共查询到20条相似文献,搜索用时 15 毫秒
1.
根据角速度传感的基本原理,搭建了以高Q光学微球腔为核心敏感部件的角速度传感实验测试系统。实验中通过调制、解调技术得到了光学微球腔的谐振曲线及其相对应的解调曲线,并采用PID反馈控制电路实现了微球腔谐振点的实时跟踪锁定,谐振点锁定精度约为10 kHz。通过对系统提供低、高2组不同的旋转角速度进行实验测试,并对数据进行处理分析,得到系统输出信号幅度的变化趋势与测试转台提供的旋转角速度变化情况相对应的结果。初步验证了高Q光学微球腔的角速度传感效应,为后续深入研究高Q光学微谐振腔角速度传感器件奠定了基础。 相似文献
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We investigate the degradation of the Q factor of a fundamental whispering-gallery mode of a microsphere resonator when a fiber tip is placed in the evanescent field of the mode. With a tip diameter of 80 nm it is possible to maintain a Q factor exceeding 10(8), even when the tip is as close as 10 nm to the sphere surface. This result demonstrates the possibility of using such a tip as a "nanotool" to actively place a single nanoparticle in a single high- Q mode with great precision to achieve well-controlled coupling. 相似文献
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A. Mazzei S. Gtzinger L.de S. Menezes V. Sandoghdar O. Benson 《Optics Communications》2005,250(4-6):428-433
In this paper, we demonstrate a novel method for optimizing the in- and out-coupling of light confined in the fundamental high-Q whispering-gallery mode of a microsphere resonator via an external prism coupler. The technique relies on the use of a near-field probe to map the modes of the resonator and to obtain topographical information at the same time. We demonstrate the feasibility and efficiency of this technique by applying it to a sphere with a radius of 59 μm. 相似文献
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Optical Review - A nanograting microring resonator is proposed for achieving concentric mode field profiles as the effect of guided-mode resonance. Based on a numerical simulation of the 2D... 相似文献
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An optical ring resonator with asymmetric three-layered dielectrics is shown to have an anomalously highQ-factor compared with the conventional symmetric three-layered ring resonator by several orders of magnitude for suitably chosen parameters. A new leaky mode which can propagate on the asymmetric structure is found having an extremely small attenuation loss near the cut-off frequency of the guided mode, but which does not exist in the symmetric structure. Optimum values of the normalized frequency for a single-mode operation to suppress the undesired leaky modes are discussed. It is also shown that the size of the ring resonator using the asymmetric structure can be reduced considerably from that of the ordinary symmetric resonator. 相似文献
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LIU YiMin 《中国科学:物理学 力学 天文学(英文版)》2013,56(11):2138-2142
We propose a potentially practical scheme for efcient generation of entanglement with two nitrogen-vacancy centers(NVC)coupled to a whispering-gallery mode cavity.By virtue of the virtual-photon-excitation,the entanglement with two separate NVC can be produced in a deterministic way.The required operations are very close to the capabilities of current experimental techniques.The efects of decoherence induced by the cavity decay and the atomic spontaneous decay are also investigated. 相似文献
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We study the quantum dynamics of N coherently driven two-level atoms coupled to an optical resonator. In the strong coupling regime the cavity field generated by atomic scattering interferes destructively with the pump on the atoms. This suppresses atomic excitation and even for strong driving fields prevents atomic saturation, while the stationary intracavity field amplitude is almost independent of the atom number. The magnitude of the interference effect depends on the detuning between laser and cavity field and on the relative atomic positions and is strongest for a wavelength spaced lattice of atoms placed at the antinodes of the cavity mode. In this case three dimensional intensity minima are created in the vicinity of each atom. In this regime spontaneous emission is suppressed and the dominant loss channel is cavity decay. Even for a cavity linewidth larger than the atomic natural width, one regains strong interference through the cooperative action of a sufficiently large number of atoms. These results give a new key to understand recent experiments on collective cavity cooling and may allow to implement fast tailored atom-atom interactions as well as nonperturbative particle detection with very small energy transfer.Received: 18 May 2004, Published online: 19 October 2004PACS:
32.80.Pj Optical cooling of atoms; trapping - 42.50.Pq Cavity quantum electrodynamics; micromasers - 42.50.Fx Cooperative phenomena in quantum optical systems 相似文献
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We optically characterize nanolayer (<150 nm) formation in situ on a silica microsphere in an aqueous environment by simultaneously following the shifts of whispering-gallery modes at two wavelengths. This approach was inspired by layer perturbation theory, which indicates that these two measurements can be used to determine independently both the thickness and the optical dielectric constant. The theory is verified for extreme cases and used to characterize a biophysically relevant hydrogel nanolayer with an extremely small excess refractive index of 0.0012. 相似文献
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Pigtailing the high-Q microsphere cavity: a simple fiber coupler for optical whispering-gallery modes 总被引:5,自引:0,他引:5
We demonstrate a simple method for efficient coupling of standard single-mode optical fibers to a high- Q optical microsphere cavity. Phase-matched excitation of whispering-gallery modes is provided by an angle-polished fiber tip in which the core-guided wave undergoes total internal reflection. In the experimental setup, which included a microsphere with both an input and an output coupler, the total fiber-to-fiber transmission at resonance reached 23% (total insertion loss, 6.3 dB), with loaded quality factor Q>/=3x10(7) and unloaded Q approximately 1.2x10(8) at 1550 nm. A simple pigtailing method for microspheres permits their wider use in fiber optics and photonics devices. 相似文献
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Nonaxisymmetric fused-silica microspheres were fabricated by using only one microsphere by virtue of short pulses of a CO2 laser. Highly directional emission from whispering-gallery modes (WGMs) was studied through direct free-space evanescent excitation. The observed quality factors of WGMs are high, up to 2x10(7), despite this deformation. We show that WGMs in slightly deformed microspheres possibly play an important role in cavity quantum electrodynamics research. 相似文献
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We show that a glass microsphere resonator can be used as a wavelength-selective mirror in fiber lasers. Due to their high quality factor (Q approximately 10(8)), microsphere resonators possess a narrow reflection bandwidth. This feature enables construction of single-frequency fiber lasers even when the laser cavity is long. Nonlinear effects (such as stimulated Raman lasing) were also observed in our setup at relatively low pump powers. 相似文献
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We propose and demonstrate an active Q-switched fiber laser using a high-Q microsphere resonator as the Q-switching element. The laser cavity consists of an Er-doped fiber as the gain medium, a glass microsphere reflector (coupled through a fiber taper) at one end of the cavity, and a fiber Bragg grating reflector at the other end. The reflectivity of the microsphere is modulated by changing the gap between the microsphere and the fiber taper. Active Q switching is realized by oscillating the microsphere in and out of contact with the taper. Using this novel technique, we have obtained giant pulses (maximum peak power approximately 102 W, duration approximately 160 ns) at a low pump-power threshold (approximately 3 mW). 相似文献
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M. V. Zhuravlev 《Radiophysics and Quantum Electronics》2009,52(2):157-164
We study the threshold conditions of the parametric excitation of temperature oscillations using pulsed microwave pumping
in three-mode regime for high-Q ferroelectric cryogenic resonators made of SrTiO3 and KTaO3. Comparative analysis is performed for the threshold power of the excitation of temperature oscillations and the threshold
power of the ponderomotive parametric excitation of acoustic oscillations in the resonator. It is shown that in three-mode
regime, temperature oscillations can develop under a rather moderate pump power of about 0.1–8 μW, depending on the combination of interacting temperature and electromagnetic modes. The calculated low threshold powers
allow one to apply resonators in practice as high-sensitivity infrared sensors, resonant bolometers, and parametric amplifiers.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 52, No. 2, pp. 172–180, February 2009. 相似文献
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N. S. Ginzburg A. K. Kaminsky S. V. Kuzikov É. A. Perel’shteĭn N. Yu. Peskov S. N. Sedykh A. P. Sergeev A. S. Sergeev 《Technical Physics》2006,51(7):887-893
The operation of a pulsed free-electron maser with a Bragg resonator and resonant termination is simulated in terms of nonstationary equations. It is shown that the termination partially loses its reflection properties and accumulates microwave energy when the eigenfrequency of the terminating resonator coincides with the frequency of the maser transition radiation. The difference between these frequencies produces considerable reflections and in the long run quenches masing. The masing stability depends on the lag of the reflected signal and channel losses. 相似文献
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A. Colligiani I. Longo M. Martinelli M. Lucchesi L. Pardi 《Applied magnetic resonance》1995,9(4):567-579
The behaviour of a disc-shaped dielectric resonator made of sintered alumina and working in the Whispering Gallery Mode (WGM) has been studied in the frequency interval from about 8 up to about 26 GHz. Many equidistant resonances have been detected in this frequency interval each of which being characterized by a satisfactoryQ-value due to the very good self-confinement of the microwave field which is typical of WGM propagation. Particular care has been devoted to the optimization of the coupling between the resonating disc and the microwave source. Examples of ESR spectra obtained on each of the detected resonances are reported which show the variation of the lineshape with the increase of the frequency. The obtained results allow one to foresee that the same dielectric disc can be used for ESR spectroscopy also at frequencies much higher than those up to now exploited. 相似文献
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Microwave photonic filter with a continuously tunable central frequency using an SOI high-Q microdisk resonator
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Utilizing a high-Q microdisk resonator(MDR) on a single silicon-on-insulator(SOI) chip, a compact microwave photonic filter(MPF) with a continuously tunable central frequency is proposed and experimentally demonstrated. Assisted by the optical single side-band(OSSB) modulation, the optical frequency response of the MDR is mapped to the microwave frequency response to form an MPF with a continuously tunable central frequency and a narrow 3-dB bandwidth. In the experiment, using an MDR with a compact size of 20×20 μm2and a high Q factor of 1.07×105, we obtain a compact MPF with a high rejection ratio of about 40 dB, a 3-dB bandwidth of about 2 GHz, and a frequency tuning range larger than12 GHz. Our approach may allow the implementation of very compact, low-cost, low-consumption, and integrated notch MPF in a silicon chip. 相似文献