Read by QxMD icon Read

Optics Letters

Dimitris Mansour, Dimitris G Papazoglou
We show that through the use of optical aberrations, a reflective cylindrical beam expander can be properly adjusted to perform as a tunable ultra-broadband continuous phase modulation device. We demonstrate the effectiveness of such a device for the case of a net cubic phase modulation that is used to generate ultra-broadband white light 2D Airy beams. In this case, the nature of our device enables all spectral components to copropagate, following the same accelerating trajectory. The scalability of our approach, both in respect of input power and bandwidth, makes it possible to be used in any part of the electromagnetic spectrum...
November 1, 2018: Optics Letters
Seongjin Bak, Gyeong Hun Kim, Hansol Jang, Jeonghyo Kim, Jaebeom Lee, Chang-Seok Kim
We demonstrate a real-time surface plasmon resonance imaging (SPRi) system based on a wavelength-swept laser. Compared to conventional spectral-modulation SPRi using white light source and spectral filtering, the proposed system has a higher scan rate to detect rapid changes in refractive index and a higher output power for large-area illumination. This SPRi system achieves scan rates faster than 12 Hz, simultaneously obtaining SPR dip positions over full illumination fields of 12×12  mm. Using the wavelength-swept laser, two-dimensional biomolecular array imaging can be acquired with a high dynamic detection range (7...
November 1, 2018: Optics Letters
Adrià Escobet-Montalbán, Federico M Gasparoli, Jonathan Nylk, Pengfei Liu, Zhengyi Yang, Kishan Dholakia
We present the first demonstration of three-photon excitation light-sheet fluorescence microscopy. Light-sheet fluorescence microscopy in single- and two-photon modes has emerged as a powerful wide-field, low-photodamage technique for fast volumetric imaging of biological samples. We extend this imaging modality to the three-photon regime, enhancing its penetration depth. Our present study uses a conventional femtosecond pulsed laser at 1000 nm wavelength for the imaging of 450 μm diameter cellular spheroids...
November 1, 2018: Optics Letters
Jung-Shen B Tai, Ivan I Smalyukh
This publisher's note corrects errors in the body text of Opt. Lett.43, 5158 (2018)OPLEDP0146-959210.1364/OL.43.005158.
November 1, 2018: Optics Letters
Stefano Faralli, Fabrizio Gambini, Isabella Cerutti, Odile Liboiron-Ladouceur, Nicola Andriolli
A packaged photonic integrated network-on-chip (NoC) based on multi-microrings with a controller and scheduler implemented in FPGA is demonstrated under dynamic packet-switched traffic. Multiple transmission scenarios have been investigated, comprising up to three interfering signals at the same wavelength. The dynamic switching exhibits a power penalty of approximately 0.5 dB at a BER of 10-9 . The presence of up to three interferers induces a power penalty below 1 dB.
November 1, 2018: Optics Letters
Desmond M Chow, Luc Thévenaz
The standard single-mode fiber has been demonstrated as an optomechanical sensor recently to measure the acoustic impedances of surrounding liquids by means of the generation and detection of forward-stimulated Brillouin scattering (FSBS). FSBS allows the mechanical properties of an external material to be probed directly through the interaction of guided light and transverse sound waves that occurs entirely inside the fiber structure. In this technique, having a low-loss interface between the fiber bulk and the external medium is essential for precise measurement; however, it leads to the necessary but impractical removal of the thick polymer fiber coating in most reported methods...
November 1, 2018: Optics Letters
X Chai, X Ropagnol, A Ovchinnikov, O Chefonov, A Ushakov, C M Garcia-Rosas, E Isgandarov, M Agranat, T Ozaki, A Savel'ev
In this Letter, we investigate the nonlinear effects of extremely intense few-cycle terahertz (THz) pulses (generated from the organic crystal 4-NN, NN-dimethylamino-4' 4' -N' N' -methyl-stilbazolium 2, 4, 6 trimethylbenzenesulfonate, with peak electrical fields of a few MV/cm) on the carrier dynamics in n-doped semiconductor thin film In0.53 Ga0.47 As. By performing open-aperture Z-scan measurements and recording the transmitted THz energy through semiconductor sample, we observed a strong THz absorption bleaching effect at high fields, followed by an absorption enhancement at even higher fields...
November 1, 2018: Optics Letters
Xiangyu Quan, Manoj Kumar, Osamu Matoba, Yasuhiro Awatsuji, Yoshio Hayasaki, Satoshi Hasegawa, Hiroaki Wake
A new type of functional optical microscope system called three-dimensional (3D) stimulation and imaging-based functional optical microscopy (SIFOM) is proposed, to the best of our knowledge. SIFOM can precisely stimulate user-defined targeted biological cells and can simultaneously record the volumetric fluorescence distribution in a single acquisition. Precise and simultaneous stimulation of fluorescent-labeled biological cells is achieved by multiple 3D spots generated by digital holograms displayed on a phase-mode spatial light modulator...
November 1, 2018: Optics Letters
Lingling Yang, Zhe Kang, Bin Huang, Jie Li, Lili Miao, Pinghua Tang, Chujun Zhao, Guanshi Qin, Shuangchun Wen
We demonstrated passively Q-switched mid-infrared (mid-IR) erbium-doped fiber lasers by using gold nanostars (GNSs) as the Q-switcher. The nonlinear optical responses of the GNSs synthesized via the seed-mediated method have been characterized via a Z-scan technique, and the modulation depth and saturation intensity of the GNSs are measured to be 25% and 15.75  kW/cm2 , respectively. The Q-switched fiber laser can deliver a maximum average power of 454 mW with corresponding pulse energy of 3.6 μJ and pulse duration of 536 ns at a repetition rate of 125 kHz under the incident pump power 3...
November 1, 2018: Optics Letters
Stephen Hamann, Andrew Ceballos, Joe Landry, Olav Solgaard
We demonstrate a high-speed linear microelectromechanical systems (MEMS) phase modulator capable of random access scanning at 350 kHz, so that any state can be accessed in 2.9 μs from any other state. 670 scan lines with a .87 deg field of view (FOV) are demonstrated in a Fourier regime, with a projected far-field response of 660 lines with an 18 deg FOV after magnification.
November 1, 2018: Optics Letters
Shotaro Kitajima, Akira Shirakawa, Hideki Yagi, Takagimi Yanagitani
In this Letter, we demonstrate, to the best of our knowledge, the first Kerr-lens mode-locked (KLM) ceramic thin-disk laser. Ceramic laser gain media have many advantages for a high-power laser such as high fracture toughness, size scalability, low cost, and short time fabrication. By using the Yb:Lu2 O3 ceramic thin disk, the pulse duration of 98 fs with the output power of 3.7 W was demonstrated. The shortest pulse duration was 86 fs with the decreased output power of 0.36 W. From our results, it was proven that a KLM thin-disk laser with ceramic gain media can become a new option for high-power, sub-100 fs pulse laser sources...
November 1, 2018: Optics Letters
Jingjing Guo, Yuqing Luo, Changxi Yang, Lingjie Kong
Surface enhanced Raman scattering (SERS) fiber sensors have shown great potential in sensitive biosensing and medical diagnostics. However, current SERS fiber probes are most commonly based on stiff silica fibers, which, unfortunately, are not mechanically compliant with soft biological tissues. In addition, the poor biocompatibility of silica fibers sets another barrier that hinders their development for biomedical applications. Here, we present, to the best of our knowledge, the first demonstration of soft-polymer-optical-fiber-based SERS (SPOF-SERS) probes with physio-mechanical properties suitable for implantation, and demonstrate their potential applications for in situ detection of bioanalysts...
November 1, 2018: Optics Letters
Pei Zhou, Fangzheng Zhang, Daocheng Zhang, Shilong Pan
An approach to enhancing the performance of an optically-injected-semiconductor-laser-based optoelectronic oscillator (OEO) is proposed by subharmonic microwave modulation. A free-running OEO is first established based on period-one dynamics of an optically injected semiconductor laser. The oscillation frequency can be tuned in the range of 8.87 to 18.41 GHz by controlling the injection strength, but the output signal suffers from strong side modes and poor frequency stability. To address these problems, subharmonic microwave modulation is applied to the injected semiconductor laser...
November 1, 2018: Optics Letters
J Martinez-Carranza, T Kozacki
This Letter reports a method for tuning the degree of spatial coherence in an optical microscope. The method employs an amplitude spatial light modulator (aSLM) placed in the Fourier plane of the microscope. The aSLM displays a set of binary filters that blocks specific frequencies of the Fourier spectrum of the complex object field. It is shown that numerical processing of these filtered fields provides a final intensity with increased spatial coherence. Coherence tuning is used in a new hybrid phase reconstruction algorithm that employs the transport of intensity equation and an iterative phase retrieval technique...
November 1, 2018: Optics Letters
Ligang Huang, Wending Zhang, Yujia Li, Haonan Han, Xiaoting Li, Pengfa Chang, Feng Gao, Guoquan Zhang, Lei Gao, Tao Zhu
An acousto-optic tunable bandpass filter was proposed and fabricated based on acoustic-flexural-wave-induced single-mode fiber birefringence via coupling the core mode to a single-cladding vector mode. In the experiment, the resonant wavelength and insertion loss could be electrically tuned with a span of nearly 100 nm and a lowest insertion loss of -1.7  dB. The structure gains advantages of a large tuning range, fast speed, easy fabrication, low insertion loss, and zero frequency shift.
November 1, 2018: Optics Letters
Lyubov V Amitonova, Johannes F de Boer
We propose and experimentally demonstrate a new concept of endo-microscopy: compressive multimode (MM) fiber imaging. We show that the speckle patterns generated in a MM fiber represent an excellent basis for compressive sensing. We demonstrate high-resolution compressive imaging through a fiber probe with the total number of measurements 20 times less than what is required for the standard raster scanning approach to endo-microscopy. Moreover, we show that the inherent optical sectioning of a MM fiber can help to overcome the main problem of compressive sensing and can be used for the imaging of bulk structures...
November 1, 2018: Optics Letters
Robert B Kohlhaas, Roman J B Dietz, Steffen Breuer, Simon Nellen, Lars Liebermeister, Martin Schell, Björn Globisch
In this Letter, we report on photoconductive terahertz (THz) detectors for 1550 nm excitation based on a low-temperature-grown InGaAs/InAlAs superlattice with a localized beryllium doping profile. With this approach, we address the inherent lifetime-mobility trade-off that arises, since trapping centers also act as scattering sites for photo-excited electrons. The localized doping of the InAlAs barrier only leads to faster electron trapping for a given mobility. As a result, we obtain THz detectors with more than 6 THz bandwidths and 70 dB dynamic ranges (DNRs) at 3 THz and 55 dB DNR at 4 THz...
November 1, 2018: Optics Letters
Chau-Jern Cheng, Kuang-Che Chang Chien, Yu-Chih Lin
This study proposes a novel data augmentation method based on numerical focusing of digital holography to boost the performance of learning-based pattern classification. To conduct digital holographic data augmentation (DHDA), a complex pattern diffraction approach is used to provide the least separation of confusion in the effective diffraction regime to access the full-field wavefront information of a target sample. By using DHDA, the accessible amount of labeled data is increased to complement the data manifold and to provide various three-dimensional diffraction characteristics for improving the performance of learning-based pattern classification...
November 1, 2018: Optics Letters
Weifeng Zhang, Jianping Yao
A thermally tunable ultracompact Fano resonator on a silicon photonic chip is reported. The Fano resonator is implemented by using an add-drop microdisk resonator (MDR) with the through and drop ports connected by two waveguides and combined via an adiabatic 2×2, 3 dB coupler to form a Mach-Zehnder interferometer (MZI). Due to the resonant mode interference between the MDR and the MZI, a Fano resonance with an asymmetric line shape resulted. A p-type-doped microheater is incorporated in the MDR to achieve thermal tunability...
November 1, 2018: Optics Letters
Shaoping Shi, Yajun Wang, Wenhai Yang, Yaohui Zheng, Kunchi Peng
We report on a high-level squeezed vacuum state with maximum quantum noise reduction of 13.2 dB directly detected at the pump power of 180 mW. The pump power dependence of the squeezing factor is experimentally exhibited. When considering only loss and phase fluctuation, the fitting results have a large deviation from the measurement value near the threshold. By integrating green-light-induced infrared absorption (GLIIRA) loss, the squeezing factor can be perfectly fitted in the whole pump power range. The result indicates that GLIIRA loss should be thoroughly considered and quantified in the generation of high-level squeezed states...
November 1, 2018: Optics Letters
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"