共查询到20条相似文献,搜索用时 31 毫秒
1.
T. Kawazoe M. Ohtsu S. Aso Y. Sawado Y. Hosoda K. Yoshizawa K. Akahane N. Yamamoto M. Naruse 《Applied physics. B, Lasers and optics》2011,104(3):537-546
We present a detailed study of the dynamics of light in passive nonlinear resonators with shallow and deep intracavity periodic
modulation of the refractive index in both longitudinal and transverse directions of the resonator. We investigate solutions
localized in the transverse direction (so-called Bloch cavity solitons) by means of envelope equations for underlying linear
Bloch modes and solving Maxwell’s equations directly. Using a round-trip model for forward and backward propagating waves
we review different types of Bloch cavity solitons supported by both focusing (at normal diffraction) and defocussing (at
anomalous diffraction) nonlinearities in a cavity with a weak-contrast modulation of the refractive index. Moreover, we identify
Bloch cavity solitons in a Kerr-nonlinear all-photonic crystal resonator solving Maxwell’s equations directly. In order to
analyze the properties of Bloch cavity solitons and to obtain analytical access we develop a modified mean-field model and
prove its validity. In particular, we demonstrate a substantial narrowing of Bloch cavity solitons near the zero-diffraction
regime. Adjusting the quality factor and resonance frequencies of the resonator optimal Bloch cavity solitons in terms of
width and pump energy are identified. 相似文献
2.
We show numerically that bright and dark cavity solitons can be obtained in bidirectional class A ring lasers only if the phase invariance of the electromagnetic field is broken. The phase invariance symmetry is responsible for the existence of phase waves, which generate long-range interactions destroying the property of independence among otherwise localized structures. We improved the usual model describing such types of lasers, and we prove that it leads to genuine cavity solitons. 相似文献
3.
M. Bache F. Prati G. Tissoni R. Kheradmand L.A. Lugiato I. Protsenko M. Brambilla 《Applied physics. B, Lasers and optics》2005,81(7):913-920
We study theoretically a broad-area vertical cavity surface emitting laser (VCSEL) with a saturable absorber. We show numerically
the presence of cavity solitons in the system: they exist as solitary structures formed through a modulationally unstable
homogeneous lasing state that coexists with a background with zero intensity. Such a peculiar scenario endows the solitons
with unique properties compared to cavity solitons in most previously studied optical systems. In particular, these solitons
do not as such rely on a proper phase of the addressing pulses to be either created or deleted. We show that exciting and
deleting the solitons depend crucially on whether a threshold in the soliton peak has been reached. 相似文献
4.
L. Columbo F. Prati M. Brambilla T. Maggipinto 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2010,59(1):115-120
We consider a broad area heterostructured semiconductor laser with an integrated saturable absorber in a monolithic configuration.
We extend beyond the single-longitudinal mode approximation a model already used to predict transversely localized structures
or cavity solitons (CSs) in a shorter device and we numerically demonstrate the existence of self-pulsing transverse localized
structures.
Like CSs, these structures can simultaneously coexist in different transverse locations. 相似文献
5.
Vilaseca R Torrent MC García-Ojalvo J Brambilla M San Miguel M 《Physical review letters》2001,87(8):083902
We show that broad-area cascade lasers with no absorbing intracavity elements support the spontaneous formation of two-dimensional bright localized structures in a dark background. These cavity solitons consist of islands of two-photon emission embedded in a background of single-photon emission. We discuss the mechanisms through which these structures are formed and interact, along with their properties and stability. 相似文献
6.
We describe what we believe to be novel types of discrete cavity solitons in nonlinear waveguide arrays that are driven by an external holding beam. We demonstrate that a holding beam with a definite inclination drives the system in a subdiffractive regime and allows the formation of stable discrete cavity solitons. We predict the existence of both bright and dark moving midband discrete cavity solitons for an identical set of system parameters for both focusing and defocusing Kerr nonlinearities. 相似文献
7.
8.
L. Colombo L. Gil J. R. Tredicce 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2010,60(2):435-233
We show that class A bi-directional ring lasers do not support the existence of cavity solitons even under the presence of
diffusion for the electromagnetic field. However there is a parameter range where an infinite number of patterns coexist.
Such coexistence yields optical localized structures whose dynamical properties are in many ways similar to those of cavity
solitons. In particular they allow writing and erasing under the action of very specific perturbations. 相似文献
9.
We report on experimental observation of localized structures in two mutually coupled broad-area semiconductor resonators, one of which acts as a saturable absorber. These structures coexist with a dark homogeneous background and they have the same properties as cavity solitons without requiring the presence of a driving beam into the system. They can be switched individually on and off by means of a local addressing beam. 相似文献
10.
T. Elsass K. Gauthron G. Beaudoin I. Sagnes R. Kuszelewicz S. Barbay 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2010,59(1):91-96
We present recent experimental results on the control and dynamics
of cavity solitons in a monolithic, vertical cavity surface emitting
laser with saturable absorber. On one hand, the fast and independent
manipulation of two laser cavity solitons is achieved and a flip-flop
operation is demonstrated with a single control-beam. On the other
hand, a pulsing localized structure is presented and we demonstrate
the control of a pulsing multispot structure that we can switch-on
and off. These results are promising in view of the obtainment of
a pulsed and monolithic cavity soliton laser. 相似文献
11.
《中国光学快报(英文版)》2016,(12)
Temporal cavity solitons(CSs) have excellent properties that can sustain their shape in a temporal profile and with a broadband, smooth-frequency spectrum. We propose a method for controllable frequency line spacing soliton formation in a microresonator using two continuous-wave(CW) pumps with multi-free-spectral-range(FSR) spacing. The method we propose has better control over the amount and location of the solitons traveling in the cavity compared to the tuning pump method. We also find that by introducing a second pump with frequency N FSR from the first pump, solitons with N FSR comb spacing can be generated. 相似文献
12.
《Physics Reports》2002,370(2):63-235
We present an overview of nonlinear phenomena related to optical quadratic solitons—intrinsically multi-component localized states of light, which can exist in media without inversion symmetry at the molecular level. Starting with presentation of a few derivation schemes of basic equations describing three-wave parametric wave mixing in diffractive and/or dispersive quadratic media, we discuss their continuous wave solutions and modulational instability phenomena, and then move to the classification and stability analysis of the parametric solitary waves. Not limiting ourselves to the simplest spatial and temporal quadratic solitons we also overview results related to the spatio-temporal solitons (light bullets), higher order quadratic solitons, solitons due to competing nonlinearities, dark solitons, gap solitons, cavity solitons and vortices. Special attention is paid to a comprehensive discussion of the recent experimental demonstrations of the parametric solitons including their interactions and switching. We also discuss connections of quadratic solitons with other types of solitons in optics and their interdisciplinary significance. 相似文献
13.
We predict a novel type of cavity solitons, Bloch cavity solitons, existing in nonlinear resonators with the refractive index modulated in both longitudinal and transverse directions and for both focusing (at normal diffraction) and defocusing (at anomalous diffraction) nonlinearities. We develop a modified mean-field theory and analyze the properties of these novel cavity solitons demonstrating, in particular, their substantial narrowing in the zero-diffraction regime. 相似文献
14.
I.M. Perrini S. Barbay T. Maggipinto M. Brambilla R. Kuszelewicz 《Applied physics. B, Lasers and optics》2005,81(7):905-912
We have developed a model that describes the optical response of a semiconductor quantum dot medium in a cavity in order to
investigate pattern and cavity solitons formation. This model, beyond the inclusion of the inhomogeneous broadening of the
quantum dot linewidth [1] (due the fluctuations of the quantum dot sizes that arise in self-organized growth), takes into
account more complex phenomena such as the thermal escape and capture as well as Auger scattering mechanisms coupling the
quantum dot itself with the wetting layer, and carrier diffusion in the unconfined directions of the wetting layer. We have
studied the conditions for the onset of bistability and modulational instability and characterize the patterns formed at the
bifurcated solutions. New features brought by these terms and indications on the most favourable regimes for cavity solitons
formation are discussed.
PACS 42.65.Sf; 42.65.An; 78.67.Hc 相似文献
15.
Biondini G 《Physical review letters》2007,99(6):064103
We study soliton solutions of the Kadomtsev-Petviashvili II equation (-4u(t)+6uu(x)+3u(xxx))(x)+u(yy)=0 in terms of the amplitudes and directions of the interacting solitons. In particular, we classify elastic N-soliton solutions, namely, solutions for which the number, directions, and amplitudes of the N asymptotic line solitons as y-->infinity coincide with those of the N asymptotic line solitons as y-->-infinity. We also show that the (2N-1)!! types of solutions are uniquely characterized in terms of the individual soliton parameters, and we calculate the soliton position shifts arising from the interactions. 相似文献
16.
17.
18.
Zhi-Yuan Sun Yi-Tian Gao Xin Yu Ying Liu 《International Journal of Theoretical Physics》2011,50(9):2776-2789
We investigate compression of the bright bound solitons in the Bose-Einstein condensates (BECs) by exponentially increasing the absolute value of the atomic scattering length. Similarity transformation and Hirota bilinear method are used to symbolically solve the one-dimensional nonlinear Schrödinger equation with the time-dependent coefficients. We present types of the bright bound solitons in compression through manipulating their initial coherence. Results show that the improved quantity of the atomic density peaks can be observed before the collapse of the solitons when their coherence is increased. Furthermore, we discuss how those compressed bound solitons are influenced by the adjacent solitons. The bound structures in our study are illustrated to exist with the parameters within the current experimental capacity (the spatial and temporal ranges of the bound solitons are less than 56 μm and 50 ms in our investigation), which suggests a future observation in the BECs experiments. 相似文献
19.
Cavity solitons in semiconductor amplifiers were, from the beginning of their study and observation, obtained either spontaneously or in a controlled manner by local coherent excitation. We describe two experiments that demonstrate coherent and, we believe for the first time, incoherent writing and erasure of cavity solitons in an optically pumped vertical-cavity semiconductor amplifier by short optical pulses. 相似文献
20.
George Wainblat 《Physica D: Nonlinear Phenomena》2009,238(14):1143-1151
We report the results of systematic numerical analysis of collisions between two and three stable dissipative solitons in the two-dimensional (2D) complex Ginzburg-Landau equation (CGLE) with the cubic-quintic (CQ) combination of gain and loss terms. The equation may be realized as a model of a laser cavity which includes the spatial diffraction, together with the anomalous group-velocity dispersion (GVD) and spectral filtering acting in the temporal direction. Collisions between solitons are possible due to the Galilean invariance along the spatial axis. Outcomes of the collisions are identified by varying the GVD coefficient, β, and the collision “velocity” (actually, it is the spatial slope of the soliton’s trajectory). At small velocities, two or three in-phase solitons merge into a single standing one. At larger velocities, both in-phase soliton pairs and pairs of solitons with opposite signs suffer a transition into a delocalized chaotic state. At still larger velocities, all collisions become quasi-elastic. A new outcome is revealed by collisions between slow solitons with opposite signs: they self-trap into persistent wobbling dipoles, which are found in two modifications — horizontal at smaller β, and vertical if β is larger (the horizontal ones resemble “zigzag” bound states of two solitons known in the 1D CGL equation of the CQ type). Collisions between solitons with a finite mismatch between their trajectories are studied too. 相似文献