scholarly journals Near Centimeter-scale FT-MIR Spectrometer based on NZIM Perfect Absorption using Inverted TanCirc Conformal Mapping Geometry

Author(s):  
Dwight W. Swett

Abstract A long sought objective of MEMS research within the oil & gas industry has been the realization of “FT-IR on a chip,” which could hold the potential to migrate laboratory grade chemical spectroscopy into downhole sensor suites. A fundamental obstacle to this research has been the cooling demands of conventional technologies which conflict with the miniaturized sensor volumes required in downhole logging systems and environmental conditions that routinely exceed 125 • C. Near centimeter scale spectroscopic devices are required by a majority of downhole sensor suites, which stands in stark contrast to multiple-decimeter size conventional devices. Here we report a near-centimeter scale FT-MIR ATR spectrometer compatible with downhole volumetric and temperature constraints. The spectrometer is based upon a high-temperature broadband mid-infrared metasurface detector/source combination derived from a geometric inversion of a set of conformal mapping contours. The metasurface elemental structure is derived from a geometric inversion of the canonical TanCirc conformal mapping contours and was found to exhibit a near zero index metamaterial (NZIM) behavior over a spectral range of interest for downhole chemical spectroscopy. The NZIM properties of the metasurface lead to an absorption phenomenon characterized by surface plasmon resonances which confine the absorption mechanism within the ultrathin (λ /300) metasurface plane and make the absorption properties of the microbolometer design relatively insensitive to the material properties of the remaining laminae. This unusual feature allows the metasurface to be integrated on a single VO 2 material thermometric layer and operated at elevated downhole temperatures despite corresponding to the VO2 metal-insulator-transition (MIT) region. Within this transition region however the VO2 layer exhibits a substantially beneficial property in that the VO 2 layer exhibits more than an order of magnitude enhancement in its ambient thermometric properties, leading to an uncooled microbolometer design with predicted maximum detectivity D * = 1.5 × 10 10 cm √ Hz/W and noise equivalent difference temperature NEDT of 1 mK at a modulation frequency of 500 Hz. A sub-millimeter scale thermal infrared source with intrinsic mid-infrared band-limited emission is formed from the same cellular geometric building block, enabling the spectrometer miniaturization. These performance parameters compare well with lower tier laboratory grade FT-MIR spectroscopic instruments and could represent a significant step in the effort towards deploying miniaturized high-temperature mid-infrared spectroscopy into oilfield downhole logging applications.

2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Xin Luo ◽  
Zi-Qiang Cheng ◽  
Xiang Zhai ◽  
Zhi-Min Liu ◽  
Si-Qi Li ◽  
...  

Abstract A suspended monolayer graphene has only about 2.3% absorption rate in visible and infrared band, which limits its optoelectronic applications. To significantly increase graphene’s absorption efficiency, a tunable dual-band and polarization-insensitive coherent perfect absorber (CPA) is proposed in the mid-infrared regime, which contains the silicon array coupled in double-layers graphene waveguide. Based on the FDTD methods, dual-band perfect absorption peaks are achieved in 9611 nm and 9924 nm, respectively. Moreover, due to its center symmetric feature, the proposed absorber also demonstrates polarization-insensitive. Meanwhile, the coherent absorption peaks can be all-optically modulated by altering the relative phase between two reverse incident lights. Furthermore, by manipulating the Fermi energies of two graphene layers, two coherent absorption peaks can move over a wide spectrum range, and our designed CPA can also be changed from dual-band CPA to narrowband CPA. Thus, our results can find some potential applications in the field of developing nanophotonic devices with excellent performance working at the mid-infrared regime.


Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1485
Author(s):  
Wei Wang ◽  
Ruikang Zhao ◽  
Shilong Chang ◽  
Jing Li ◽  
Yan Shi ◽  
...  

In this paper, one spin-selected vortex metalens composed of silicon nanobricks is designed and numerically investigated at the mid-infrared band, which can produce vortex beams with different topological charges and achieve different spin lights simultaneously. Another type of spin-independent vortex metalens is also designed, which can focus the vortex beams with the same topological charge at the same position for different spin lights, respectively. Both of the two vortex metalenses can achieve high-efficiency focusing for different spin lights. In addition, the spin-to-orbital angular momentum conversion through the vortex metalens is also discussed in detail. Our work facilitates the establishment of high-efficiency spin-related integrated devices, which is significant for the development of vortex optics and spin optics.


Author(s):  
G. Friedrichs ◽  
H.Gg. Wagner

The technique of time resolved frequency modulation (FM) spectroscopy has been shown to provide a very sensitive means to detect small radicals behind shock waves. Features of high temperature FM spectroscopy behind shock waves will be discussed and a general signal conversion procedure to carry out quantitative concentration measurements will be presented.Using a high modulation frequency, a high modulation index and high total optical power, singlet methylene radicals (α


2021 ◽  
Vol 119 (14) ◽  
pp. 141109
Author(s):  
Yun Meng ◽  
Dan Li ◽  
Chong Zhang ◽  
Yang Wang ◽  
Robert E. Simpson ◽  
...  

2021 ◽  
Vol 2125 (1) ◽  
pp. 012006
Author(s):  
Nan Wu ◽  
Chengpo Mu ◽  
Yang He ◽  
Huan Liu ◽  
Taiye Liu

Abstract In order to study the infrared radiation (IR) characteristics of rocket engine plume in the mid infrared band, a calculation model for IR transfer of rocket engine plume was built. The flow field data are calculated by software FLUENT. Based on HITRAN database, the IR characteristic parameters are calculated after spectral line correction. The Line of Sight (LoS) is used to solve the radiation characteristics in the plume flow field, and the IR characteristics distribution of the plume in the mid infrared band is obtained, which agree well with the results from open literature. The method has the advantages of simple model, less parameters and fast calculation speed in this paper.


Crystals ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 354 ◽  
Author(s):  
Yindi Wang ◽  
Hongxia Liu ◽  
Shulong Wang ◽  
Ming Cai ◽  
Lan Ma

The excellent transmission characteristics of graphene surface plasmon polaritons in mid-infrared band were analyzed and verified effectively through theoretical derivation and soft simulation in this paper. Meanwhile, a sandwich waveguide structure of dielectric–graphene–substrate–dielectric based on graphene surface plasmon polaritons (SPPs) was presented. Simulation results indicate that graphene SPPs show unique properties in the mid-infrared region including ultra-compact mode confinement and dynamic tunability, which allow these SPPs to overcome the defects of metal SPPs and traditional silicon-based optoelectronic devices. Thus, they can be used to manufacture subwavelength devices. The work in this paper lays a theoretical foundation for the application of graphene SPPs in the mid-infrared region.


Sensors ◽  
2018 ◽  
Vol 19 (1) ◽  
pp. 89 ◽  
Author(s):  
Ming Cai ◽  
Shulong Wang ◽  
Bo Gao ◽  
Yindi Wang ◽  
Tao Han ◽  
...  

In this paper, a new electro-optical switch modulator based on the surface plasmon polaritons of graphene is proposed. An air–graphene-substrate–dielectric structure is adopted in the modulator. In this structure, the graphene is considered as a film of metal whose thickness tends to be infinitesimal. By changing the external voltage, the boundary conditions can be changed to decide whether the surface plasmon polariton waves can be excited in mid-infrared band. Because of this effect, the structure can be used as an electro–optical switch modulator, whose modulation depth is about 100% in theory. Finally, the 3 dB bandwidth (~34 GHz) and the energy loss (36.47 fJ/bit) of the electro–optical switch modulator are given, whose low energy loss is very suitable for engineering applications.


2018 ◽  
Vol 32 (03) ◽  
pp. 1850029 ◽  
Author(s):  
Zong-De Ju ◽  
Guo-Qing Xu ◽  
Zhi-Hua Wei ◽  
Jing Li ◽  
Qian Zhao ◽  
...  

A single-patterned five-band terahertz metamaterial absorber based on simple metal–dielectric–metal sandwich structure is investigated and demonstrated. The numerical simulations reveal the different dependence of the absorption ability on the incident polarization angle, dielectric layer, and structural dimensions of the single pattern. The extracted electric field distribution indicates that the five-band near-perfect absorption performance (average over 98%) mainly originates from the combination of LC, dipole, quadrupole, and high-order resonance. The researches on magnetic field and power loss density distributions further reveal the absorption mechanism. Moreover, additional resonance mode can be excited to form a six-band high-performance absorber only by adjusting some geometric dimensions of the single pattern with multiple resonance modes. The simple method provides us a very good idea to implement a super multi-band absorber. The proposed absorbers here can be applied in massive related fields, such as metamaterial sensors, thermal radiation, and imaging system.


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