Page Type: Customer Story

X-ray Beam CharacterisationCustomer Stories

Dr. Roelof van Silfhout

The Department of Chemistry, KU Leuven, Belgium

Background

Dr. Roelof van Silfout is a researcher at KU Leuven, working on a variety of projects mostly concerning x-rays. Dr van Silfout explained one of his experiments, “We are interested in defining or measuring the position of a hard x-ray beam. We have an indirect detection system where we use a very high-resolution scintillator material that is lens-coupled to a camera, so the camera is focused on the back of the scintillator while the x-rays enter from the front. The camera is then at a 45° angle from the light path to avoid any damage to the camera sensor. We measure back-reflected x-rays, these reflected x-rays have a very low intensity, 7 orders of magnitude less intense than the x-ray beam itself.

Dr van Silfout’s research interests involve the application of x-rays in structural studies of materials at the atomic scale, as well as optical characterization of these x-ray beams. With a role at both KU Leuven and the European Synchrotron Radiation Facility (ESRF, France), Dr van Silfout has a strong track record of innovation and experimentation with high-precision instruments for x-rays.

Figure 1: Horizontal x-ray beam focusing with the Kinetix22 sCMOS. The top row shows graphs of the row summation of each corresponding image below, the solid line indicating horizontal x-ray beam profile and dashed line indicating vertical (only the horizontal plane is being focused. The bottom row shows images of x-ray beam adjustment taken with the Kinetix22 sCMOS. The label r’ indicates the radius of curvature of the mirror above and below the optimum of 693 nm.

Challenge

X-rays detected by the camera are of an extremely low intensity, requiring a highly sensitive camera in order to have a sufficient signal-to-noise ratio to detect the x-ray beam scatter. Dr. van Silfout told us about the challenges he encounters, “We typically have to sum the detected signal and perform procedural background reduction in order to detect these x-rays… Because the x-rays have low signal levels, this pushed us towards using dedicated cameras with low noise, I’m always on the lookout for cameras which have good performance, high sensitivity, and fast readout.”

“I got very interested in sCMOS, I usually do photon transfer curves to measure camera performance. However, some sCMOS cameras have two different gain amplifiers which are merged by software, and somewhere in the middle there can be huge anomalies which are really awkward when collecting high dynamic range images, introducing artificial issues.”

I looked at other sCMOS cameras, for me it was a no-brainer to pick the Kinetix22. I’m very happy with it, it really does what it promises.

Solution

The Kinetix22 sCMOS is a powerful solution for indirect x-ray imaging, equipped with sub-electron read noise levels that ensure even the weakest x-ray signals can be reliably detected. Dr. van Silfout described his experiences with the Kinetix22, “For me, the reasons the Kinetix22 was a good choice was that it perfectly matches our aperture at 22 mm, it has the really low noise characteristics that we were looking for, it is very fast, and the range of readout options and software compatibility is really useful when you need to synchronize your imaging setup.”

“The 22 mm FOV was a very good selling point as it matches our C-mount microscopes, the small 6.5 um pixel size was also a very strong point, as it gave us a high resolution… I also like the ability to make multiple regions of interest around the sensor, you can do it very nicely in software control, it’s very fast if not simultaneous.”

“The photon transfer curves with your cameras did not have the anomalies we would usually see with other sCMOS… I looked at other sCMOS cameras, for me, it was a no-brainer to pick the Kinetix22. I’m very happy with it, it really does what it promises.”

“The support I got from Photometrics from my initial contact was excellent, looking at the whole picture in terms of software support, the features of the camera, and of course the price, for me it was definitely a no-brainer. I can’t think of a reason not to buy it!”

Single-Molecule FRETCustomer Stories

Prof. Keith Weninger

Department of Physics, North Carolina State University, US

Background

The lab of Prof. Keith Weninger develops single-molecule fluorescence methods to study biomolecular systems, with a particular focus on FRET to study proteins involved in DNA mismatch repair. Prof. Weninger further explained his research, “I do single-molecule FRET experiments on tethered DNA molecules with surface-immobilized TIRF microscopy.”

“Most of our lab is focused on DNA mismatch repair. After copying DNA, the DNA polymerase has an error rate, and a set of proteins follow behind and proofread, repairing any base-base mismatches. DNA polymerase makes a mistake one in every million bases, and the proofreaders improve this by a factor of a thousand, resulting in one in a billion errors from DNA copying in cells. We are interested in these proteins and how they work, and when they don’t work right it’s associated with various cancer phenomena.”

“We do different things, such as build short DNA molecules with mismatches and tether them to a surface and flow the proteins over them. Or we can put a polystyrene bead onto tethered DNA to see the motion and range. For our FRET imaging, we can put FRET fluorophores on the DNA, protein or one on each.”

Figure 1: Top image shows two Prime 95B sCMOS cameras on a Cairn TwinCam for simultaneous multichannel imaging. The bottom images are FRET for the red laser excitation, showing the acceptor channel (left) and donor channel (right), each acquired by a separate Prime 95B.

Challenge

This format of single-molecule microscopy can be highly challenging, due to the combination of a very low signal level and the need for high-speed imaging in order to capture molecular dynamics. Prof. Weninger described his need for speed, “In every experiment we want to push temporal resolution, we basically always work at the limits of technology and so we want to image as fast as we can to capture conformational dynamics and interaction, using sub-millisecond exposures. There are also a variety of different timescales so we need to be flexible.”

“We are at a very low signal, photon-counting level as we are doing single molecule fluorescence. We can increase the intensity of the light source but this can result in bleaching, so we also need good triggering of experiments to minimize bleaching too.”

I looked at other sCMOS cameras, for me it was a no-brainer to pick the Kinetix22. I’m very happy with it, it really does what it promises.

Solution

The Prime 95B sCMOS is an ideal solution for high sensitivity single-molecule microscopy, featuring near-perfect 95% signal collection thanks to back-illumination, low noise levels, along with a large 11 μm ideal for high magnification molecular imaging work.

Prof. Weninger described his imaging experiences, “We set up two Prime 95Bs on a TwinCam and they produce comparable data to our previous EMCCDs. We were using them for slow imaging but now we can go fast. We can also use the TwinCam for polarization.”

The use of two cameras allows for high-speed, high-throughput FRET imaging, with specifications well matched for a highly sensitive TIRF imaging system.

Live-Cell Single-Molecule FluorescenceCustomer Stories

Prof. Christof Gebhardt, Mr. Devin Assenheimer

Institute of Biophysics, Ulm University, Germany

Background

Prof. Christof Gebhardt, along with PhD student Devin Assenheimer and the team from Ulm University told us about their research. “We perform single-molecule fluorescence microscopy both in vitro and in vivo within cells, with the aim to also image small organisms. We use a light sheet-like illumination scheme where the sheet thickness can be set using a pinhole. This, in combination with organic dye fluorescent labels, gives us sufficient signal to noise for single-molecule detection even at very high temporal resolutions. We can basically image almost anywhere in a cell, we often image a couple of microns above the glass surface.”

“With live cell single-molecule experiments, we can measure the kinetics of biological molecules. For example, we can look at molecular motors and investigate how they move and measure their velocities. Conditions used in vitro with purified proteins create an artificial environment, so velocities measured in vitro might be different than what is happening in vivo in the live cell.”

Figure 1: A single molecule within a live cell imaged using single-molecule fluorescence with the Prime BSI sCMOS. The molecule in question is a molecular motor, with the motion indicated by the pink tracking line.

Challenge

Traditional single-molecule fluorescence microscopy of fixed cells carries its own challenges, using live cells introduces additional complexity. Prof Gebhardt explained further, “Live cells cannot be permeabilized and cleared to minimize autofluorescence. Thus the background is higher compared to imaging in fixed cells.”

“To image single molecules, we need the spatial resolution high enough to distribute the fluorescent signal over a couple of pixels on the camera sensor. Therefore the magnification is such that we only have one cell in the field of view.”

“Another challenge is that live cells do not tolerate high laser power. To measure molecular kinetics, we typically want to go to a high temporal resolution of 100 Hz, so 10 ms exposure. Since we cannot increase the laser power above a critical value, this means the signal of a single molecule is only a few hundred photons. Thus, we are interested in a low read noise in order to get a good signal-to-noise ratio.

”This application requires a robust and flexible imaging device that can image with high sensitivity without losing spatial or temporal resolution, all at a high speed and across a large field of view.

I looked at other sCMOS cameras, for me it was a no-brainer to pick the Kinetix22. I’m very happy with it, it really does what it promises.

Solution

The Prime BSI sCMOS is the ideal solution for this application, with low overall noise and a large camera sensor with a small pixel size. Prof. Gebhardt described his experiment with the Prime BSI, “Before, we were working with EMCCD cameras due to the high signal to noise, but now we feel that the sCMOS takes over in that respect. We can also benefit from higher temporal resolution even in a low-light application. We can make the regions of interest small and go for a very high speed.”

“The big advantage of these sCMOS cameras is the high framerate possible with low signals. One of the reasons we got the Prime BSI was because it is fast with a large field of view, along with the low noise levels.”

Mr. Assenheimer spoke in terms of software and ease of use, “We are using the Prime BSI with MicroManager, the experience with the camera is good, really easy to implement. I’ve worked with it for a while now and not experienced problems.”

The Prime BSI sCMOS also allows for future improvements of experiments, with the large field of view and advanced hardware triggering systems allowing for simultaneous multifocal or multichannel imaging when paired with a splitter.

Single Molecule Localisation MicroscopyCustomer Stories

Prof. Rainer Heintzmann and Alexander Jügler

Biological Nanoimaging, Leibniz Institute of Photonic Technology (Leibniz-IPHT)

Background

Senior Ph.D. student Alexander Jügler works in the Heintzmann Lab, which studies super-resolution imaging applications such as single-molecule localization microscopy (SMLM), and works on improving the phototoxicity and resolution of such techniques while making them easier to work with.

As Mr. Jügler mentioned, “In my imaging, I create local minima and shift them by a few nanometers using a spatial light modulator. We are able to detect the nanometer shift but to evaluate the local minima quality we need to find stable and bright fluorescent particles a few nanometer in size. The 110 nm microbeads we are using right now are way too big.

“Later we will use all kinds of biological samples with the intent to develop a system that is able to analyze toxic fungi, which create pores a few nanometres in size.”

Figure 1: An image of the Prime BSI CMOS on an optical bench, set up for single molecule localisation microscopy in the lab of Prof. Rainer Heintzmann.

Challenge

When performing super-resolution imaging, especially for SMLM, it is vital to have a high signal-to-noise ratio in order to best detect these particles. This requires both maximizing the signal collection with a high quantum efficiency and balanced pixel size, as well as minimizing the noise level with low read noise.

In addition, Mr. Jügler stated, “A big field of view to track the particles is also needed, a big advantage of our technique is that we have to track across a big FOV.” As the imaging system and technique can make use of a large FOV, it would be best paired with a camera that also features a large sensor size.

I looked at other sCMOS cameras, for me it was a no-brainer to pick the Kinetix22. I’m very happy with it, it really does what it promises.

Solution

The Prime BSI has a remarkable signal-to-noise ratio due to the near-perfect 95% quantum efficiency and the extremely low read noise, all while running at a high speed with a large sCMOS field of view. This makes the Prime BSI a great solution to SMLM imaging.

As outlined by Mr. Jügler, “I am working in this super-resolution field and trying to implement these techniques, which is why I need very good cameras with high quantum efficiency, and are very fast and do a good job at high speed. In our lab, we have a number of cameras available and I have decided on the Prime BSI because it has these characteristics.”

“My overall statement is that the [Prime BSI] is very good for my experiments. For me the experience of the camera and the quantum efficiency was great. Many students want to have a camera and I was lucky to get it! It’s one of the best cameras in our lab right now.”

The Prime BSI is running in MATLAB in the Heintzmann lab and Mr. Jügler mentioned how easy it was to implement the Prime BSI in the system with this software.

Spectral Optical Coherence TomographyCustomer Stories

Prof. Aart Verhoef

Department of Soil and Crop Sciences, College of Agriculture & Life Sciences, Texas A&M University, US

Background

The Verhoef Lab designs novel laser light sources to enhance existing and support novel imaging methods. Their systems might result in signals ranging from the detection of a few photons for super-resolution imaging, through to differentiating small differences amongst many tens of thousands of photons.

One lab focus is optical coherence tomography (OCT), which uses the ability of light to interfere with itself to map structures in tissues. Spectral OCT uses multiple colors of light to map a tissue in depth all at once.

Figure 1: Bessel beam OCT setup. The spectrometer uses a Prime 95B sCMOS camera to acquire spectra with a high spectral resolution and frame rate. Using a Bessel beam, the depth of focus of the setup is more than doubled compared to a Gaussian beam setup.

Challenge

Spectral OCT generates a map of the position in depth, but in one shot measurement. The changes in intensity due to interference of a broad-band input source when unmixed mathematically give the same results as when moving the reference arm.

Spectral OCT uses broad-band light sources centered around 1 μm for good tissue penetration. Strong focusing of the light in the sample arm results in a high lateral resolution in the focal plane of the focusing lens, but this resolution deteriorates fast away from the focus. In order to improve the lateral resolution away from the focal plane of the OCT scan lens, the Gaussian beam illumination can be replaced by Bessel beam illumination, at the expense of optical losses.

With less power returned from regions of the sample, a camera with a large dynamic range, high sensitivity, and a large chip size is needed in a custom-built spectrometer.

Typically, a camera with only a few lines of pixels is used in such spectrometers. However, when working with Bessel beams (which have a pi phase-shift between the central peak and the surrounding weak ring), such cameras do not allow to distinguish between a phase-shift across the vertical direction of the beam and the absence of fringes.

I looked at other sCMOS cameras, for me it was a no-brainer to pick the Kinetix22. I’m very happy with it, it really does what it promises.

Solution

The Prime 95B meets the requirements for a camera with a large dynamic range, large field of view, and high sensitivity.

Prof. Verhoef told us about the Prime 95B CMOS, “The Prime 95B offers a pixel size of 11 μm, that allowed us to construct a compact spectrometer matching the spatial resolution of the OCT imaging system without dramatically oversampling the resolution. The large chip size of the 95B almost exactly matched the spectral extent of our broad-band Bessel beam light source. The high frame rates that can be achieved with the 95B allow us to obtain high-resolution OCT images within a short time. The 95B allowed us to demonstrate a substantial improvement of focal depth provided by Bessel beam OCT.”

Novel Hyperspectral ImagingCustomer Stories

Prof. Silas Leavesley

Department of Chemical and Biomolecular Engineering, University of South Alabama, US

Background

The interdisciplinary laboratory led by Prof. Silas Leavesley and Dr. Thomas Rich is working to develop novel hyperspectral imaging systems for microscopy and endoscopy. Using rapidly controllable light sources with precise spectral selection they aspire to be able to increase the number of individual sensors and probes detected concurrently. This will allow measurements of spatial and temporal fluctuations in various signal transduction cascades in cells, tissues, and organisms.

Figure 1: Spectral excitation-scanning images of a 6-label slide (Abberior with autofluorescence). Excitation wavelengths were sampled over a range of 360-540 nm, at a 5 nm increment, using a Xe arc lamp and Sutter VF 5 filter assembly equipped with Semrock VersaChrome filters, while image data were acquired using a 555 nm long-pass emission filter and Prime 95B sCMOS camera. The raw fluorescence signal can be visualized as Total Fluorescence (the summed intensity across all wavelength bands) or RGB false-colored (a visualization of 3 selected and false-colored wavelength bands). A spectral library was constructed from single-label controls (plot at right). The spectral image cube was then unmixed using non-negatively constrained linear unmixing. The residual (unaccounted for) signal is displayed as both total signal, called root-mean-square (RMS) Error, and the relative error, as a percent of the RMS signal in each pixel, called RMS % Error. Linearly unmixed images were false colored for visualization and were also merged, shown by the False Colored Unmixed.

Challenge

Acquisition of hyperspectral image data on timescales relevant to biochemical and cellular processes requires rapid selection of precise excitation wavelengths and rapid, low-noise image acquisition of resulting excitation-scanning spectral image stacks.

Given the aim of acquiring 1-5 spectral image data sets of 30 wavelength bands each second, a fast, sensitive low-noise camera is an absolute requirement to generate data of sufficient signal-to-noise ratio for interrogating cellular processes.

Previous work using widefield imaging with EMCCD cameras was successful, but the field of view and slow readout speed of EMCCD detectors limited the spatial and temporal sampling of the desired measurements. Now, Prof. Leavesley’s lab is aiming to acquire similar spectral data using spinning disk confocal microscopy to allow 3D, timelapse, and spectral imaging capabilities.

I looked at other sCMOS cameras, for me it was a no-brainer to pick the Kinetix22. I’m very happy with it, it really does what it promises.

Solution

The Prime 95B is a highly sensitive CMOS camera with a large field of view, matching a near-perfect 95% quantum efficiency with low read noise for a high signal-to-noise ratio when imaging.

Prof. Leavesley told us about his experience with the Prime 95B CMOS, “The Prime 95B, with its high quantum efficiency, large FOV, high readout speed, and low readout noise allowed us to gather spectral cubes at N spectral volumes per second, image cubes at >1 Hz frequencies, and will be a key component in developing future 5-dimensional imaging approaches.”

OpenSPIM for Cleared Fish BrainCustomer Stories

Dr. Franziska Curdt, Ms Laura Ziegenbalg

Institute for Biology and Environmental Sciences, University of Oldenburg, Germany

Background

Dr. Franziska Curdt and PhD student Laura Ziegenbalg use fluorescent microscopy techniques to investigate the magnetic senses of fish, namely the magnetic imaging of putative magnetoreceptors. To this end, Dr. Curdt has built several imaging systems to image large tissue samples, including a magnetoscope and an OpenSPIM-based light-sheet microscope.

Dr. Curdt told us about her research, “We are imaging volumes of cleared tissue in order to find out more about the magnetic sense of certain species, as the origin of this sense is still a bit enigmatic”

Ms. Ziegenbalg explained the choice of sample, “We want to find out how fish can perceive the Earth’s magnetic field, this involves finding brain regions that correlate with magnetic stimuli and building a reference brain atlas. While this atlas exists for zebrafish, these fish are not migratory and it is not established if they can sense the Earth’s magnetic field, so we are building a 3D atlas for the migratory rainbow trout.”

Figure 1: 3D reconstruction of a cleared zebrafish brain from three different perspectives, imaged with the Prime BSI Express. The size of the brain is approximately 5 x 2 x 1.5 mm.

Challenge

While light-sheet microscopy with zebrafish is well established and often used as a model organism or to optimize imaging protocols, work with rainbow trout is less common. While the zebrafish brain is on the millimeter scale, the brain of the rainbow trout is many times larger, up to 2 cm. This large-format tissue imaging requires a large camera sensor in order to avoid excessive tiling and stitching.

In order to use the full aperture of the 4x objective, a small pixel is needed in order to achieve sub-cellular spatial resolution and optimize for Nyquist at low magnifications.

I looked at other sCMOS cameras, for me it was a no-brainer to pick the Kinetix22. I’m very happy with it, it really does what it promises.

Solution

The Prime BSI Express sCMOS features a small pixel and a large pixel array, allowing for large images to be obtained that feature high resolution at low magnifications. The high signal collection and low read noise of the Prime BSI Express maximize the signal-to-noise ratio and result in high-quality images, suitable for quantitative imaging and the construction of a 3D brain atlas.

Dr. Curdt described their experience with the Prime BSI Express, “The small pixel size of the Prime BSI Express combined with the relatively large sensor is a big advantage. We are also planning a future application involving calcium imaging. We got the Prime BSI Express with this in mind so we can do fast recording due to the high imaging speeds.”

“It was simple to get the Prime BSI Express set up in MicroManager, it worked immediately. No difficulties, no problems. I also really like the customer service of Teledyne Photometrics.”

Delayed Fluorescence ImagingCustomer Stories

Dr. Anthony Hall

Anthony Hall Group, Earlham Institute, University of Norwich, UK

Background

The Anthony Hall group is a world-leading lab with a focus on understanding wheat genomics. Their work seeks to bridge the gap between traditionally used model plant organisms and crop species with real-world applications.

The biological circadian clock is the internal time-keeping mechanism within a living organism. It is entrained by external day-night cycles and is responsible for controlling a wide array of processes such as photosynthetic activity. A robust circadian rhythm is vital to overall plant fitness and controls many other factors such as flowering time and resistance to pathogen attack.

A valuable tool available to researchers who are investigating photosynthesis is to observe bioluminescence. The Anthony Hall group is interested in a form of bioluminescence called delayed fluorescence (DF), whereby photons of light absorbed by the plant are later re-emitted at a level proportional to the photosynthetic efficiency of the sample at that precise time. This measurement cycles with a circadian rhythm and can be used on any biological sample containing photosynthetic pigments. An advantage of DF over conventional luciferase experiments is that material can be used straight from the plant with no genetic modifications necessary.

Figure 1: Delayed fluorescence image of wheat leaves taken with the Retiga LUMO. A) Delayed fluorescence in 3 week old wheat leaves (cv.Cadenza) with a 60 second exposure time. B) Images 6h, 12h, 18h, and 24h after perceived dawn show the signal variation with the circadian rhythm. C) Normalized data for DF intensity over 3 days.

Challenge

DF has a very weak intensity compared to other forms of bioluminescence and requires long exposure times to capture all available signal. Image acquisition is triggered after a critical pause following lights-off to eliminate contamination from residual light and other forms of bioluminescence.

The primary challenge is to obtain a bright enough signal over several days for meaningful quantitative measurements of the oscillations to be made. Having a sufficient field of view for high throughput sample analysis is also important. Accuracy of camera shutter speed is essential for capturing all available DF signal without any noise from the light source turning off.

The previous technology used for delayed fluorescence measurements was based on expensive back-illuminated CCD cameras, which required cooling down to ~70°C to reduce dark current. The large pixels of these sensors also reduced resolution. These cameras significantly increase the cost of putting together and running a delayed fluorescence experiment.

I looked at other sCMOS cameras, for me it was a no-brainer to pick the Kinetix22. I’m very happy with it, it really does what it promises.

Solution

The Retiga LUMO CCD camera from Teledyne Photometrics is precisely engineered to have low dark current at long exposure times, low noise readout, and to account for hot pixels. As a result, the Retiga LUMO provides equal or better performance than a back-illuminated CCD for a fraction of the cost. What’s more, the larger sensor with smaller pixels improves both field of view and resolution over the previous technology.

“With the Retiga LUMO, we get consistent image quality, no extra cooling is needed and we no longer need to wait an hour for the cameras to cool down,” says Dr. Anthony Hall, head of plant genomics. “We were able to use the same protocols in the Micro-Manager software, making it easy to get the cameras up and running.”

Gene Expression via Bioluminescent ReportersCustomer Stories

Dr. James Locke, Mr Mark Greenwood

The Locke Group Laboratory, University of Cambridge, UK

Background

The research performed by the Locke Group at the University of Cambridge focuses on developing a quantitative understanding of gene circuit dynamics. One of the gene circuits of particular interest is the circadian clock, the biological timekeeper. In plants the clock is highly important; the clock controls anticipation of day/night as well as responses to faster environmental changes.

The research team has found it is critical to observe the circadian clock at both the tissue level and single-cell level as traditional approaches that take an average from a population can obscure heterogeneous responses and novel dynamics.

Figure 1: Expression of GI:LUC, a transcriptional reporter for the circadian clock, in single Arabidopsis seedlings. The image was taken using the Retiga LUMO with a 20 minute exposure and 4×4 binning.

Challenge

Previously the team used luminescent reporter genes and EMCCD or back-thinned CCD cameras to monitor gene expression of the clock tissue specifically over several days. Although long exposure imaging with these cameras provides good signal sensitivity, often much of the spatial dynamic was lost to noise. The cost and physical size of the cameras also limited their throughput.

I looked at other sCMOS cameras, for me it was a no-brainer to pick the Kinetix22. I’m very happy with it, it really does what it promises.

Solution

In an effort to better support their imaging needs, the team
purchased four Retiga LUMO™ CCD cameras from Teledyne Photometrics. Mr. Greenwood (Ph.D. student) shares, “We chose the Retiga LUMO camera because of its impressive sensitivity and low dark current which means we can achieve a high signal while minimizing noise, which is the key to long exposure imaging.”

Greenwood continues, “The low cost and physical size of the Retiga LUMO in comparison to other cameras designed for long exposure imaging, as well as the simple API, meant that we could increase our throughput considerably.”

Quantum Simulation via Atomic Optical LatticesCustomer Stories

Alexander Impertro, Julian Wienand, Prof. Monika Aidelsburger

Quantum Optics Group, Ludwig-Maximillian University of Munich, Germany

Background

Alexander Impertro and Julian Wienand are both PhD students in the group of Prof. Monika Aidelsburger and Prof. Immanuel Bloch at the LMU Munich, working on experiments with ultra-cold atoms for analog quantum simulation.

They took us through the concepts behind their work, “The idea is that by taking very cold atoms and trapping them in lattices generated by interfering laser beams, one can simulate the behavior of electrons in a real solid. The atoms hereby play the role of the electrons and the potential landscape generated by the laser beams mimics the ion crystal. This effectively simulates quantum phenomena in real solids with the benefit that the atoms can be controlled in a targeted way, as typical length scales in the analog quantum simulator are thousands of times larger than in real solids.”

“The quantum simulator is highly tunable. By changing the depth of the lattice and the value of an external magnetic field, the dimensionality of the lattice, the strength of the atom tunneling, or the magnitude of the interactions can all be adjusted, in order to simulate tailored systems and phenomena.”

The Quantum Optics Group requires an imaging setup in order to determine which site of their lattice is occupied with atoms and which site is not. In order to do this, the lattice intensity can be increased to ‘freeze’ the atoms in place, then near-resonant lasers can be used to excite the atoms, these atoms then fluoresce and the scattered photons can be detected with a camera.

Figure 1: Fluorescence image of ultra-cold cesium atoms pinned in an optical lattice, taken
with the Kinetix22 sCMOS.

Challenge

Mr. Impertro and Mr. Wienand described the challenges they face, “Exciting the atoms with our laser heats them up and will cause them to move, so the atoms only fluoresce for around 100 milliseconds to 1 second before they tunnel to another site of the lattice. During that time, we need to acquire an image where we see the single atoms in their lattice sites. In order to get high signal-to-noise ratios, we require high quantum efficiencies and low electronic noise combined with a high frame rate.”

“The better the signal to noise ratio, the shorter we have to image in order to get the same image quality, so what’s important is that the camera has low noise. In order to carefully analyze the quality of the imaging technique, it is also important to take many images of the same atom cloud. Typically, we want to take 10 or more images at exposures of 100 ms each and a small delay between them.”

Another challenge is that the detected wavelength is in the near-infrared (NIR) region of the spectrum, at 852 nm. This means a camera with a broad QE range and good NIR sensitivity is required in order to achieve good signal-to-noise ratios. For high-quality and high-resolution images it is further beneficial to work with small pixel sizes in order to reduce the complexity of the optical setup. Moreover, having a large sensor available significantly simplifies finding a first signal from the atomic cloud, thereby simplifying experimental alignment procedures.

I looked at other sCMOS cameras, for me it was a no-brainer to pick the Kinetix22. I’m very happy with it, it really does what it promises.

Solution

The Kinetix22 sCMOS is a flexible and powerful camera with numerous physical science applications, particularly for quantum-based projects. The large 22 mm sensor, fast readout speeds, small pixels, and sub-electron read noise result in an ideal solution for this application.

Mr. Impertro and Mr. Wienand told us about their experience with the Kinetix22, “Previously, we used a camera with much longer readout times, around 800 ms. Compared to this the Kinetix22 is a huge improvement for us as we can take several measurements of the same cloud one after another.”

“We found that the Kinetix22 Sub-Electron mode gave us a great signal-to-noise ratio, so we plan to use this mode in the future for our experiments. What we also like about the Kinetix22 is that the pixel size is small, so we don’t need to work with large magnifications. A previous camera with 13 μm pixel size meant we had to use a magnification of at least 100x, now thanks to the 6.5 μm pixel size of the Kinetix22 we can use 40-60x, which makes our imaging path much shorter.”

“The 22 mm chip size is also much larger than our previous camera and this makes it much easier to find the atoms in the system, which is very useful. We used the USB connector with the Kinetix22, this was really easy plug and play, this was something we liked a lot.”