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1550 nm

Chao Tian, Ting Feng, Cheng Wang, Shengchun Liu, Qian Cheng, David E Oliver, Xueding Wang, Guan Xu
Most current photoacoustic imaging (PAI) systems employ piezoelectric transducers to receive photoacoustic signals, which requires coupling medium to facilitate photoacoustic wave propagation and are not favored in many applications. Here, we report an all-optical non-contact PAI system based on a commercial heterodyne interferometer working at 1550 nm. The interferometer remotely detects ultrasound-induced surface vibration and does not involve any physical contact with the sample. The theoretically predicated and experimentally measured noise equivalent detection limits of the optical sensor are about 4...
December 1, 2016: IEEE Sensors Journal
Sandra Dias, Kishan Kumawat, Shinjini Biswas, Salaru Babu Krupanidhi
Cu2SnS3 (CTS) quantum dots were synthesized by solvothermal technique with poly(vinylpyrrolidone) (PVP) as a surfactant. The structural and optical properties were studied using X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and UV-vis spectroscopy. The electronic band gap was measured using cyclic voltammetry. The infrared photoresponse of the CTS quantum dots-incorporated device was measured under different illumination intensities of the infrared lamp, 1550 and 1064 nm lasers...
February 20, 2017: Inorganic Chemistry
Jiaxiong Li, Jiangbing Du, Lin Ma, Ming-Jun Li, Ke Xu, Zuyuan He
We experimentally demonstrate and investigate, for first time to our best knowledge, a second-order few-mode Raman amplifier for low noise distributed fiber amplification. The 1455 and 1360 nm pumps are both injected into the few-mode fiber (FMF) in the forms of two degenerate LP<sub>11</sub> modes in the backward direction. Within the band from 1542 to 1558 nm, maximum on-off gains of 4 dB are achieved for both LP<sub>01</sub> and LP<sub>11</sub> modes, and the differential modal gain (DMG) is less than 0...
January 23, 2017: Optics Express
Shamsul Arafin, Arda Simsek, Seong-Kyun Kim, Sarvagya Dwivedi, Wei Liang, Danny Eliyahu, Jonathan Klamkin, Andrey Matsko, Leif Johansson, Lute Maleki, Mark Rodwell, Larry Coldren
An integrated heterodyne optical phase-locked loop was designed and demonstrated with an indium phosphide based photonic integrated circuit and commercial off-the-shelf electronic components. As an input reference, a stable microresonator-based optical frequency comb with a 50-dB span of 25 nm (~3 THz) around 1550 nm, having a spacing of ~26 GHz, was used. A widely-tunable on-chip sampled-grating distributed-Bragg-reflector laser is offset locked across multiple comb lines. An arbitrary frequency synthesis between the comb lines is demonstrated by tuning the RF offset source, and better than 100Hz tuning resolution with ± 5 Hz accuracy is obtained...
January 23, 2017: Optics Express
Morgan Mathez, Peter John Rodrigo, Peter Tidemand-Lichtenberg, Christian Pedersen
To the best of our knowledge, we present the first demonstration of short-wavelength infrared image upconversion that employs intense picosecond signal and pump beams. We use a fiber laser that emits a signal beam at 1877 nm and a pump beam at 1550 nm-both with a pulse width of 1 ps and a pulse repetition rate of 21.7 MHz. Due to synchronization of high peak-power pulses, efficient upconversion is achieved in a single-pass setup that employs a bulk lithium niobate crystal. Optimizing the temporal overlap of the pulses for high upconversion efficiency enables us to exploit a relatively large pump beam diameter to upconvert a wider range of signal spatial frequencies in the crystal...
February 1, 2017: Optics Letters
M Shcherbatenko, Y Lobanov, A Semenov, V Kovalyuk, A Korneev, R Ozhegov, A Kazakov, B M Voronov, G N Goltsman
Here, we report on the successful operation of a NbN thin film superconducting nanowire single-photon detector (SNSPD) in a coherent mode (as a mixer) at the telecommunication wavelength of 1550 nm. Providing the local oscillator power of the order of a few picowatts, we were practically able to reach the quantum noise limited sensitivity. The intermediate frequency gain bandwidth (also referred to as response or conversion bandwidth) was limited by the spectral band of a single-photon response pulse of the detector, which is proportional to the detector size...
December 26, 2016: Optics Express
E Petronijevic, C Sibilia
Electromagnetically induced transparency (EIT) is a pump-induced narrowband transparency window within an absorption line of the probe beam spectrum in an atomic system. In this paper we propose a way to bring together the all-dielectric metamaterials to have EIT-like effects and to optically tune the response by hybridizing them with a layer of a phase change material. We propose a design of the metamaterial based on Si nanoresonators that can support an EIT-like resonant response. On the top of the resonators we consider a thin layer of a chalcogenide phase change material, which we will use to tune the optical response...
December 26, 2016: Optics Express
Mohammad Karimi, Vahid Ahmadi, Masoud Ghezelsefloo
We demonstrate a novel design for optical fiber amplifiers, utilizing side-polished fibers with a single-layer graphene overlay as the active medium and carrier injection in the graphene layer to provide the required inversion. We study the effects of an electrically induced graphene p-i-n heterojunction in the forward bias regime on optical modes of side-polished fibers and show that gain values of 0.51, 1.81, and 1.79 dB/cm for wavelengths 1064, 1330, and 1550 nm can be obtained for single-mode side-polished fibers...
December 20, 2016: Applied Optics
Runze Chen, Yuhua Tang, Xin Zheng, Tian Jiang
Layered black phosphorus nanosheets (BPNs) offer potential uses in nanoelectronic and photonics applications. This work demonstrates giant saturable absorption (SA) and two-photon absorption (TPA) of BPNs under femtosecond visible-to-mid-infrared laser-pulse excitation. In addition, the excited carrier dynamics of BPNs were also studied with ultrafast pump-probe technology. Measurements demonstrated that the nonlinear absorption properties of BPNs strongly depend on excitation wavelength and intensity. BPNs moved from SA to TPA under increasing laser intensities at 800, 1160, 1300, and 1550 nm but showed a purely TPA response at 2000 nm, as gauged by measuring BPN nonlinear absorption coefficients...
December 20, 2016: Applied Optics
Christopher V Poulton, Matthew J Byrd, Manan Raval, Zhan Su, Nanxi Li, Erman Timurdogan, Douglas Coolbaugh, Diedrik Vermeulen, Michael R Watts
We demonstrate passive large-scale nanophotonic phased arrays in a CMOS-compatible silicon photonic platform. Silicon nitride waveguides are used to allow for higher input power and lower phase variation compared to a silicon-based distribution network. A phased array at an infrared wavelength of 1550 nm is demonstrated with an ultra-large aperture size of 4  mm×4  mm, achieving a record small and near diffraction-limited spot size of 0.021°×0.021° with a side lobe suppression of 10 dB. A main beam power of 400 mW is observed...
January 1, 2017: Optics Letters
Animesh Nayak, Jaehong Park, Kurt De Mey, Xiangqian Hu, Timothy V Duncan, David N Beratan, Koen Clays, Michael J Therien
Octopolar D2-symmetric chromophores, based on the MPZnM supermolecular motif in which (porphinato)zinc(II) (PZn) and ruthenium(II) polypyridyl (M) structural units are connected via ethyne linkages, were synthesized. These structures take advantage of electron-rich meso-arylporphyrin or electron-poor meso-(perfluoroalkyl)porphyrin macrocycles, unsubstituted terpyridyl and 4'-pyrrolidinyl-2,2';6',2″-terpyridyl ligands, and modulation of metal(II) polypyridyl-to-(porphinato)zinc connectivity, to probe how electronic and geometric factors impact the measured hyperpolarizability...
December 28, 2016: ACS Central Science
Yudong Cui, Feifei Lu, Xueming Liu
Monolayer of transition metal dichalcogenides (TMDs), with lamellar structure as that of graphene, has attracted significant attentions in optoelectronics and photonics. Here, we focus on the optical absorption response of a new member TMDs, rhenium disulphide (ReS2) whose monolayer and bulk forms have the nearly identical band structures. The nonlinear saturable and polarization-induced absorption of ReS2 are investigated at near-infrared communication band beyond its bandgap. It is found that the ReS2-covered D-shaped fiber (RDF) displays the remarkable polarization-induced absorption, which indicates the different responses for transverse electric (TE) and transverse magnetic (TM) polarizations relative to ReS2 plane...
January 5, 2017: Scientific Reports
Steven R Cohen, Ashley Goodacre, Soobin Lim, Jennifer Johnston, Cory Henssler, Brian Jeffers, Ahmad Saad, Tracy Leong
BACKGROUND: Fractional lasers were introduced to provide increased safety, while maintaining high efficacy and patient satisfaction. Patients with virtually all Fitzpatrick skin types could be safely treated using a wide spectrum of wavelengths and a broad array of skin conditions, and aging could be addressed. Although safety studies have been reported for ablative CO2 and erbium lasers, surprisingly few data are available on adverse events and complications associated with fractional lasers...
December 28, 2016: Aesthetic Plastic Surgery
Junhong Na, Kichul Park, Jin Tae Kim, Won Kook Choi, Yong-Won Song
We have demonstrated a few-layer black phosphorus (BP) phototransistor of stable operation in ambient air environment and at near-infrared light (λ = 1550 nm). The air-stable electronic and optoelectronic properties of the few-layer BP phototransistor have been achieved by a proper Al2O3 passivation. The optical identification method and qualitative and quantitative electrical characterizations of the few-layer BP phototransistor in dark state confirmed that the device performance was robust in ambient air, to further chemical treatments, and storage of more than six months...
December 28, 2016: Nanotechnology
Simon Bernard, Christoph Reinhardt, Vincent Dumont, Yves-Alain Peter, Jack C Sankey
Photonic crystal reflector (PCR) membranes exhibit a resonantly enhanced normal-incidence reflectivity. Many applications require this resonance to occur at a specific wavelength, however, imposing geometrical tolerances that are not reliably achieved with standard nanolithography. Here we finely tune the resonant wavelength of a freestanding Si<sub>3</sub>N<sub>4</sub> PCR membrane with iterative hydrofluoric acid etches, achieving a 57 nm thin crystal with a resonant wavelength 0.15 nm (0...
December 15, 2016: Optics Letters
W K Chang, H P Chung, Y Y Chou, R Geiss, S D Yang, T Pertsch, Y H Chen
We report on the first building of an active spectral narrowing mechanism in a pulsed, multiline optical parametric oscillator (OPO) based on a novel aperiodically poled lithium niobate (APPLN) device constructed using the aperiodic optical superlattice technique. The APPLN device functions simultaneously in the system as a multi-channel optical parametric down converter (OPDC) and an electro-optic (EO) gain spectral filter working on the corresponding (multiple) signal bands. When the APPLN OPO was installed in a diode pumped Nd:YVO<sub>4</sub> laser system, highly narrowed dual-wavelength signal lines (at 1540 and 1550 nm) were observed at the output of the system through EO control of the APPLN...
December 12, 2016: Optics Express
Sébastien Vigne, Nadir Hossain, Faezeh Fesharaki, S M Humayun Kabir, Joëlle Margot, Ke Wu, Mohamed Chaker
In this work, optical properties of epitaxial Ca<sub>x</sub>Ba<sub>1-x</sub>Nb<sub>2</sub>O<sub>6</sub>, CBN (x = 0.28) thin film based waveguides are studied at 1550 nm optical communications wavelength. CBN thin films are deposited epitaxially on MgO substrates using Pulsed Laser Deposition and characterized by prism coupling to extract the refractive index and propagation loss. It is shown that the 2 µm-thick epitaxial CBN thin films have a refractive index close to the bulk form and the CBN planar waveguides have a propagation loss of 4...
December 12, 2016: Optics Express
Shaoshuo Ma, Tigang Ning, Jing Li, Li Pei, Chuanbiao Zhang, Xiaodong Wen
This paper studies the bending effects on segmented cladding fibers (SCFs) in detail. Rod-type SCFs have offered large effective mode areas (EMAs) very successfully. The low-index segments in the design also enable the optical fibers to be bend-resistant. In this paper, the bending performance of the SCFs has been investigated by using the finite element method. The results indicate that SCFs can provide low-loss effective single-mode operation in a wide bandwidth under a bent configuration, due to the leakage losses of the higher-order modes (HOMs)...
December 10, 2016: Applied Optics
Zhi Liu, Hui Cong, Fan Yang, Chuanbo Li, Jun Zheng, Chunlai Xue, Yuhua Zuo, Buwen Cheng, Qiming Wang
GeSn is an attractive semiconductor material for Si-based photonics. However, large lattice mismatch between GeSn and Si and the low solubility of Sn in Ge limit its development. In order to obtain high Sn-content GeSn on Si, it is normally grown at low temperature, which would lead to inevitable dislocations. Here, we reported a single-crystal defect-free graded GeSn on insulator (GSOI) stripes laterally grown by rapid melting growth (RMG). The Sn-content reaches to 14.2% at the end of the GSOI stripe. Transmission electron microscopy observation shows the GSOI stripe without stacking fault and dislocations...
December 12, 2016: Scientific Reports
M L Reinke, M Han, G Liu, G G van Eden, R Evenblij, M Haverdings, B C Stratton
Measurements of radiated power in magnetically confined plasmas are important for exhaust studies in present experiments and expected to be a critical diagnostic for future fusion reactors. Resistive bolometer sensors have long been utilized in tokamaks and helical devices but suffer from electromagnetic interference (EMI). Results are shown from initial testing of a new bolometer concept based on fiber-optic temperature sensor technology. A small, 80 μm diameter, 200 μm long silicon pillar attached to the end of a single mode fiber-optic cable acts as a Fabry-Pérot cavity when broadband light, λo ∼ 1550 nm, is transmitted along the fiber...
November 2016: Review of Scientific Instruments
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