Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Thermally-Reconfigurable Quantum Photonic Circuits at Telecom Wavelength by Femtosecond Laser Micromachining  [PDF]
Fulvio Flamini,Lorenzo Magrini,Adil S. Rab,Nicolò Spagnolo,Vincenzo D'Ambrosio,Paolo Mataloni,Fabio Sciarrino,Tommaso Zandrini,Andrea Crespi,Roberta Ramponi,Roberto Osellame
Physics , 2015, DOI: 10.1038/lsa.2015.127
Abstract: The importance of integrated quantum photonics in the telecom band resides on the possibility of interfacing with the optical network infrastructure developed for classical communications. In this framework, femtosecond laser written integrated photonic circuits, already assessed for quantum information experiments in the 800 nm wavelength range, have great potentials. In fact these circuits, written in glass, can be perfectly mode-matched at telecom wavelength to the in/out coupling fibers, which is a key requirement for a low-loss processing node in future quantum optical networks. In addition, for several applications quantum photonic devices will also need to be dynamically reconfigurable. Here we experimentally demonstrate the high performance of femtosecond laser written photonic circuits for quantum experiments in the telecom band and we show the use of thermal shifters, also fabricated by the same femtosecond laser, to accurately tune them. State-of-the-art manipulation of single and two-photon states is demonstrated, with fringe visibilities greater than 95%. This opens the way to the realization of reconfigurable quantum photonic circuits on this technological platform.
Amplification Properties of Femtosecond Laser-Written Er3+/Yb3+ Doped Waveguides in a Tellurium-Zinc Glass  [PDF]
Massimo Olivero,Davinson Mariano da Silva,Luciana Reyes Pires Kassab,Anderson S. L. Gomes
Advances in Optical Technologies , 2013, DOI: 10.1155/2013/621018
Abstract: We report on the fabrication and characterization of active waveguides in a TeO2-ZnO glass sample doped with Er3+/Yb3+ fabricated by direct laser writing with a femtosecond laser delivering 150?fs pulses at 1?kHz repetition rate. The waveguides exhibit an internal gain of 0.6?dB/cm at 1535?nm, thus demonstrating the feasibility of active photonics lightwave circuits and lossless components in such a glass composition. 1. Introduction In the recent years, direct laser writing of waveguides and photonic lightwave circuits in glass and crystals has become a potential alternative to conventional fabrication methods such as ion exchange and lithography [1, 2]. The most prominent demonstrations of integrated optical devices for telecom applications have been realized by means of direct ultraviolet (UV) writing, exploiting UV coherent radiation to induce a permanent refractive index change into a glass substrate [3, 4]. This method has proved to be reliable and capable of competing with clean room processing in terms of waveguide loss, with the inherent advantage that laser writing enables fast prototyping and requires much lower ownership costs of fabrication. However, its widespread application has been hampered by the complexity of the writing procedure that requires plasma enhanced chemical vapor deposition (PECVD) glass substrates and hydrogen loading to enhance the photosensitivity. Furthermore, UV writing in bulk glass has been cumbersome and limited to two-dimensional structures. An extensive study of femtosecond (fs) laser pulses to locally modify the structure and refractive properties of optical glasses and other dielectrics via nonlinear absorption has been conducted in the recent years [5]. The mechanism undergoing this optically induced change is still a hot research topic, though it is believed that the process is triggered by a rapid absorption of the pulse energy through nonlinear excitation mechanisms [6]. Direct laser writing of optical waveguides and photonic lightwave circuits is currently one of the most widely studied applications of femtosecond (fs) laser micromachining in transparent dielectrics. Moreover, direct laser writing opens up new routes in fabrication of three-dimensional (3D) waveguides inside transparent glass substrates, which is otherwise impossible by conventional ion exchange and photolithographic processes [7]. Channel waveguides written using ultrafast lasers in erbium (Er) doped glasses and ytterbium/erbium (Yb/Er)-codoped glasses for integrated amplifiers and lasers operating in the C-band (1530–1565?nm) have been
Gallium Arsenide (GaAs) Quantum Photonic Waveguide Circuits  [PDF]
Jianwei Wang,Alberto Santamato,Pisu Jiang,Damien Bonneau,Erman Engin,Joshua W. Silverstone,Matthias Lermer,Johannes Beetz,Martin Kamp,Sven Hofling,Michael G. Tanner,Chandra M. Natarajan,Robert H. Hadfield,Sander N. Dorenbos,Val Zwiller,Jeremy L. O'Brien,Mark G. Thompson
Physics , 2014, DOI: 10.1016/j.optcom.2014.02.040
Abstract: Integrated quantum photonics is a promising approach for future practical and large-scale quantum information processing technologies, with the prospect of on-chip generation, manipulation and measurement of complex quantum states of light. The gallium arsenide (GaAs) material system is a promising technology platform, and has already successfully demonstrated key components including waveguide integrated single-photon sources and integrated single-photon detectors. However, quantum circuits capable of manipulating quantum states of light have so far not been investigated in this material system. Here, we report GaAs photonic circuits for the manipulation of single-photon and two-photon states. Two-photon quantum interference with a visibility of 94.9 +/- 1.3% was observed in GaAs directional couplers. Classical and quantum interference fringes with visibilities of 98.6 +/- 1.3% and 84.4 +/- 1.5% respectively were demonstrated in Mach-Zehnder interferometers exploiting the electro-optic Pockels effect. This work paves the way for a fully integrated quantum technology platform based on the GaAs material system.
A Directly-Written Monolithic Waveguide-Laser Incorporating a DFB Waveguide-Bragg Grating  [PDF]
Graham D. Marshall,Peter Dekker,Martin Ams,James A. Piper,Michael J. Withford
Physics , 2008, DOI: 10.1364/OL.33.000956
Abstract: We report the fabrication and performance of the first C-band directly-written monolithic waveguide-laser. The waveguide-laser device was created in an Erbium and Ytterbium doped phosphate glass host and consisted of an optical waveguide that included a distributed feedback Bragg grating structure. The femtosecond laser direct-write technique was used to create both the waveguide and the waveguide-Bragg grating simultaneously and in a single processing step. The waveguide-laser was optically pumped at approximately 980 nm and lased at 1537nm with a bandwidth of less than 4 pm.
Three-dimensional imaging of direct-written photonic structures  [PDF]
Graham D. Marshall,Alexander Jesacher,Anisha Thayil,Michael J. Withford,Martin Booth
Physics , 2010, DOI: 10.1364/OL.36.000695
Abstract: Third harmonic generation microscopy has been used to analyze the morphology of photonic structures created using the femtosecond laser direct-write technique. Three dimensional waveguide arrays and waveguide-Bragg gratings written in fused-silica and doped phosphate glass were investigated. A sensorless adaptive optical system was used to correct the optical aberrations occurring in the sample and microscope system, which had a lateral resolution of less than 500 nm. This non-destructive testing method creates volume reconstructions of photonic devices and reveals details invisible to other linear microscopy and index profilometry techniques.
Waveguide photon-number-resolving detectors for quantum photonic integrated circuits  [PDF]
D. Sahin,A. Gaggero,Z. Zhou,S. Jahanmirinejad,F. Mattioli,R. Leoni,J. Beetz,M. Lermer,M. Kamp,S. H?fling,A. Fiore
Physics , 2013, DOI: 10.1063/1.4820842
Abstract: Quantum photonic integration circuits are a promising approach to scalable quantum processing with photons. Waveguide single-photon-detectors (WSPDs) based on superconducting nanowires have been recently shown to be compatible with single-photon sources for a monolithic integration. While standard WSPDs offer single-photon sensitivity, more complex superconducting nanowire structures can be configured to have photon-number-resolving capability. In this work, we present waveguide photon-number-resolving detectors (WPNRDs) on GaAs/Al0.75Ga0.25As ridge waveguides based on a series connection of nanowires. The detection of 0-4 photons has been demonstrated with a four-wire WPNRD, having a single electrical read-out. A device quantum efficiency ~24 % is reported at 1310 nm for the TE polarization.
Hybrid vertical-cavity laser with lateral emission into a silicon waveguide  [PDF]
Gyeong Cheol Park,Weiqi Xue,Alireza Taghizadeh,Elizaveta Semenova,Kresten Yvind,Jesper M?rk,Il-Sug Chung
Physics , 2014,
Abstract: We experimentally demonstrate an optically-pumped III-V/Si vertical-cavity laser with lateral emission into a silicon waveguide. This on-chip hybrid laser comprises a distributed Bragg reflector, a III-V active layer, and a high-contrast grating reflector, which simultaneously funnels light into the waveguide integrated with the laser. This laser has the advantages of long-wavelength vertical-cavity surface-emitting lasers, such as low threshold and high side-mode suppression ratio, while allowing integration with silicon photonic circuits, and is fabricated using CMOS-compatible processes. It has the potential for ultrahigh-speed operation beyond 100 Gbit/s and features a novel mechanism for transverse mode control.
Combining Different in-Plane Photonic Wire Lasers and Coupling the Resulting Field Into a Single-Mode Waveguide
Md. Rezaur Raihan;Ziyuan Li;Danyu Liu;Haroldo T. Hattori;Malin Premaratne
PIER C , 2011, DOI: 10.2528/PIERC10112103
Abstract: Photonic wire lasers are compact light sources that are fabricated in high-index contrast waveguides (with typical widths of a few hundreds of nanometers). Because of their small footprints, they may become a basic laser component in future-generation of optical integrated circuits. Owing to having low optical volume by design, photonic wire lasers can only produce low output power that may not be adequate in many applications. A solution to this problem is to coherently combine the output power of different photonic wire lasers to produce larger output power. In this article, we analyze different ways to combine light coming out from photonic wire lasers and couple the combined power into a single-mode waveguide.
Investigation of ultrafast laser photonic material interactions: challenges for directly written glass photonics  [PDF]
M. Ams,G. D. Marshall,P. Dekker,M. Dubov,V. K. Mezentsev,I. Bennion,M. J. Withford
Physics , 2008, DOI: 10.1109/JSTQE.2008.925809
Abstract: Currently, direct-write waveguide fabrication is probably the most widely studied application of femtosecond laser micromachining in transparent dielectrics. Devices such as buried waveguides, power splitters, couplers, gratings and optical amplifiers have all been demonstrated. Waveguide properties depend critically on the sample material properties and writing laser characteristics. In this paper we discuss the challenges facing researchers using the femtosecond laser direct-write technique with specific emphasis being placed on the suitability of fused silica and phosphate glass as device hosts for different applications.
Three-dimensional quantum photonic elements based on single nitrogen vacancy-centres in laser-written microstructures  [PDF]
Andreas W. Schell,Johannes Kaschke,Joachim Fischer,Rico Henze,Janik Wolters,Martin Wegener,Oliver Benson
Physics , 2012, DOI: 10.1038/srep01577
Abstract: A fully integrated quantum optical technology requires active quantum systems incorporated into resonant optical microstructures and inter-connected in three dimensions via photonic wires. Nitrogen vacancy-centres (NV-centres) in diamond which are excellent photostable room temperature single-photon emitters are ideal candidates for that purpose. Extensive research efforts to couple NV-centres to photonic structures such as optical microresonators, microcavities, and waveguides have been pursued. Strategies for integration range from top-down fabrication via etching of diamond membranes to sophisticated bottom-up assembly of hybrid structures using diamond nanocrystals where the latter approach allows for deterministic coupling. Recently, another approach based on the incorporation of nanodiamonds in soft glass optical fibres via a melting process has been introduced. Here, we utilize two-photon direct laser writing (DLW) to fabricate fully three-dimensional (3D) structures from a photoresist mixed with a solution of nanodiamonds containing NV-centres. For the first time, this approach facilitates building integrated 3D quantum photonic elements of nearly arbitrary shapes.
Page 1 /100
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.