Terahertz real-time camera based on uncooled silicon-based antenna and resonant cavity coupled bolometer array
Dr François Simoens, CEA-Leti MINATEC, France
The development of Terahertz (THz) applications is slowed down by the availability of affordable, easy-to-use and highly-sensitive detectors. CEA-LETI took up this challenge by tailoring the mature Infrared (IR) bolometer technology for optimized THz sensing. The key feature of these detectors relies on the separation between electromagnetic absorption and the thermometer: for each pixel specific structures of antennas and a resonant quarter-wavelength cavity couple efficiently the THz radiation on a broadband range, while a central silicon microbridge bolometer resistance is read-out by a CMOS circuit providing high signal to noise ratio. 320x240 pixel arrays have been designed and manufactured: better than 30 pW power direct detection threshold per pixel has been demonstrated in the 2-4THz range. Such performance is expected on the whole THz range by proper tailoring of the antennas while keeping the technological stack unchanged.
This paper first reports the latest performance characterizations. Then imaging demonstrations are described, such as terahertz spectro-imaging techniques applied to concealed sugar pellets identification, real-time reflectance imaging of large surface of hidden objects and THz TDS beam 2D profiling. Then perspectives of camera integration for scientific and industrials applications are discussed.
Co-author: Jérôme Meilhan, CEA Leti-MINATEC
Integrated Photon Counting Technologies: CMOS and Beyond
Professor Edoardo Charbon, TU Delft, Netherlands
Photon counting has been used in many fields of science, medicine, and engineering for decades, contributing to important inventions, such as single-photon emission computed spectroscopy (SPECT), positron emission tomography (PET), fluorescence lifetime imaging microscopy (FLIM), and quantum cryptography. The evolution from single pixel to multi-pixel photon counters, and the implementation of CMOS sensors has accelerated the impact of this technology and expanded the field of applications.
Until recently, photomultiplier tubes have been the detector of choice for photon counting applications; the emergence of solid-state silicon photomultipliers and single-photon imaging has changed the status quo creating a true revolution and triggering an impressive series of innovations in high-energy physics, medical imaging and diagnostics, instrumentation, and consumer electronics.
In this talk, I will outline the advantages of solid-state photon counting in imaging applications and I will show how it is achieved in existing CMOS processes. I will discuss several technology directions in advanced, deep-submicron technologies and the emergence of new materials for extended spectra of detection and ultra-high speed of operation.
Professor David Miller, FRS, Stanford University, USA
Recently, motivated by potential use in short-distance optical interconnects, optoelectronic devices with single femtojoule operating energies have been demonstrated, making them comparable in energy to some current logic gates. Can optoelectronics continue to scale to even lower, attojoule energies? How could we make such devices? What nanophotonic concepts, such as nanoresonators or nanometallic field concentration, would they exploit? Could we integrate these with electronics for very low energy systems? As scaling in electronic devices becomes more difficult, would such optoelectronics even take over any of the logic functions? What new system performance might be possible?
Analog synthetic biology: from cells to electronics and electronics to cells
Professor Rahul Sarpeshkar, MIT, USA
Analog electronic circuits and circuits in cell biology are deeply similar: the equations that describe noisy electronic flow in sub-threshold transistors and the equations that describe noisy molecular flow in chemical reactions, both of which obey the laws of exponential thermodynamics, are astoundingly similar. Based on this similarity, we show how to map analog electronic circuit motifs to analog DNA-protein circuit motifs in cells. In addition, highly computationally intensive noisy DNA-protein and protein-protein networks can be rapidly simulated in mixed-signal supercomputing chips that naturally capture their noisiness, dynamics, and loading interactions at lightning-fast speeds. Such an approach may enable large-scale design and analysis in synthetic and systems biology. Experimental results from synthetic analog circuits in living cells with applications in biotechnology, medicine, bio sensing, and energy generation will be discussed.