Integrated all-optical logic discriminators based on plasmonic bandgap engineering

Optical computing uses photons as information carriers, opening up the possibility for ultrahigh-speed and ultrawide-band information processing. Integrated all-optical logic devices are indispensible core components of optical computing systems. However, up to now, little experimental progress has been made in nanoscale all-optical logic discriminators, which have the function of discriminating and encoding incident light signals according to wavelength. Here, we report a strategy to realize a nanoscale all-optical logic discriminator based on plasmonic bandgap engineering in a planar plasmonic microstructure. Light signals falling within different operating wavelength ranges are differentiated and endowed with different logic state encodings. Compared with values previously reported, the operating bandwidth is enlarged by one order of magnitude. Also the SPP light source is integrated with the logic device while retaining its ultracompact size. This opens up a way to construct on-chip all-optical information processors and artificial intelligence systems.Comment: 4 figures 201

Ultrawide-band Unidirectional Surface Plasmon Polariton Launchers

Plasmonic devices and circuits, bridging the gap between integrated photonic and microelectronic technology, are promising candidates to realize on-chip ultrawide-band and ultrahigh-speed information processing. Unfortunately, the wideband surface plasmon source, one of the most important core components of integrated plasmonic circuits, is still unavailable up to now. This has seriously restricted the practical applications of plasmonic circuits. Here, we report an ultrawide-band unidirectional surface plasmon polariton launcher with high launching efficiency ratio and large extinction ratio, realized by combining plasmonic bandgap engineering and linear interference effect. This device offers excellent performances over an ultrabroad wavelength range from 690 to 900 nm, together with a high average launching efficiency ratio of 1.25, large average extinction ratio of 30 dB, and ultracompact lateral dimension of less than 4 um. Compared with previous reports, the operating bandwidth is enlarged 210 folds, while the largest launching efficiency ratio, largest extinction ratio, and small feature size are maintained simultaneously. This provides a strategy for constructing on-chip surface plasmon source, and also paving the way for the study of integrated plasmonic circuits.Comment: 4 figure

Hybrid Thermal-Chemical Enhanced Oil Recovery Methods:An Experimental Study for Tight Reservoirs

It is essential to have an adequate understanding of the fluid-structure in a porous medium since this gives direct information about the processes necessary to extract the liquid and the likely yield. The concept of symmetry is one of the petroleum engineering issues that has been used to provide an analytical analysis for modeling fluid dynamics through porous media, which can be beneficial to validate the experimental field data. Tight reservoirs regarding their unique reservoir characterization have always been considered as a challenging issue in the petroleum industries. In this paper, different injectivity scenarios which included chemical and thermal methods were taken into consideration to compare the efficiency of each method on the oil recovery enhancement. According to the results of this experiment, the recovery factor for foams and brine injection is about 80%, while it is relatively 66% and 58% for brine-carbon dioxide and brine-nitrogen, respectively. Consequently, foam injection after water flooding would be an effective method to produce more oil volumes in tight reservoirs. Moreover, KCl regarding its more considerable wettability changes has provided more oil production rather than other scenarios

A Circularly Polarized HTS Microstrip Antenna Array with Controllable Cryostat

A high-temperature superconductor (HTS) microstrip antenna array with right-hand circular polarization is proposed for space communications. The proposed HTS antenna array can achieve high efficiency, which is able to reduce the antenna’s loss. The array consists of 16 antenna elements being fed by a T-network. A pair of symmetric meander slots is used in each antenna element to broaden the input matching bandwidth. A controllable cryostat is used as the refrigeration for HTS. The experiment shows that the gain of the proposed HTS antenna is 8.39 dB, whose 10 dB return loss bandwidth is 2.2% ranging from 5.75 GHz to 5.87 GHz. In comparison with a traditional conductor antenna array having the same configuration, the proposed array has an 8.1 dB improvement in the gain and a 69.2% enhancement in the radiation efficiency