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Cathodoluminescence for bulk and nanostructured Gallium Nitride-based LED materials
Gallium Nitride (GaN) is a versatile wide-band gap semiconductor…
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Product Overview
The Delmic SPARC Spectral cathodoluminescence (CL) system has been developed to provide researchers with the most comprehensive and sophisticated tool for the characterization of nanoscale materials. Its modular design allows users to customize and tailor the system to their specific research needs, enabling the selection of optical modules and interchangeable components that facilitate advanced imaging modes. The system prioritizes precise and rapid measurements to ensure optimal reliability across a wide range of applications.
Thanks to its high light collection efficiency, spatial resolution, and compatibility with a diverse range of scanning electron microscopes, the SPARC Spectral system has found widespread utility in the field of materials science. Its versatile capabilities make it well-suited for a range of applications, from the characterization of semiconductor materials and the examination of optoelectronic materials like LEDs, to the analysis of geological rocks and minerals. In every aspect of CL imaging, the SPARC Spectral system excels, delivering exceptional performance and unparalleled insights into the properties and behavior of nanoscale materials.
Advanced CL Imaging Modes for Electron Microscopy
Time-resolved imaging, angle-resolved imaging, hyperspectral imaging, RGB and panchromatic intensity imaging, polarization-filtered imaging, and lens scanning energy momentum imaging at your disposal.
Modular CL Design
Modify the SPARC Spectral with exchangeable optical modules, gratings, and mirrors
Automated Mirror Alignment
Collect reproducible and comparable measurements with a fully motorized mirror stage
SPARC Spectral Features
The SPARC Spectral system offers researchers a broad range of advanced imaging modes, each capable of providing unique and valuable insights into the properties and behavior of nanoscale materials. With the ability to extend the system to perform more specialized CL imaging modes, either independently or in combination, researchers can gain an even deeper understanding of the samples they are studying. For example, angle-resolved and polarization-filtered CL imaging can be used in tandem to reveal detailed information about the spatial and directional distribution of luminescence intensity, shedding light on the complex interactions between light and matter at the nanoscale.
These diverse imaging modes serve to enhance the depth of knowledge gained from SEM characterization, complementing other detection modalities such as backscattered electron/secondary electron detectors and energy dispersive X-ray spectroscopy (EDS). By leveraging the full capabilities of the Delmic CL system, researchers can gain a comprehensive and multi-faceted understanding of the properties and behavior of the materials they are studying, paving the way for new discoveries and innovations in the field of materials science.

Delmic SPARC Spectral
Advanced CL Imaging Modes

Time-resolved Imaging
Investigate the dynamics of light emission and the behavior of excited states through time domains. Time-resolved imaging consists of two types: lifetime imaging and g(2) imaging, the latter of which is concerned with studying photon bunching and antibunching to accurately characterize single photon emitters, while lifetime imaging involves a pulsed electron beam to obtain decay-trace measurements associated with excited states of optoelectronic devices.

Angle-resolved Imaging
Study wavelength-dependent intensity spectra to understand the momentum and propagation direction of emitted or scattered light. The paraboloid mirror and staging mechanism of the SPARC Spectral permit collection of the full beam intensity profile, measuring nearly 2π steradian of the upper hemisphere of CL emission. Pairing angle-resolved imaging with polarizers or color filters are unique options available with the SPARC Spectral due to its flexible modularity.

Hyperspectral Imaging
Analyze CL emission over a complete, high resolution spectrum to gain information about various electronic and optic properties. The SPARC Spectral benefits from an automatic micropositioning system to help yield a three-dimensional data cube that contains the spatial electron beam position coordinates and associated wavelengths; the quantities of which can be represented in different ways to depict specific excitation positions or emission spatial differences.

RGB and Panchromatic Intensity Imaging
Visualize the spatial distribution of luminescence intensity with Red-Green-Blue and panchromatic CL intensity mapping, each of which measures the light intensity for every electron beam position. In RGB intensity mapping, each value is represented by a corresponding RGB color channel. Conversely, panchromatic intensity accounts for a broad range of wavelengths to map the intensities onto a grayscale image.

Polarization-filtered Imaging
Acquire the full polarization states of CL emission by way of a polarization analyzer to selectively filter light in specific directions of the electromagnetic fields. Polarization-filtered CL imaging is useful for gauging anisotropic properties of semiconductor materials such as the electronic structure, crystal orientation, light coherence, scattering, and birefringence. Both angle-resolved and hyperspectral imaging can be used for a more thorough material analysis.

Lens Scanning Energy Momentum Imaging
Explore the energy and momentum distribution of the light emitted by a sample struck by an electron beam. This imaging technique, referred to as E-k CL imaging due to the involvement of the wave vector, essentially combines angle-resolved imaging with hyperspectral imaging. This combination yields wavelength-resolved data and angular distributions pertaining to the energy and momentum of emitted light, respectively.
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Delmic SPARC SPECTRAL: TIME-RESOLVED IMAGING
LAB Cube: Lifetime And Antibunching Detection System
LAB Cube Overview
The LAB Cube represents a state-of-the-art instrument designed to facilitate the exploration of time-dependent phenomena in cathodoluminescence imaging. Through its fiber coupling module, the device interfaces with the SPARC Spectral and contains a suite of critical components, including an interferometer, beam splitter, neutral density/color filters, and two ultrafast single photon detectors.
By enabling the study of electron excitation and relaxation processes in tandem with optical and electronic properties of samples such as defects and band structures, the LAB Cube provides a valuable tool for researchers seeking to better understand the dynamics of materials. Its ability to capture short-lived electronic states and rapid carrier dynamics of semiconductors, quantum dots, and plasmonic nanoparticles further underscores its usefulness in a variety of contexts.
With the SPARC Spectral, g(2) imaging can be used with a constant or pulsed electron beam, whereas lifetime imaging of excited states is exclusive only to pulsed beams.

Second-order Autocorrelation Function: g(2) Imaging
In the field of quantum optics, the second-order autocorrelation function plays a pivotal role in describing the statistical behavior of photons emitted by a material. When it comes to cathodoluminescence imaging, this parameter takes on particular significance, as it governs the coherence and bunching or antibunching of photons.
By leveraging the appropriate tools and techniques, cathodoluminescence imaging can be utilized to precisely localize, identify, and characterize single emitters, providing researchers with valuable insights into the underlying physics of light-matter interactions at the nanoscale. As such, the second-order autocorrelation function is a crucial parameter in the field of cathodoluminescence imaging, offering a powerful means of probing the properties of materials and advancing our understanding of fundamental physical processes.
Lifetime Imaging
In cathodoluminescence, researchers probe the excited states of materials and gain insights into the complex interactions between electrons, light, and matter at the nanoscale. By employing lifetime imaging, researchers can measure the decay of luminescence over time, providing a detailed look at the dynamics of electron-beam-induced excitation and de-excitation processes.
A lifetime map of the sample can reveal a wealth of information about the fundamental physics of these interactions, shedding light on phenomena such as defects or impurities that may affect the length of excited states in semiconductor materials, radiative and non-radiative decay processes in plasmonic nanostructures, and charge carrier recombination in photovoltaic materials. By utilizing cathodoluminescence and lifetime imaging in their research, scientists can uncover key insights into the behavior of materials at the nanoscale, paving the way for new discoveries and innovations in a wide range of fields.