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March


Fabrication of Cladded Self-Written Step Index Waveguides Using a One-Polymer Solution

  • Axel Günther, Ann Britt Petermann, Eduard Reithmeier, Uwe Gleissner, Thomas Hanemann, Maik Rahlves, Merve Wollweber, Uwe Morgner, and Bernhard Roth
  • received 01/14/2015; accepted 03/23/2015; posted 03/24/2015; Doc. ID 232402
  • [full text: PDF (746) KB)]
  • Abstract: Low-loss optical coupling structures are highly relevant for applications in fields as diverse as information and communication technologies, integrated circuits or exible and highly-functional polymer sensor networks, provided suitable and reliable production methods. Self-written waveguides are an interesting solution. However, it suffered from a fairly intricate and laborious formation of a mechanically rigid cladding and embedding structure. In this work we present a simple and efficient one polymer approach for self-written optical connections between light guiding structures such as single mode and multi mode optical fibers or waveguides which relies on self focusing of the light inside the polymer. The optical connections are produced in a two-step process by writing into polymer resin using cw laser light in the blue wavelength range and subsequent UV curing. We discuss the production method, the results obtained as function of relevant process parameters such as writing speed or curing time, and evaluate optical properties and coupling efficiencies.

Keywords (OCIS):

  • (060.1810) Fiber optics and optical communications : Buffers, couplers, routers, switches, and multiplexers
  • (060.2310) Fiber optics and optical communications : Fiber optics
  • (060.2340) Fiber optics and optical communications : Fiber optics components
  • (060.2360) Fiber optics and optical communications : Fiber optics links and subsystems
  • (230.7370) Optical devices : Waveguides
  • (130.5460) Integrated optics : Polymer waveguides

A smooth bridge between guided waves and designer surface plasmon polaritons

  • Zhuo Li, Liangliang Liu, Changqing Gu, Bingzheng Xu, Pingping Ning, Chen Chen, Jian Yan, Zhenyi Niu, and Yongjiu Zhao
  • received 12/15/2014; accepted 03/22/2015; posted 03/23/2015; Doc. ID 230609
  • [full text: PDF (1401) KB)]
  • Abstract: In this work, we build a smooth bridge between a coaxial waveguide and a plasmonic waveguide with subwavelength periodically cylindrical radial grooves, to realize high-efficiency mode conversion between conventional guided waves and designer surface plasmon polaritons in broadband. This bridge consists of a flaring coaxial waveguide connected with a metal cylindrical wire corrugated with subwavelength gradient radial grooves. Experimental results of the S-parameters show excellent agreement with the numerical simulations. The proposed scheme can be readily extended to other bands and the bridge structure can find potential applications in the integration of conventional microwave or terahertz devices with plasmonic circuits.

Keywords (OCIS):

  • (240.6680) Optics at surfaces : Surface plasmons
  • (350.4010) Other areas of optics : Microwaves
  • (250.5403) Optoelectronics : Plasmonics
  • (050.6624) Diffraction and gratings : Subwavelength structures

Ultra-compact TE-pass polarizer with graphene multilayer embedded in a silicon slot waveguide

  • Lin Chen, Xiang Yin, Tian Zhang, and Xun Li
  • received 02/04/2015; accepted 03/22/2015; posted 03/23/2015; Doc. ID 233885
  • [full text: PDF (688) KB)]
  • Abstract: A novel silicon slot waveguide TE-pass polarizer with graphene multilayer embedded in the slot is proposed and demonstrated by utilization of the fact that the variation of the modal characteristics for the TM mode is more than that for the TE mode. The designed polarizer is shown to have the ability to significantly suppress the transmission of the TM mode, while well guiding the TE mode. We demonstrate a 7-um-long polarizer has an ultra-high insertion loss of 31.5 dB for the TM mode and as little insertion loss as 0.2 dB for the TE mode at 1.55 um. The presented polarizer offers the performance merits including high extinction ratio, ultra-low insertion loss, ultra-compactness and easy integration with silicon slot waveguides without using any taper.

Keywords (OCIS):

  • (130.3120) Integrated optics : Integrated optics devices
  • (230.5440) Optical devices : Polarization-selective devices
  • (230.7370) Optical devices : Waveguides

Random Fabry–Pérot resonator based sub-kHz Brillouin fiber laser to improve spectral resolution in linewidth measurement

  • Yanping Xu, Dao Xiang, Zhonghua Ou, Ping Lu, and Xiaoyi Bao
  • received 02/09/2015; accepted 03/22/2015; posted 03/25/2015; Doc. ID 234219
  • [full text: PDF (666) KB)]
  • Abstract: For the first time we propose a novel Brillouin random fiber laser with a narrow linewidth of ~860 Hz based on the bi-directionally pumped stimulated Brillouin scattering (SBS) in a 10km long optical fiber. A random fiber Fabry-Perot (FP) resonator is built up through the pump depletion effects of SBS at both ends of the fiber. A theoretical model is developed to reveal the physics behind the unique random FP resonator which enables narrow random lasing emission. The novel laser is successfully applied for linewidth characterization beyond 860 Hz of light source under test.

Keywords (OCIS):

  • (060.2310) Fiber optics and optical communications : Fiber optics
  • (140.3490) Lasers and laser optics : Lasers, distributed-feedback

Generating polarization vortices by using helical beams and a Twyman Green interferometer

  • Shiyao FU, Chunqing GAO, Yang SHI, Dai Kunjian, Lei Zhong, and Shikun ZHANG
  • received 02/13/2015; accepted 03/21/2015; posted 03/23/2015; Doc. ID 234600
  • [full text: PDF (1108) KB)]
  • Abstract: A stable interferometric arrangement consisting of a polarizing beam splitter, a reflector and a right angle prism is designed to transform helical beams into polarization vortices. The computer-generated holograms are loaded on the liquid crystal spatial light modulator (LC-SLM) in order to generate different helical beams. Then the helical beams are transformed into polarization vortices with different kinds of intensity distribution successfully.

Keywords (OCIS):

  • (090.2890) Holography : Holographic optical elements
  • (260.5430) Physical optics : Polarization
  • (050.4865) Diffraction and gratings : Optical vortices

Photoluminescence spectra from quantum dots coupled to structured photonic reservoirs

  • Kaushik Roy Choudhury and Stephen Hughes
  • received 11/24/2014; accepted 03/21/2015; posted 03/23/2015; Doc. ID 228403
  • [full text: PDF (757) KB)]
  • Abstract: The spontaneous emission rate of a quantum dot coupled to a structured photonic reservoir is determined by the frequency dependence of its local density of photon states. Through phonon-dressing, a breakdown of Fermi's Golden rule can occur for certain photonic structures whose photon decay time become comparable to the acoustic phonon decay times. We present a polaron master equation model to describe photoluminsence spectra from a quantum dot coupled to a structured photonic reservoir. We consider specific examples of a semiconductor microcavity and a coupled cavity waveguide and show clear photoluminescence signatures that contain unique signatures of the interplay between phonon and photon bath coupling.

Keywords (OCIS):

  • (270.0270) Quantum optics : Quantum optics
  • (300.6470) Spectroscopy : Spectroscopy, semiconductors
  • (350.4238) Other areas of optics : Nanophotonics and photonic crystals

Mid-infrared lasing from Ho3+ in bulk InF3 glass

  • Antoine Berrou, Christelle Kieleck, and Marc Eichhorn
  • received 02/06/2015; accepted 03/20/2015; posted 03/20/2015; Doc. ID 234059
  • [full text: PDF (613) KB)]
  • Abstract: We report on a Ho3+:InF3 glass laser pumped by a Cr3+:LiSAF laser emitting at 889 nm. Ho3+:InF3 glass is a promising material for direct mid-infrared lasers around 4 μm. In order to evaluate the performances of this new material we compared it to a Ho3+:BYF crystalline laser pumped by the same source. At 650 mJ pump energy, 7.2 mJ (46 mJ) was obtained with Ho3+:InF3 (Ho3+:BYF), respectively. This is, to the best of our knowledge, thefifirst reported laser activity in this type of glass.

Keywords (OCIS):

  • (140.3070) Lasers and laser optics : Infrared and far-infrared lasers
  • (140.3380) Lasers and laser optics : Laser materials
  • (140.3580) Lasers and laser optics : Lasers, solid-state

Large mode area hybrid photonic crystal fiber amplifier at 1178 nm

  • Sidsel Petersen, Mingchen Chen, Akira Shirakawa, Christina Olausson, Thomas Alkeskjold, and Jesper Laegsgaard
  • received 11/13/2014; accepted 03/20/2015; posted 03/20/2015; Doc. ID 226799
  • [full text: PDF (1767) KB)]
  • Abstract: Amplification of 1178 nm light is demonstrated in a large mode area single-mode Ytterbium-doped hybrid photonic crystal fiber, relying on distributed spectral filtering of spontaneous emission at shorter wavelengths. An output power of 53 W is achieved with 29 dB suppression of parasitic lasing. Further power scaling is limited by parasitic lasing.

Keywords (OCIS):

  • (060.2320) Fiber optics and optical communications : Fiber optics amplifiers and oscillators
  • (060.5295) Fiber optics and optical communications : Photonic crystal fibers

Wavelength interrogation of fiber Bragg grating sensors based on crossed optical Gaussian filters

  • Li Xia, Rui Cheng, Dengming Liu, and Jiaao Zhou
  • received 11/18/2014; accepted 03/20/2015; posted 03/20/2015; Doc. ID 227030
  • [full text: PDF (349) KB)]
  • Abstract: Conventional intensity-modulated measurements require to be operated in linear range of filter or interferometric response to ensure a linear detection. Here, we present a wavelength interrogation system for fiber Bragg grating (FBG) sensors where the linear transition is achieved with crossed Gaussian transmissions. This unique filtering characteristic makes the responses of the two branch detections follow Gaussian functions with the same parameters except for a delay. The subtraction of these two delayed Gaussian responses (in dB) ultimately leads to a linear behavior, which is exploited for the sensor wavelength determination. Besides its flexibility and inherently power insensitivity, the proposal also shows a potential of a much wider operational range. Interrogation of a strain-tuned grating was accomplished, with a wide sensitivity tuning range from 2.56 to 8.7 dB/nm achieved.

Keywords (OCIS):

  • (060.2370) Fiber optics and optical communications : Fiber optics sensors
  • (060.3735) Fiber optics and optical communications : Fiber Bragg gratings

Multi-stability and polariton soliton formation in microcavity polaritonic waveguides

  • Gaby Slavcheva, Andrey Gorbach, Alexander Pimenov, A Vladimirov, and Dmitry Skryabin
  • received 02/18/2015; accepted 03/20/2015; posted 03/23/2015; Doc. ID 234915
  • [full text: PDF (980) KB)]
  • Abstract: Nonlinear polaritons in microcavity waveguides are demonstrated to exhibit multi-stable behaviour and rich dynamics, including filamentation and soliton formation. We find that the multi-stability originates from co-existence of different transverse modes of the polaritonic waveguide. Modulational stability and conditions for multi-mode polariton solitons are studied. Soliton propagation in tilted, relative to the pump momentum, waveguides is demonstrated and a critical tilt angle for the soliton propagation is found.

Keywords (OCIS):

  • (190.1450) Nonlinear optics : Bistability
  • (190.4720) Nonlinear optics : Optical nonlinearities of condensed matter
  • (190.5530) Nonlinear optics : Pulse propagation and temporal solitons
  • (190.5970) Nonlinear optics : Semiconductor nonlinear optics including MQW
  • (230.3120) Optical devices : Integrated optics devices
  • (190.4975) Nonlinear optics : Parametric processes

Temperature-insensitivity gas pressure sensor based on inflated long period fiber grating inscribed in photonic crystal fiber

  • Yiping Wang, Xiaoyong Zhong, Changrui Liao, Shen Liu, Jian Tang, and Qiao Wang
  • received 01/16/2015; accepted 03/20/2015; posted 03/24/2015; Doc. ID 232588
  • [full text: PDF (1354) KB)]
  • Abstract: We demonstrated an inflated long period fiber grating (I-LPFG) inscribed in a pure-silica photonic crystal fiber (PCF) for high-sensitivity gas pressure sensing applications. The I-LPFG was inscribed by use of the pressure-assisting CO2 laser beam scanning technique to inflate periodically air holes of a PCF along the fiber axis. Such an I-LPFG with periodic inflations exhibits a very high gas pressure sensitivity of ~1.68 nm/MPa, which is one order of magnitude higher than that, i.e. 0.12 nm/Mpa, of the LPFG without periodic inflations. Moreover, the I-LPFG has a very low temperature sensitivity of 2.8 pm/°C due to the pure silica material in the PCF so that the pressure measurement error, resulting from the cross sensitivity between temperature and gas pressure, is less than 1.7 Kpa/°C in the case of no temperature compensation. So the I-LPFG could be used to develop a promising gas pressure sensor, and the achieved pressure measurement range is up to 10 MPa.

Keywords (OCIS):

  • (050.2770) Diffraction and gratings : Gratings
  • (060.2340) Fiber optics and optical communications : Fiber optics components
  • (060.2370) Fiber optics and optical communications : Fiber optics sensors
  • (060.5295) Fiber optics and optical communications : Photonic crystal fibers

Asymmetric dwell-time statistics of polarization chaos from free-running VCSEL

  • Martin Virte, Krassimir Panajotov, Elodie Mirisola, and Marc Sciamanna
  • received 03/06/2015; accepted 03/20/2015; posted 03/25/2015; Doc. ID 235610
  • [full text: PDF (624) KB)]
  • Abstract: We experimentally report on asymmetric dwell-time statistics of polarization chaos dynamics generated from free-running VCSELs. Theoretically, we explain this behaviour by introducing a misalignment between the phase and amplitude anisotropy within the spin-flip VCSEL model. While a small misalignment will only have a limited impact on the dynamics, a strong misalignment lead to significant changes in the statistics of the chaotic mode-hopping with an increase of the average residence time and an inversion of the dominant mode.

Keywords (OCIS):

  • (140.1540) Lasers and laser optics : Chaos
  • (140.5960) Lasers and laser optics : Semiconductor lasers
  • (140.7260) Lasers and laser optics : Vertical cavity surface emitting lasers

On the Measurement of the Pockels Effect in Strained Silicon

  • Jeremy Witzens, Florian Merget, M. Saeed Sharif Azadeh, and Maziar Nezhad
  • received 03/09/2015; accepted 03/20/2015; posted 03/25/2015; Doc. ID 235732
  • [full text: PDF (2417) KB)]
  • Abstract: We measure the voltage dependent phase shift in silicon waveguides strained by a silicon nitride layer and show that, in our measurements, the phase shift is due to free carrier accumulation inside the waveguides. Even though the effect is due to carrier accumulation, inverting the applied voltage also inverts the applied phase shift – an effect due to a quasi-static surface charge in the silicon nitride. Since the measured effect is on the same order as recently published second order nonlinearities attributed to the Pockels effect, inclusion of these carrier based effects in the analysis of experimental data is of paramount importance.

Keywords (OCIS):

  • (160.3130) Materials : Integrated optics materials
  • (190.5970) Nonlinear optics : Semiconductor nonlinear optics including MQW
  • (250.7360) Optoelectronics : Waveguide modulators

Single-mode Master-Oscillator Power-Amplifier at 647nm with more than 500 mW output power

  • Gunnar Blume, Johannes Pohl, David Feise, Maik Jendrzejewski, Marcel Greiner, Peter Ressel, and Katrin Paschke
  • received 02/04/2015; accepted 03/19/2015; posted 03/23/2015; Doc. ID 234060
  • [full text: PDF (308) KB)]
  • Abstract: Using an AlGaInP-based truncated tapered power amplifier it was possible to boost the output power of a 647 nm distributed Bragg reflector laser from 50 mW to more than 500 mW. The light source has the potential to replace bulky Kr ion lasers still in use at this wavelength.

Keywords (OCIS):

  • (090.0090) Holography : Holography
  • (120.3180) Instrumentation, measurement, and metrology : Interferometry
  • (140.2020) Lasers and laser optics : Diode lasers
  • (140.4480) Lasers and laser optics : Optical amplifiers
  • (140.7300) Lasers and laser optics : Visible lasers
  • (300.3700) Spectroscopy : Linewidth

An optical driven electromechanical transistor based on tunneling effect

  • Lijie Li and Leisheng Jin
  • received 01/30/2015; accepted 03/19/2015; posted 03/23/2015; Doc. ID 233583
  • [full text: PDF (464) KB)]
  • Abstract: A new electromechanical transistor operated based on an optical driven vibrational ring structure has been postulated. In the device, optical power excites the ring structure to vibrate, which acts as the shuttle transporting electrons from one electrode to the other forming the transistor. The electrical current of the transistor is adjusted by the optical power. Coupled opto-electro-mechanical simulation has been performed. It is shown from the dynamic analysis that the stable working range of the transistor is much wider than that of the optical wave inside the cavity, i.e. the optical resonance enters non-periodic states while the mechanical vibration of the ring is still periodic.

Keywords (OCIS):

  • (230.2090) Optical devices : Electro-optical devices
  • (230.3990) Optical devices : Micro-optical devices
  • (230.4910) Optical devices : Oscillators
  • (230.4685) Optical devices : Optical microelectromechanical devices

Laser oscillation in Yb:YAG waveguide beam-splitters with variable splitting ratio

  • Thomas Calmano, Christian Kraenkel, and Guenter Huber
  • received 02/20/2015; accepted 03/18/2015; posted 03/20/2015; Doc. ID 235047
  • [full text: PDF (1347) KB)]
  • Abstract: In this paper we report about laser emission from Yb:YAG beam-splitters fabricated by direct femtosecond-laser inscription. These devices consist of two adjacent mirrored s-curved waveguides merged into a section allowing for multi-mode interference (MMI) and a straight waveguide. Nine millimeter long one-to-two beam-splitters with radii of curvature between 10 and 80 mm have been fabricated resulting in separations between the two arms of up to 0.65 mm. Due to the MMI-section the splitting ratio was variable by slightly changing the incoupling conditions. Maximum laser output powers of 2.29 W and slope efficiencies of 52% were achieved with the best beam-splitter waveguide laser. For all radii of curvature exceeding 10 mm similar efficiencies were demonstrated.

Keywords (OCIS):

  • (130.3120) Integrated optics : Integrated optics devices
  • (230.7380) Optical devices : Waveguides, channeled
  • (140.3615) Lasers and laser optics : Lasers, ytterbium
  • (130.3990) Integrated optics : Micro-optical devices

Absolute near infrared refractometry with a calibrated tilted fiber Bragg grating

  • Wenjun Zhou, David Mandia, Sean Barry, and Jacques Albert
  • received 02/13/2015; accepted 03/18/2015; posted 03/18/2015; Doc. ID 233698
  • [full text: PDF (1013) KB)]
  • Abstract: The absolute refractive index (RI) of water and other liquids are determined with an uncertainty of ± 0.001 at near infrared wavelengths by using the tilted fiber Bragg grating (TFBG) cladding mode resonances of a standard single mode fiber (SMF) to measure the critical angle for total internal reflection at the interface between the fiber and its surroundings. The necessary condition to obtain absolute RIs (instead of measuring RI changes) is a thorough characterization of the dispersion of the core mode effective index of the TFBG across the full range of its cladding mode resonance spectrum. This technique is shown to be competitive with the best available measurements of the RIs of water and NaCl solutions at wavelengths in the vicinity of 1550 nm.

Keywords (OCIS):

  • (060.2370) Fiber optics and optical communications : Fiber optics sensors
  • (060.2400) Fiber optics and optical communications : Fiber properties
  • (060.3735) Fiber optics and optical communications : Fiber Bragg gratings

Shaping optical beams with non-integer orbital angular momentum: a generalized differential operator approach

  • Julio Gutierrez-Vega and Israel Martinez-Castellanos
  • received 12/08/2014; accepted 03/18/2015; posted 03/19/2015; Doc. ID 229244
  • [full text: PDF (1057) KB)]
  • Abstract: We introduce an analytical procedure to construct an optical beam with an arbitrary value of orbital angular momentum (OAM) by keeping the flexibility of shaping its transverse intensity distribution without changing its OAM. We apply the general theory of fractional differential operators in Fourier domain to derive general expressions for the OAM content in the beam and find the relevant parameters that determine its OAM value and those that can be freely modified without affecting it.

Keywords (OCIS):

  • (050.1960) Diffraction and gratings : Diffraction theory
  • (350.5500) Other areas of optics : Propagation
  • (070.3185) Fourier optics and signal processing : Invariant optical fields
  • (070.7345) Fourier optics and signal processing : Wave propagation

Monolithic Sixteen Wavelength Selector Based on a Chain of Passband-Flattened Cyclic AWGs and Optical Switches

  • Ripalta Stabile, Nicola Calabretta, Kevin Williams, and Harmen Dorren
  • received 12/24/2014; accepted 03/18/2015; posted 03/19/2015; Doc. ID 231305
  • [full text: PDF (1368) KB)]
  • Abstract: An InP monolithically integrated wavelength selector based on combinations of integrated AWGs and SOAs selects one out of up to 16 input channels. Loss-compensated, error-free WDM channel selection operation with <2.3 dB penalties is reported, with an OSNR of up to 32.5 dB/0.1nm.

Keywords (OCIS):

  • (250.5300) Optoelectronics : Photonic integrated circuits
  • (250.5980) Optoelectronics : Semiconductor optical amplifiers

4D Optical Coherence Tomography based Microangiography achieved by 1.6 MHz FDML Swept source

  • Ruikang Wang, Qin Wan, Wei Wei, Jingang Wang, and Zhongwei Zhi
  • received 02/09/2015; accepted 03/17/2015; posted 03/18/2015; Doc. ID 234101
  • [full text: PDF (764) KB)]
  • Abstract: We demonstrate the use of an ultra-high speed swept-source optical coherence tomography (OCT) to achieve optical microangiography (OMAG) of microcirculatory tissue beds in vivo. The system is based on a 1310 nm Fourier domain mode locking (FDML) laser with 1.6 MHz A-line rate, providing a frame rate of 3.415 KHz, an axial resolution of ~10 µm and signal to noise ratio of 115 dB. Motion from blood flow causes change in OCT signals between consecutive B-frames acquired at the same location. Intensity based inter-frame subtraction algorithm is applied to extract blood flow from tissue background without any motion correction. We demonstrate the capability of this 1.6 MHz OCT system for 4D optical microangiography of in vivo tissue at a volume rate of 4.7 volumes/s (volume size: 512×200×720 voxels).

Keywords (OCIS):

  • (110.0110) Imaging systems : Imaging systems
  • (110.4500) Imaging systems : Optical coherence tomography
  • (170.0170) Medical optics and biotechnology : Medical optics and biotechnology
  • (170.3880) Medical optics and biotechnology : Medical and biological imaging

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