共查询到20条相似文献,搜索用时 31 毫秒
1.
Motoki Asano Yuki Takeuchi Weijian Chen ahin Kaya
zdemir Rikizo Ikuta Nobuyuki Imoto Lan Yang Takashi Yamamoto 《Laser \u0026amp; Photonics Reviews》2016,10(4):603-611
In this work, we report optomechanical coupling, resolved sidebands and phonon lasing in a solid‐core microbottle resonator fabricated on a single mode optical fiber. Mechanical modes with quality factors (Qm) as high as 1.57 × 104 and 1.45 × 104 were observed, respectively, at the mechanical frequencies and . The maximum Hz is close to the theoretical lower bound of 6 × 1012 Hz needed to overcome thermal decoherence for resolved‐sideband cooling of mechanical motion at room temperature, suggesting microbottle resonators as a possible platform for this endeavor. In addition to optomechanical effects, scatter‐induced mode splitting and ringing phenomena, which are typical for high‐quality optical resonances, were also observed in a microbottle resonator.
2.
Tom Neuman Pablo Alonso‐Gonzlez Aitzol Garcia‐Etxarri Martin Schnell Rainer Hillenbrand Javier Aizpurua 《Laser \u0026amp; Photonics Reviews》2015,9(6):637-649
Near‐field optical microscopy techniques provide information on the amplitude and phase of local fields in samples of interest in nanooptics. However, the information on the near field is typically obtained by converting it into propagating far fields where the signal is detected. This is the case, for instance, in polarization‐resolved scattering‐type scanning near‐field optical microscopy (s‐SNOM), where a sharp dielectric tip scatters the local near field off the antenna to the far field. Up to now, basic models have interpreted S‐ and P‐polarized maps obtained in s‐SNOM as directly proportional to the in‐plane ( or ) and out‐of‐plane () near‐field components of the antenna, respectively, at the position of the probing tip. Here, a novel model that includes the multiple‐scattering process of the probing tip and the nanoantenna is developed, with use of the reciprocity theorem of electromagnetism. This novel theoretical framework provides new insights into the interpretation of s‐SNOM near‐field maps: the model reveals that the fields detected by polarization‐resolved interferometric s‐SNOM do not correlate with a single component of the local near field, but rather with a complex combination of the different local near‐field components at each point (, and ). Furthermore, depending on the detection scheme (S‐ or P‐polarization), a different scaling of the scattered fields as a function of the local near‐field enhancement is obtained. The theoretical findings are corroborated by s‐SNOM experiments which map the near field of linear and gap plasmonic antennas. This new interpretation of nanoantenna s‐SNOM maps as a complex‐valued combination of vectorial local near fields is crucial to correctly understand scattering‐type near‐field microscopy measurements as well as to interpret the signals obtained in field‐enhanced spectroscopy.
3.
Open‐access microcavities are emerging as a new approach to confine and engineer light at mode volumes down to the λ3 regime. They offer direct access to a highly confined electromagnetic field while maintaining tunability of the system and flexibility for coupling to a range of matter systems. This article presents a study of coupled cavities, for which the substrates are produced using Focused Ion Beam milling. Based on experimental and theoretical investigation the engineering of the coupling between two microcavities with radius of curvature of 6 m is demonstrated. Details are provided by studying the evolution of spectral, spatial and polarisation properties through the transition from isolated to coupled cavities. Normal mode splittings up to 20 meV are observed for total mode volumes around . This work is of importance for future development of lab‐on‐a‐chip sensors and photonic open‐access devices ranging from polariton systems to quantum simulators.
4.
Irina Khromova Petr Kuel Igal Brener John L. Reno U‐Chan Chung Seu Catherine Elissalde Mario Maglione Patrick Mounaix Oleg Mitrofanov 《Laser \u0026amp; Photonics Reviews》2016,10(4):681-687
Monocrystalline titanium dioxide (TiO2) micro‐spheres support two orthogonal magnetic dipole modes at terahertz (THz) frequencies due to strong dielectric anisotropy. For the first time, we experimentally detected the splitting of the first Mie mode in spheres of radii m through near‐field time‐domain THz spectroscopy. By fitting the Fano lineshape model to the experimentally obtained spectra of the electric field detected by the sub‐wavelength aperture probe, we found that the magnetic dipole resonances in TiO2 spheres have narrow linewidths of only tens of gigahertz. Anisotropic TiO2 micro‐resonators can be used to enhance the interplay of magnetic and electric dipole resonances in the emerging THz all‐dielectric metamaterial technology.
5.
Xin Gai Yi Yu Bart Kuyken Pan Ma Steve J. Madden Joris Van Campenhout Peter Verheyen Gunther Roelkens Roel Baets Barry Luther‐Davies 《Laser \u0026amp; Photonics Reviews》2013,7(6):1054-1064
The wavelength dependence of the nonlinear absorption and the third order nonlinear refraction of crystalline silicon between m and m as well as at m have been measured. It was found that at all wavelengths multi‐photon and free carrier absorption can be significant. In particular nonlinear absorption can affect silicon devices designed for the mid‐infrared that require strong nonlinear response, such as for the generation of a supercontinuum. 相似文献
6.
Yaroslav V. Kartashov Chao Hang Vladimir V. Konotop Victor A. Vysloukh Guoxiang Huang Lluis Torner 《Laser \u0026amp; Photonics Reviews》2016,10(1):100-107
We uncover that the breaking point of the ‐symmetry in optical waveguide arrays has a dramatic impact on light localization induced by the off‐diagonal disorder. Specifically, when the gain/loss control parameter approaches a critical value at which ‐symmetry breaking occurs, a fast growth of the coupling between neighboring waveguides causes diffraction to dominate to an extent that light localization is strongly suppressed and the statistically averaged width of the output pattern substantially increases. Beyond the symmetry‐breaking point localization is gradually restored, although in this regime the power of localized modes grows upon propagation. The strength of localization monotonically increases with disorder at both broken and unbroken ‐symmetry. Our findings are supported by statistical analysis of parameters of stationary eigenmodes of disordered‐symmetric waveguide arrays and by analysis of dynamical evolution of single‐site excitations in such structures.
7.
Sebastian Keppler Alexander Svert Jrg Krner Marco Hornung Hartmut Liebetrau Joachim Hein Malte Christoph Kaluza 《Laser \u0026amp; Photonics Reviews》2016,10(2):264-277
An analytical model is presented describing the temporal intensity contrast determined by amplified spontaneous emission in high‐intensity laser systems which are based on the principle of chirped pulse amplification. The model describes both the generation and the amplification of the amplified spontaneous emission for each type of laser amplifier. This model is applied to different solid state laser materials which can support the amplification of pulse durations . The results are compared to intensity and fluence thresholds, e.g. determined by damage thresholds of a certain target material to be used in high‐intensity applications. This allows determining if additional means for contrast improvement, e.g. plasma mirrors, are required for a certain type of laser system and application. Using this model, the requirements for an optimized high‐contrast front‐end design are derived regarding the necessary contrast improvement and the amplified “clean” output energy for a desired focussed peak intensity. Finally, the model is compared to measurements at three different high‐intensity laser systems based on Ti:Sapphire and Yb:glass. These measurements show an excellent agreement with the model.
8.
Stefania Dante Daphn Duval David Faria Ana Beln Gonzlez‐Guerrero Laura M. Lechuga 《Laser \u0026amp; Photonics Reviews》2015,9(2):248-255
An all‐optical phase modulation method for the linear readout of integrated interferometric biosensors is demonstrated, merging simple intensity detection with the advantages offered by spectral interrogation. The phase modulation is introduced in a simple and cost‐effective way by tuning a few nanometers the emission wavelength of commercial laser diodes, taking advantage of their well‐known drawback of power–wavelength dependence. The method is applied to the case of a bimodal waveguide (BiMW) interferometric biosensor, fabricated with standard silicon technology and operated at visible wavelengths, rendering a detection limit of refractive index units for bulk sensing. The biosensing capabilities of the phase‐linearized BiMW device are assessed through the quantitative immunoassay of C‐reactive protein, a key protein in inflammatory processes. This method can be applied to any modal interferometer.
9.
Yiqi Zhang Hua Zhong Milivoj R. Beli Yi Zhu Weiping Zhong Yanpeng Zhang Demetrios N. Christodoulides Min Xiao 《Laser \u0026amp; Photonics Reviews》2016,10(3):526-531
We investigate the fractional Schrödinger equation with a periodic ‐symmetric potential. In the inverse space, the problem transfers into a first‐order nonlocal frequency‐delay partial differential equation. We show that at a critical point, the band structure becomes linear and symmetric in the one‐dimensional case, which results in a nondiffracting propagation and conical diffraction of input beams. If only one channel in the periodic potential is excited, adjacent channels become uniformly excited along the propagation direction, which can be used to generate laser beams of high power and narrow width. In the two‐dimensional case, there appears conical diffraction that depends on the competition between the fractional Laplacian operator and the ‐symmetric potential. This investigation may find applications in novel on‐chip optical devices.
10.
A necessary condition for generation of bright soliton Kerr frequency combs in microresonators is to achieve anomalous group velocity dispersion (GVD) for the resonator modes. This condition is hard to implement in the visible as well as ultraviolet since the majority of optical materials are characterized with large normal GVD in these wavelength regions. We overcome this challenge by borrowing ideas from strongly dispersive coupled systems in solid state physics and optics. We show that photonic compound ring resonators can possess large anomalous GVD at any desirable wavelength, even if each individual resonator is characterized with normal GVD. Based on this concept, we design a mode‐locked frequency comb with thin‐film silicon nitride compound ring resonators in the vicinity of the rubidium D1 line (794.6 nm) and propose to use this optical comb as a flywheel for chip‐scale optical clocks.
11.
12.
Xiaoxiao Xue Yi Xuan Pei‐Hsun Wang Yang Liu Dan E. Leaird Minghao Qi Andrew M. Weiner 《Laser \u0026amp; Photonics Reviews》2015,9(4):L23-L28
We demonstrate a scheme incorporating dual‐coupled microresonators through which mode interactions are intentionally introduced and controlled for Kerr frequency comb (microcomb) generation in the normal‐dispersion region. Microcomb generation, repetition rate selection, and mode locking are achieved with coupled silicon nitride microrings controlled via an on‐chip microheater. The proposed scheme shows for the first time a reliable design strategy for normal‐dispersion microcombs and may make it possible to generate microcombs in an extended wavelength range (e.g. in the visible) where normal material dispersion is likely to dominate.
13.
Simon Gross Nicolas Riesen John D. Love Michael J. Withford 《Laser \u0026amp; Photonics Reviews》2014,8(5):L81-L85
The demonstration of a three‐dimensional tapered mode‐selective coupler in a photonic chip is reported. This waveguide‐based, ultra‐broadband mode multiplexer was fabricated using the femtosecond laser direct‐write technique in a boro‐aluminosilicate glass chip. A three‐core coupler has been shown to enable the multiplexing of the LP01, LP and LP spatial modes of a multimode waveguide, across an extremely wide bandwidth exceeding 400 nm, with low loss, high mode extinction ratios and negligible mode crosstalk. Linear cascades of such devices on a single photonic chip have the potential to become a definitive technology in the realization of broadband mode‐division multiplexing for increasing optical fiber capacity. 相似文献
14.
This article presents a novel III‐V on silicon laser. This work exploits the phenomenon that a passive silicon cavity, side‐coupled to a III‐V waveguide, will provide high and narrow‐band reflectivity into the III‐V waveguide: the resonant mirror. This results in an electrically pumped laser with a threshold current of 4 mA and a side‐mode suppression ratio up to 48 dB.
15.
Gediminas Gervinskas Gediminas Seniutinas Saulius Juodkazis 《Laser \u0026amp; Photonics Reviews》2013,7(6):1049-1053
The universal problem of surface charging during focused ion milling has been fully resolved using a flood‐gun approach based on simultaneous co‐illumination with a UV light‐emitting diode (LED). Non‐distorted as‐designed nano‐patterns were milled using Ga+ ions on dielectric materials which charge up strongly. Deep‐UV (250–280 nm) LED co‐illumination during the ion beam milling fully discharges optically the surface under standard Ga+ ion‐milling conditions. Photo‐ionization of electrons trapped at the sub‐surface defects to the free vacuum state is a key to the phenomenon ( nm corresponds to a photon energy eV). The method is applicable as a solution to other charging problems where electrons (primary or secondary) and their spatial redistribution affect nanofabrication or imaging. 相似文献
16.
Mikhail Y. Shalaginov Vadim V. Vorobyov Jing Liu Marcello Ferrera Alexey V. Akimov Alexei Lagutchev Andrey N. Smolyaninov Vasily V. Klimov Joseph Irudayaraj Alexander V. Kildishev Alexandra Boltasseva Vladimir M. Shalaev 《Laser \u0026amp; Photonics Reviews》2015,9(1):120-127
The broadband enhancement of single‑photon emission from nitrogen‐vacancy centers in nanodiamonds coupled to a planar multilayer metamaterial with hyperbolic dispersion is studied experimentally. The metamaterial is fabricated as an epitaxial metal/dielectric superlattice consisting of CMOS‐compatible ceramics: titanium nitride (TiN) and aluminum scandium nitride (AlxSc1‐xN). It is demonstrated that employing the metamaterial results in significant enhancement of collected single‑photon emission and reduction of the excited‐state lifetime. Our results could have an impact on future CMOS‐compatible integrated quantum sources.
17.
Alexander A. Kaminskii Oliver Lux Hanjo Rhee Hans‐Joachim Eichler Hitoki Yoneda Akita Shirakawa Petra Becker Ladislav Bohatý 《Laser \u0026amp; Photonics Reviews》2014,8(2):324-331
In single crystals of the beryllium silicate Be2SiO4 with trigonal symmetry , known also as the mineral phenakite, χ(3)‐nonlinear lasing by stimulated Raman scattering (SRS) is investigated. All observed Stokes and anti‐Stokes lasing components are identified and ascribed to a single SRS‐promoting vibration mode with ωSRS ≈876 cm−1. With picosecond single‐wavelength pumping at one micrometer the generation of an octave‐spanning Stokes and anti‐Stokes comb is observed. 相似文献
18.
Cheng Zhang Carl Pfeiffer Taehee Jang Vishva Ray Maxwell Junda Prakash Uprety Nikolas Podraza Anthony Grbic L. Jay Guo 《Laser \u0026amp; Photonics Reviews》2016,10(5):791-798
High efficiency, broad bandwidth, and robust angular tolerance are key considerations in photonic device design. Here, a few‐layer, asymmetric light transmitting metasurface that simultaneously satisfies all the above requirements is reported. The metasurface consists of coupled metallic sheets. It has a measured transmission efficiency of 80%, extinction ratio of 13.8 dB around 1.5 μm, and a full width half maximum bandwidth of 1.7 μm. It is as thin as 290 nm, has good performance tolerance against the angle of incidence and constituent nano‐structure geometry variations. This work demonstrates a practical asymmetric light transmission device with optimal performance for large scale manufacturing.
19.
Y. F. Chen M. T. Chang W. Z. Zhuang K. W. Su K. F. Huang H. C. Liang 《Laser \u0026amp; Photonics Reviews》2015,9(1):91-97
A novel scheme to multiply the repetition rate of a monolithic self‐mode‐locked laser for generating sub‐terahertz pulse sources is successfully demonstrated. A coated Yb:KGW crystal is designed to achieve a self‐mode‐locked operation at a repetition rate of 24 GHz with an average output power exceeding 1.0 W at a pump power of 4.8 W. A partially reflective mirror is utilized to combine with the output surface of the gain medium to constitute an external Fabry‐Perot cavity. It is theoretically and experimentally verified that adjusting the external cavity length to satisfy the commensurate condition can lead to the frequency spacing to be various order harmonics of the mode spacing of the monolithic cavity. The maximum pulse repetition rate of the laser output can be up to 216 GHz and the pulse duration is as short as 330 fs. More importantly, the overall characteristics of the first‐order temporal autocorrelation traces obtained by sequentially scanning the external cavity.length display an intriguing phenomenon of temporally fractional revivals, similar to the feature of spatial Talbot revivals.
20.
Enhanced emission extraction and selective excitation of NV centers with all–dielectric nanoantennas
Alexander E. Krasnok Alex Maloshtan Dmitry N. Chigrin Yuri S. Kivshar Pavel A. Belov 《Laser \u0026amp; Photonics Reviews》2015,9(4):385-391
A novel approach to facilitate excitation and readout processes of isolated negatively charged nitrogen‐vacancy (NV) centers is proposed. The approach is based on the concept of all‐dielectric nanoantennas. It is shown that the all‐dielectric nanoantenna can significantly enhance both the emission rate and emission extraction efficiency of a photoluminescence signal from a single NV center in a diamond nanoparticle on a dielectric substrate. The proposed approach provides high directivity, large Purcell factor, and efficient beam steering, thus allowing an efficient far‐field initialization and readout of several NV centers separated by subwavelength distances.