Long-distance heat transfer between molecular systems through a hybrid plasmonic-photonic nanoresonator

We theoretically study a hybrid plasmonic-photonic cavity setup that can be used to induce and control long-distance heat transfer between molecular systems through optomechanical interactions. The structure we propose consists of two separated plasmonic nanoantennas coupled to a dielectric cavity. The hybrid modes of this resonator can combine the large optomechanical coupling of the sub-wavelength plasmonic modes with the large quality factor and delocalized character of the cavity mode that extends over a large distance (∼µm). We show that this can lead to effective long-range heat transport between molecular vibrations that can be actively controlled through an external driving laserThis work has been funded by the European Research Council through grant ERC-2016-StG-714870 and by the Spanish Ministry for Science, Innovation, and Universities—Agencia Estatal de Investigación through Grant Nos. RTI2018-099737-B-I00, PCI2018-093145 (through the QuantERA program of the European Commission), and MDM-2014-0377 (through the María de Maeztu program for Units of Excellence in R&D), as well as through a Ramón y Cajal grant (J F) and support from the Iranian Ministry of Science, Research and Technology (SMA

Optomechanical heat transfer between molecules in a nanoplasmonic cavity

We explore whether localized surface plasmon polariton modes can transfer heat between molecules placed in the hot spot of a nanoplasmonic cavity through optomechanical interaction with the molecular vibrations. We demonstrate that external driving of the plasmon resonance indeed induces an effective molecule-molecule interaction corresponding to a heat transfer mechanism that can even be more effective in cooling the hotter molecule than its heating due to the vibrational pumping by the plasmon. This mechanism allows us to actively control the rate of heat flow between molecules through the intensity and frequency of the driving laserThis work has been funded by the European Research Council (ERC-2016-STG-714870) and the Spanish MINECO under Contract No. MAT2014-53432-C5-5-R and the “María de Maeztu” programme for Units of Excellence in R&D (MDM-2014-0377), as well as through a Ramón y Cajal grant (JF) and support from the Iranian Ministry of Science, Research and Technology (SMA

Investigation in to Properties of Polyurethane Closed Cell by High Loading of SiO 2 Nanoparticles

Abstract In this research the composition of polyurethane closed cell (PUCC

Gamma radiation dosimetry using transmission and reflection spectroscopy of KCl

In this article we have shown that it is possible to use transmission, absorption and reflection spectroscopic data of KClxBr1-x single crystals for the TL (Thermo Luminescence) dosimetry purposes in the spectral range of 250-750 nm. The effects of gamma radiation on KClxBr1-x single crystals were investigated by radiating the samples with a 60Co source and studying the reflection and absorption spectra. Six doses of gamma radiation of 145, 300, 450, 600, 750 and 900 Gy were examined. The absorption peak height in the spectral region of 560-580 nm is in a direct relationship with the gamma radiation doses up to about 800 Gy, in which saturation starts to occur. The intensities of the color centers in mixed crystals are different by their combination ratios of the components contents. According to the reflection and transmission data, the absorption spectra can be calculated and a calibration curve sketched

Raman Scattering and Electrical Properties of TGS:PCo (9%) Crystal as Ambient Temperature IR Detector

We developed and adequately characterized the triglycine sulfate family crystals doped with specific molar percent of cobalt phosphate, TGS:PCo (9%). The crystals were grown by slow evaporation technique and the growth rates of different crystallographic planes are rather faster in comparison with the plane growth rates of pure TGS crystals. The introduction of $Co^{2+}$ ion as an active optical element to the structure of TGS crystal leads to optimization of some parameters such as optical quality, stability at ambient condition, Curie temperature, stronger Raman peaks, etc. Three new peaks at 460, 620 and 1368 $cm^{-1}$ were observed in the dispersive back scattering Raman spectra of the grown TGS:PCo (9%) crystal in comparison with the pure triglycine sulfate crystal

The behavior of a system with one atom confined in a Fabry-Perot optical cavity with a nonlinear mirror

In this paper the treatment of a three-level atom which is confined in a Fabry-Perot optical cavity with a nonlinear mirror is investigated. Despite the nonlinear effects we show that this system operates in two different regimes. In one regime the system shows conventional laser properties which is approximated by a semiclassical laser theory and in the other one the system displays new quantum properties which is approximated by an effective two-level atom. For validity of the behavior of the system in two different regimes computer simulations are implemented

Determination of Nonlinear Optical Properties of MgO Nanoparticles Doped in Poly (Ether) Urethane

The third-order optical nonlinearities of poly (ether) urethane open cell (PEUOC)/MgO nanocomposites, dissolved in dimethylformamide are characterized by Z-scan technique with CW Nd:YAG laser at its second harmonic frequency of 532 nm with TEM00 Gaussian profile. The synthesized samples are also characterized by optical microscopy and scanning electron microscopy imaging. The nonlinear refractive indices and nonlinear absorption coefficients of the synthesized samples are obtained in the order of $10^{-8} cm^{2}//W$ with negative sign and $10^{-5} cm//W$, respectively. The origin of optical nonlinearity in this case may be attributed due to the presence of strong saturable absorption effect. All the results suggest that the nonlinear coefficients of the synthesized samples can be controlled by nanoparticles content into PEUOC. Furthermore, the results show that PEUOC/MgO may be promising candidate for the application to optical limiting in the visible region

Optical and Physical Properties of SiO2 Nanoparticles and Tetra Ortho Silicate

In this article optical and physical property of the composition of polyurethane open cell (PUOC) with two different concentrations of SiO2 nanoparticles (1 and 2wt. %) will be reported. Tetra ortho silicate (TEOS) as an organic agent with different concentrations trations (0.05, 0.1, 0.15 and 0.2 Vol./Vol.) was added to polyurethane composition. Optical microscopy imaging, watering uptake, FTIR and Raman spectroscopy of the synthesized samples were measured. The cell size of samples by adding SiO2 NPs and TEOS was decreased. The PUOC/1wt. % SiO2 was recognized as a best specimen for absorbing water. By focusing on the recorded Raman spectra, it is revealed that PUOC/1wt. % SiO2 and PUOC/200µl TEOS have more covalent bonds than others. The degree of phase separation, DPS, and the hydrogen bonding index, R, in samples were evaluated in terms of their FTIR spectroscopy data. Two samples, PUOC/1wt. % SiO2 and PUOC/800µl TEOS, have the highest R and DPS factors among the synthesized samples. By adding SiO2 NPs and TEOS into to PUOC, the apparent density of foams was increased. This is similar to the behavior of real density in SiO2 NPs into PUOC but by adding TEOS into PUOC, the real density of samples were decreased. The total porosity, open porosity and closed porosity of the synthesized samples were calculated. By adding SiO2 NPs and TEOS into PUOC, the open porosity of samples was increased

Dispersive Micro Raman Backscattering Spectroscopy Investigation of Arc Discharge Synthesized CNTs Doped by Boron and Nitrogen

Raman scattering studies reveal the remarkable structure and the unusual electronic and phonon properties of carbon nanotubes. In this study, we directly produced boron, B, and nitrogen doped carbon nanotubes by using DC-arc discharge method which normally can be employed for producing carbon nanotubes. We performed experiments without using catalysts and in the presence of Ar gas for producing boron doped carbon nanotubes. At the second and third stages and in the presence of $Al_{2}O_{3}$ and MgO nanopowders as catalysts and nitrogen gas were used for producing nitrogen doped carbon nanotubes. In general, our investigation revealed that some major changes caused by B and N dopants can be observed in the related recorded Raman spectra

Raman Spectra and Structural Data of the Nanocrystalline KTP (KTiOPO 4

Nanocrystalline KTP powders are synthesized using a modified Pechini method. The structural and lattice modes of the products are investigated via X-ray diffraction, micro Raman backscattering spectroscopy, UV/vis/NIR and FT-IR transmission spectroscopy. The Debye-Scherrer formula is used to confirm the grain sizes estimated by the scanning electron microscopy slides