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1

Diminutive left-handed plasmonic nanoantenna-lens system in optical realm: ultraviolet emission and flat lens application

Rajput Monika, Dabas Bhawana, Saini Than Singh, Mehta Neeru

Optica Applicata

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2019

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Vol. 49, nr 4

679--692

EN

In present paper, a tunable left-handed plasmonic nanoantenna is designed to attain ultraviolet emission through a second harmonic generation with a phase harmonic condition. For the devised structure, the dispersion properties and negative values of the magnetic permeability and the electric permittivity show that the designed structure is left-handed for the primary wave (red light) and right-handed for the second harmonic wave (ultraviolet light). The 3D finite-difference time-domain method is employed to reveal its nonpareil skills (i.e. immense left-handed transmission efficiency and far-field spectrum exhibiting directionality). Attained results by numerical calculation for the second harmonic generation are accomplished with finite-difference time-domain analysis. The impact of physical parameters on transmission and dispersion characteristics is also scrutinized. Furthermore, flat lens application for a red light region with a centered wavelength at λ = 650 nm from the guileless design of LHM with no aberration is triumphed. Ultimately, a multifunction left-handed material is designed revealing tremendous potential to amass and abridge future applications in one architecture.

2

Studies on the growth and characterization of L-cysteine hydrogen fluoride single crystal

Mohammed Azeezaa Varsha, Sagadevan Suresh

Materials Science Poland

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2019

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Vol. 37, No. 3

304--309

EN

L-cysteine hydrogen fluoride (LCHF) single crystals were grown from aqueous solution. Single crystal X-ray diffraction, FT-IR, UV-Vis-NIR, and TG-DTA were used to test the grown crystals. The specimen dielectric and mechanical behaviors were also studied. Powder X-ray diffraction of the grown crystal was recorded and indexed. The optical properties of the LCHF crystal were determined using UV-Vis spectroscopy. It was found that the optical band gap of LCHF was 4.8 eV. The crystal functional groups were identified using FT-IR. Second harmonic generation (SHG) efficiency of the LCHF was three times higher than that of KDP. The dielectric constant, dielectric loss and AC conductivity were measured at different frequencies and temperatures.

3

Growth, characterization and optical properties of potassium iodide (KI) doped potassium hydrogen phthalate (KHP) single crystals for optoelectronic applications

Raju R. K., Beena P., Jayanna H. S.

Materials Science Poland

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2019

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Vol. 37, No. 3

510--516

EN

Potassium iodide (KI) doped potassium hydrogen phthalate (KHP) single crystals were grown by slow evaporation technique using millipore water as a solvent. The grown single crystals were analyzed by powder X-ray diffraction and the analysis confirmed that KI-doped KHP crystallizes in orthorhombic system with space group Pca21. The functional groups were identified by FT-IR technique which showed slight shift in vibrational frequencies, indicating inclusion of dopant into the crystal lattice. The UV-Vis spectral studies revealed the optical transparency of the doped crystals in the entire visible region. The optical band gap values were estimated from Tauc plots. Kurtz-Perry powder test was employed for second harmonic generation efficiency studies of the grown crystals.

4

Long-term Absolute Wavelength Stability of Acetylene-stabilized Reference Laser at 1533 nm

Kossek T., Czułek D., Koba M.

Journal of Telecommunications and Information Technology

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2016

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nr 4

88--93

EN

The second harmonic generation process in Periodically Poled Lithium Niobate (PPLN) has been applied in order to measure frequency of reference laser locked to acetylene absorption peak 12C2H2 (P13) (1533 nm) against optical frequency synthesizer. The measurement results have been compared to the results obtained using different techniques for the same reference laser during the past 10 years in other laboratories.

5

Nowe zasady pomiaru drugiej harmonicznej światła (SHG) w materiałach o zróżnicowanej wartości podatności nieliniowooptycznej

Wojciechowski A.

Elektronika : konstrukcje, technologie, zastosowania

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2016

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Vol. 57, nr 11

71--74

PL

Opracowano nowe podejście do pomiaru zjawiska drugiej harmonicznej światła (SHG) polegające na rejestracji kinetyki czasowego opóźnienia maksimum przebiegu sygnału SHG względem maksimum sygnału fali fundamentalnej (FUN) oraz pomiar kinetyki SHG. Z analizy literaturowej wynika, że dotychczas najczęściej prowadzono pomiar efektywności przetwarzania SHG jako stosunek maksimum natężenia SHG do maksimum fali padającej. Nowe podejście dostarcza dodatkowych informacji o kinetyce obsadzenia poziomów pułapkowych w obszarach częściowo nieuporządkowanych badanych materiałów, które generują dodatkowy sygnał SHG. Istotnym jest to ze metoda ta może być stosowana do materiałów posiadających duży (do 5 rzędów) rozrzut efektywności SHG. Ustalono podstawowe parametry techniczne wpływające na efektywność drugiej harmonicznej światła. Ustalono że przy tej samej gęstości mocy promieniowania istnieje prawie odwrotnie proporcjonalna relacja pomiędzy czasem opóźnienia i efektywnością drugiej harmonicznej. Oprócz tego zbadano wpływ innych czynników na dokładność pomiarów. Podstawy teoretyczne są oparte na analizie hiperpolaryzowalności wielu materiałów. Wśród nich nanokompozyty, monokryształy, nanoproszki i inne.

EN

We developed a new approach to measuring the phenomenon of second harmonic of the light (SHG) involving the registration of the kinetics of the time delay of the maximum waveform SHG terms of maximum wave signal fundamental (FUN) and the measurement of the kinetics of SHG. The analysis of the literature shows that until now the mostly introduced measurement processing efficiency as the ratio of the maximum of SHG to the maximum of the incident wave. The new approach provides additional information about the kinetics of filling of the traps levels in areas partially disordered for the tested materials, which generate additional SHG signal. It is important that this method can be used for materials with large (up to 5 rows) dispersion of SHG efficiency. It was found that for the same power density of the radiation are inversely proportional relationship between the delay time and efficiency of the second harmonic. In addition, were examined the effect of other factors on the accuracy of the measurements. Theoretical foundations are based on the analysis of hyperpolarizabilities of many materials. Among these nanocomposites, single crystals, nanopowders and other.

6

Enhanced resonant second harmonic generation in plasma based on density transition

Kant N., Thakur V.

Nukleonika

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2015

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Vol. 60, No. 2

355--360

EN

Resonant second harmonic generation of a relativistic self-focusing laser in plasma with density ramp profile has been investigated. A high intense Gaussian laser beam generates resonant second harmonic beam in plasma with density ramp profile. The second harmonic undergoes periodic focusing in the plasma channel created by the fundamental wave. The normalized second harmonic amplitude varies periodically with distance and attains maximum value in the focal region. Enhancement in the second harmonic amplitude on account of relativistic self-focusing of laser based on plasma density transition is seen. Plasma density ramp plays an important role to make self-focusing stronger which leads to enhance the second harmonic generation in plasma.

7

Simulation of the thermo-optic coupling effect in mid-infrared second harmonic generation of ZnGeP2 crystal

Zhang W., Gao Y., Huang J., Zhang G., Andreev Y. M., Grechin S. G., Lanskii G. V.

Materials Science Poland

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2015

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Vol. 33, No. 2

391--396

EN

The thermo-optic coupling process of second harmonic generation was numerically simulated in ZnGeP2 crystals pumped by a pulsed CO2 laser at the wavelength of 9.6 mu m, under the strong and weak cooling conditions. The conversion efficiencies, temperature distributions were calculated during the evolution of the thermo-optic coupling. The results showed that the thermo-optic coupling was weak in the strong cooling condition, which nearly did not disturb the conversion processes and temperature distribution, while in the weak cooling case, the temperature distribution showed a great influence on the conversion efficiency and light intensity. Finally, it was found that compensation of the phase mismatch induced by the thermal effect can well recover the conversion efficiency.

8

Zjawisko generowania fal harmonicznych oraz jego wykorzystanie praktyczne ze szczególnym uwzględnieniem współczesnej ultrasonografii

Jeka S., Sokólska E., Dura M., Żuchowski P.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2011

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Vol. 17, nr 2

140-143

PL

Od wielu lat z postępem w dziedzinie fizyki związany jest postęp w naukach przyrodniczych. Jednym ze zjawisk, które odgrywa coraz większą rolę w naukach przyrodniczych, jest zjawisko generacji drugiej harmonicznej w ośrodkach anizotropowych. Możliwość uzyskania fali o podwojonej częstotliwości w stosunku do fali podstawowej pozwoliło na prowadzenie badań, wcześniej trudnych bądź niemożliwych do przeprowadzenia. Dzięki wyższej jakości obrazu badania ultrasonograficzne stały się bardziej czułe i są powszechnie wykorzystywane, m.in. w kardiologii, radiologii, chirurgii, reumatologii czy diagnostyce onkologicznej. Ultrasonografia staje się niezwykle cenioną metodą obrazowania obok rezonansu magnetycznego czy tomografii komputerowej. Ze względu na jej dostępność wiązane są z nią duże nadzieje na przyszłość.

EN

The progress in physics results in life sciences advancement. One of the phenomena, which plays more and more important role in life sciences, is the second harmonic generation in anisotropic materials. The possibility of achieving the wave, characterized by double frequency – with relation to the initial wave, allowed to conduct examinations, which were previously very difficult or impossible to perform. Thanks to higher quality of image, ultrasound examination has become more sensitive and is widely used, even in cardiology, radiology, surgery, rheumatology and oncology diagnostics. Ultrasonography with the use of tissue harmonic imaging is very valued method, so as magnetic resonance imaging or CT scan and due to its availability, high expectations are associated with it for the future.

9

Blue 473-nm solid state diode pumped Nd:YAG/BiBO microchip laser

Antończak A. J., Sotor J. Z., Matysiak M., Abramski K. M.

Opto-Electronics Review

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2010

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Vol. 18, No. 1

71-74

EN

In this paper we present a design of a compact, low power diode-pumped CW Nd:YAG laser operating at 946 nm with intracavity blue light generation at 473 nm for battery operated applications. The nonlinear crystal used in the experiment is a BiBO crystal cut for phase-matching type I. Using 0.8 W of pumping power, 20-mW stabile output power of blue light was achieved. The second harmonic generation conversion efficiency was 2.5%.

10

New Ferrocenylpyridinium Salts with Bulk Second-Order Nonlinear Optical Properties

Plażuk D., Zakrzewski J., Nakatani K.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 12

2105-2111

EN

Protonation of (E)-1-ferrocenyl-2-(pyridin-4-yl)-ethylene with (+)-camphor-10-sulfonic and picric acid afforded salts displaying high second harmonic generation (SHG) efficiencies (70 and 10 × urea, respectively). Powder X-ray diffraction study confirmed crystallization of these salts in a noncentrosymmetric space group (P2). The electronic structure of the cationic part of the salts was studied by the DFT method.

11

Układy kontroli i aktywnej stabilizacji częstotliwości jednoczęstotliwościowych mikrolaserów ciała stałego

Antończak A. J., Sotor J. Z., Abramski K. M.

Elektronika : konstrukcje, technologie, zastosowania

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2008

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Vol. 49, nr 11

104-108

PL

W pracy zaprezentowano praktyczną realizację jednoczęstotliwościowego mikrolasera Nd:YAG/KTP z dwójłomnym filtrem Lyota. Zaprezentowano nowy oryginalny układ stabilizacji częstotliwości z wykorzystaniem światłowodowej siatki Bragga jako znacznika częstotliwości. Określono długoterminową stałość częstotliwości badanych jako: 6-10⁻⁷.

EN

The paper deals with the basic set-up of single-frequency microchip laser - so called Lyot filter configuration. Some results obtained for neodymium microchip lasers are presented. New techniques of frequency stabilization by external fiber Bragg grating is presented. Long term frequency stability of the lasers at the level of 6-10⁻⁷ was obtained.

12

A New Chiral 4-[(E)-2-Ferrocenylvinyl]-1-methylpyridinium Iodide Exhibiting Bulk Second-Order Nonlinear Optical Properties

Janowska I., Zakrzewski J., Palusiak M., Nakatani K.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 5-6

1063-1070

EN

Two new chiral 4-[(E)-2-ferrocenylvinyl]-1-methylpyridinium iodides, having in the 2-position of the ferrocenyl group (R)-1-N,N-dimethylaminoethyl and (S)-2-methoxymethylpyrrolidin- 1-yl substituents were synthesized. The latter compound showed weak second harmonic generation efficiency (0.5 x urea) at 1907 m. The molecular structure and crystal packing of this compound were determined by single-crystal X-ray diffraction and are discussed in relation to its nonlinear optical properties.

13

Vibrational Spectra, Phase Transition and Nonlinear Optical Properties of Anilinium Perchlorate Molecular-Ionic Solid

Marchewka M., Debrus S., Drozd M., Baran J., Barnes A. J., Xue D., Ratajczak H.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 11

1625-1636

EN

Crystals of anilinium perchlorate, C6H5NH ClO 3 4 + , were obtained by slow evaporation of an aqueous solution at room temperature. Powder Kurtz-Perry measurements were performed for the title material. The efficiency of second harmonic generation was estimated relative to KDP: d = 0.21dKDP. Room temperature powder infrared and Raman measurements for the title solid and its deuterated analogue were carried out. The vibrational spectra in the regions of the internal vibrations of the ions corroborate the X-ray data (reported by Paixao et al. [1]). Differential scanning measurements performed on the powder sample indicate a first order phase transition at about 220 K.Apossible mechanism of the phase transition is suggested in relation to disorder of the hydrogen atoms on nitrogen atoms (reported in [1]). The role of the aniline molecule in the second harmonic generation is discussed.

14

Predicting optical properties of potassium hydrogen bis-trichloroacetate crystal

Xue D., Ratajczak H.

Bulletin of the Polish Academy of Sciences. Chemistry

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2003

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Vol. 51, No. 2

71-75

EN

The second order nonlinear optical coefficient dsg of potassium hydrogen bis-trichloroacetate molecular crystal is theoretically predicted by the chemical bond method, which shows that optical responses of this crystal originate from the C-C1 bonds. The predicted value of d(36) is in agreement with the experimental observation.

15

Hyperpolarizalities of pyridine derivatives and their protonated species: ab initio studies

Latajka Z., Gajewski G., Ratajczak H., Venturini J.

Bulletin of the Polish Academy of Sciences. Chemistry

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2003

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Vol. 51, No. 1

1-4

EN

The first hyperpolarizability values of pyridine derivatives and their proto-nated species have been calculated using ab intio (STO-3G) method. The effect of proto-nation on these values is discussed.

16

Some new aspect of the plane wave second harmonics generation in elastic bodies

Rushchitsky J.

Vibrations in Physical Systems

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2002

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Vol. 20

252--253

17

Second harmonic generation properties of potassium hydrogen bis-trichloroacetate crystal

Ratajczak H., Baran J., Debrus S.

Bulletin of the Polish Academy of Sciences. Chemistry

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2001

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Vol. 49, No. 4

261-264

EN

The SHG property was determined for the powder sample of potassium hydrogen bis-trichloroacetate crystal using the Kurtz-Perry method. SHG efficiency relative to KDP appears to be 0.57.

18

Second harmonic generation properties of [CH3NH3]5Bi2Br11 ferroelectric crystal

Ratajczak H., Debrus S., Jakubas R., Baran J.

Bulletin of the Polish Academy of Sciences. Chemistry

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2000

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Vol. 48, No. 3

193-194

EN

The SHG properties were determined for the powder samples of the [ChaNH3](5)Bi(2) Br(11)compound using the Kurtz-Perry method. SHG efficiency relative to KDP appears to be 0.4.