All envisaged practical implementations of cryogenic processors, including quantum computers and classical processors based on single flux quantum (SFQ) signals, require massive data transfer from and to classical high performance computers (HPCs). Cryogenic computing has recently become a very hot topic, including superconducting quantum computers (QCs), and classical processors based on single flux quantum (SFQ) signals. All envisaged practical implementations of cryogenic processors require massive data transfer from and to classical HPCs. The project aCryComm aims to develop building blocks for cryogenic photonics interconnects and eventually enable this challenging data transfer. The long-term goal is the development of an open-access platform to integrate classical optical interfaces based on low-loss silicon photonics, plasmonics, and nano light sources together with superconducting photonic and electronic devices, including SFQ-based co-processors for HPCs and for QCs.
We discuss about a fully-staring THz video camera prototype intended for security screening. The camera utilizes so-called kinetic inductance bolometers to detect THz radiation in the bandwidth of 0.3-1 THz. The imaging distance is 2.5 m with the nominal field-of-view of 2 m × 1 m. The camera is equipped with a kilo-pixel detector array, intermediate-scale cryogenics operating at 6 K, and low-noise electronics to read out the whole detector array. Here, we focus on describing the wide field-of-view and close-looking optical system of the imager.
We present a fully-staring THz video camera prototype intended for security screening. The camera utilizes so-called kinetic inductance bolometers to detect THz radiation in the bandwidth of 0.3-1 THz. The imaging distance is 2.5 m with the field-of-view being 2 m × 1 m. The camera is equipped with a kilo-pixel detector array, large field-of-view optics, intermediate-scale cryogenics operating at 6 K, and low-noise electronics to read out the whole detector array. The imaging capabilities of the system are demonstrated through radiometric performance characterization and actual imaging experiments.
VTT’s 3 μm SOI platform with record low propagation loss (0.1 dB/cm for fundamental mode), as well as polarization insensitivity, offers a rich portfolio of efficient passive and active components. With a view to extend the component toolbox by monolithically integrating high-speed plasmonic modulators, we have developed an a-Si:H based waveguide escalator to take out light from highly confined thick-SOI passives to the top layer where active materials are monolithically integrated. Using the compact escalator, monolithic integration of various high-speed active components on the 3 μm SOI platform are proposed.
The state-of-the-art infrared (IR) photodetectors are either thermal detectors (bolometers) or quantum detectors (photovoltaic and photoconductive detectors). Compared to quantum IR photodetectors, IR bolometers are slower and less sensitive but in turn, they offer lower cost without need for cooling and exotic materials (e.g. HgCdTe). Phonon/photon engineered materials offer interesting routes for enhancing room-temperature IR bolometers. We have recently demonstrated experimentally a nano-thermoelectric bolometer for long-wave IR detection. The technology utilizes efficient thermoelectric transducers based on silicon nanomembranes, which have an enhanced thermoelectric figure of merit arising from the low thermal conductivity stemming from the nano-scale thickness. For the absorption of the IR radiation the nano-thermoelectric bolometer utilizes a nanomembrane based quarter-wave resistive absorber, which is also known as the Salisbury screen. The use of nanomembranes in both the thermoelectric transducer and the absorber results in a very small thermal mass, and thereby high speed for the detector. In this article, we present an analytical model for quarter-wave resistive absorbers (i.e. Salisbury screens). It can be applied both in radio frequency (RF) and optical applications. The results of the analytical model are compared with the ones obtained with the transfer-matrix method using the optical material data available in the literature. We present also a device model of the nano-thermoelectric IR detector and estimate the full performance of this technology.
VTT Technical Research Centre of Finland has developed two reader prototypes for immunodiagnostic tests. VTT has
also developed a one-step, homogeneous noncompetitive immunoassay for small analytes using recombinant antibodies
and morphine as the model analyte. VTT developed reader for lateral flow test. Lateral flow test is a strip, which has a sample area and a detection area. In the sample area there are antibodies attached to gold or fluorescence particles, which are captured into the detection area, if a sample has a desired analyte. The concentration of the measured sample is then calculated from the fluorescence
detection or color change. The second developed prototype reader is based on Time Resolved Fluorescence Resonance Energy Transfer
(TR-FRET). In this reader samples are put on microwell array. There are two fluorophores in each of the wells and
emission of both fluorophores is measured. The sample concentration is calculated from these emission signals. The
optimization of homogenous FRET assays for morphine was included to this project. The first results obtained with the
TR-FRET reader prototype show that the sensitivity of the current morphine test is clearly adequate.