the SPECTRUM of your signal.
A pulsed laser excites the fluorescent sample; the signal is sent through the GEMINI and measured by a SPAD detector, which is connected to a TCSCP system.
A) Fluorescence Map of a sample (mixture of Rhodamine B + Nile Red in Ethanol) as a function of Emission Wavelength and Decay Time.
B) Vertical cuts along the map enable the visualization of dynamics at different wavelengths (vertical cuts in (A)).
C) Horizontal cuts along the map enable the visualization of spectra at different time (horizontal cuts in (A)).
Add GEMINI Interferometer in between the sample and the detector to easily retrieve the SPECTRUM of your signal.
With its 1 cm clear aperture, it is very easy to align the GEMINI into the optical setup.
The beam propagates straight inside the device, without encountering slits, gratings nor focusing elements, thus providing an exceptional efficiency over a broad spectral region.
The GEMINI does not cause any distortion in the spatial distribution of the beam, which is then very easy to be focused with a lens even on the smallest active areas of single-pixel detectors.
BEFORE the GEMINI
You can use an optical fiber to collect the signal from the sample. Use a coupler to couple the light out of the fiber, and send the collimated beam in free space inside the GEMINI.
AFTER the GEMINI
You can focus the light out of the GEMINI into an optical fiber, which can be directly connected to the detector. It is suggested to follow the same procedure of alignment reported here.
With its 1-cm clear aperture, the GEMINI features an exceptional light throughput, thanks to the absence of input/output slits and to the great system étendue (see the advantages of Fourier Transform approach here).
This provides an outstanding sensitivity to the entire optical system.
Measurements at different concentrations of the sample. The outstanding sensitivity of the system enables to reach picoMolar concentrations.
Details: Excitation Power: 275 μW @ 532 nm wavelength; Sample: Mixture of Rhodamine B and Nile Red in Ethanol.
The GEMINI guarantees an extremely high accuracy and reproducibility in the relative delay between the two generated phase-locked replicas of light.
This enables the measurement of very weak signals requiring long integration times, without worrying about the stability of the interferometer. In fact, GEMINI is completely insensitive to external vibrations or mechanical noises of the environment.
…With a MONOCHROMATOR
You need to replace the entrance slit with a thinner one.
This contributes to reduce the light throughput even more.
…With a GEMINI
You can change the spectral resolution any time, simply via software.
The high throughput is not affected when changing the spectral resolution.
The graph below shows the spectral resolutions provided by the 2 standard versions of GEMINI available, over the entire working spectral range. As in every Fourier-Transform-based approach, the spectral resolution is not constant as a function of wavelength.
The graph shows the minimum achievable spectral resolutions for each version of GEMINI (S and L).
If such spectral resolution is not needed, the user can select via software to perform
faster measurements with poorer spectral resolution.
NIREOS provides a plug & play software, capable of controlling both the GEMINI and TCSPC units from main manufacturers.
In this way, after you have set the spectral parameters of the GEMINI (e.g. spectral range and spectral resolution) and the temporal parameters of the TCSPC (e.g. integration time), you can directly acquire a fully calibrated TRES map with just one click.
Front Panel of NIREOS’ Software for TRES application.
(in alphabetical order)
Becker & Hickl GmbH:
• SPC-130-EMN (Tested)
• SPC-150 (Tested)
• All SPC family board (Compatible)
PicoQuant GmbH:
• PicoHarp300 (Tested)
• PicoHarp330 (Tested)
• TimeHarp260 (Tested)
• HydraHarp400 (Tested)
• MultiHarp (Tested)
Swabian Instruments GmbH:
• Time Tagger 20 (Tested)
• All Time Tagger boards (Compatible)
Tediel:
• Felix (Tested)
Universal Quantum Devices:
• Logic16 (Tested)
We are always prone to widen our portfolio of supported devices.
If you are interested to have support for a TCSPC not listed here, please contact us.
S. Wieghold et al., J. Phys. Chem. C (2020)
S. Wieghold et al., J. Mater. Chem. C (2020)
A. Perri et al., Optics Express 26, 2270-2279 (2018)
