共查询到20条相似文献,搜索用时 15 毫秒
1.
D.?Aumiler T.?Ban N.?Vuji?i? S.?Vdovi? H.?Skenderovi? G.?Pichler 《Applied physics. B, Lasers and optics》2009,97(3):553-560
We introduce a method for determination of the absolute frequencies of comb lines within an optical frequency comb spectrum.
The method utilizes the experimental and theoretical approach of the velocity-selective optical pumping of the atomic ground
state hyperfine levels induced by resonant pulse-train excitation. The information on the laser pulse repetition frequency
and carrier–envelope offset are physically mapped onto the 87Rb ground state hyperfine level population velocity distributions. Theoretical spectra are calculated using an iterative analytic
solution of the optical Bloch equations describing the resonant pulse-train excitation of four-level 87Rb atoms. They are employed to fit the measured spectra and obtain the parameters of the frequency comb, thus providing a
practical algorithm which can be used in real-time measurements. 相似文献
2.
Li Zhongyang Yang Lulu Wang Kaiwu Shi Chenxu Chen Zhiliang Xu Juan Bing Pibin Zhu Anfu Xu Degang Zhong Kai Yao Jianquan 《Optical Review》2023,30(4):411-417
Optical Review - A novel scheme that generates terahertz optical frequency comb (THz OFC) based on optimized cascaded difference frequency generation (OCDFG) with an aperiodically poled lithium... 相似文献
3.
We achieve a quantum-noise-limited absorption sensitivity of 1.7×10(-12) cm(-1) per spectral element at 400 s of acquisition time with cavity-enhanced frequency comb spectroscopy, the highest demonstrated for a comb-based technique. The system comprises a frequency comb locked to a high-finesse cavity and a fast-scanning Fourier transform spectrometer with an ultralow-noise autobalancing detector. Spectra with a signal-to-noise ratio above 1000 and a resolution of 380 MHz are acquired within a few seconds. The measured absorption line shapes are in excellent agreement with theoretical predictions. 相似文献
4.
S. Uetake K. Matsubara H. Ito K. Hayasaka M. Hosokawa 《Applied physics. B, Lasers and optics》2009,97(2):413-419
We report results of frequency stability measurements of an extended cavity diode laser (ECDL) whose frequency is stabilized
by a non-evacuated scanning transfer cavity. The transfer cavity is locked to a commercial frequency stabilized helium–neon
laser. Frequency stability is measured by use of an optical frequency comb. The environmental perturbations (variations of
temperature, air pressure, and humidity) are also simultaneously measured. The observed frequency drift of the ECDL is well
explained by environmental perturbations. An atmospheric pressure variation, which is difficult to control with a non-evacuated
cavity, is mainly affected to the frequency stability. Thus we put the cavity into a simple O-ring sealed (non-evacuated)
tube. With this simple O-ring sealed tube, the frequency drift is reduced by a factor of 3, and the Allan variance reaches
a value of 2.4×10−10, corresponds to the frequency stability of 83 kHz, at the average time of 3000 s. Since the actual frequency drift is well
estimated by simultaneous measurement of the ambient temperature, pressure, and humidity, a feed-forward compensation of frequency
drifts is also feasible in order to achieve a higher frequency stability with a simple non-evacuated transfer cavity. 相似文献
5.
Fortier TM Coq YL Stalnaker JE Ortega D Diddams SA Oates CW Hollberg L 《Physical review letters》2006,97(16):163905
We have performed sub-Doppler spectroscopy on the narrow intercombination line of cold calcium atoms using the amplified output of a femtosecond laser frequency comb. Injection locking of a 657-nm diode laser with a femtosecond comb allows for two regimes of amplification, one in which many lines of the comb are amplified, and one where a single line is predominantly amplified. The output of the laser in both regimes was used to perform kilohertz-level spectroscopy. This experiment demonstrates the potential for high-resolution absolute-frequency spectroscopy over the entire spectrum of the frequency comb output using a single high-finesse optical reference cavity. 相似文献
6.
7.
《中国物理 B》2015,(6)
The high precision two-photon excitation measurements for 5S1/2(F87g = 2) to 5D5/2(Fe = 4 to 1) ofRb are performed by using an optical frequency comb.The two counter-propagating femtosecond pulses(5S1/2→5P3/2at 780 nm,and 5P3/2→5D5/2at 776 nm) act on87 Rb vapor,and the Doppler broadened background signal is effectively eliminated.The temperature and power dependences of the two-photon spectrum are studied in this paper. 相似文献
8.
Using a 10.5-GHz resonant electro-optic modulator placed inside a resonant optical cavity, we generated an optical frequency comb with a span wider than 3 THz. The optical resonator consists of three mirrors, with the output coupler being a thin Fabry-Perot cavity with a free spectral range of 2 THz and a finesse of 400. Tuning this filter cavity onto resonance with a particular high-order sideband permits efficient output coupling of the desired sideband power from the comb generator, while keeping all other sidebands inside for continued comb generation. This spectrally pure output light was then heterodyne detected by another laser with a frequency offset of the order of 1 THz. 相似文献
9.
This paper presents a novel circuit for wideband optical comb generation which will be useful in DWDM applications. The injection-locked feedback loop broadens the bandwidth of the optical comb. The injection-locked laser diodes perform amplification, bandpass filtering as well as laser RIN suppression. Several hundred GHz bandwidth optical comb can be generated by this circuit within a reasonable power envelope. 相似文献
10.
We evaluated the accuracy of an optical frequency comb in optical fibers by measuring the frequency shift after a sideband from an electro-optic modulator had passed through the fiber. We found that a frequency drift of a few hertz was due largely to a variation in the ambient temperature that corresponded to an increase in the square root of the Allan variance to 0.66 Hz. 相似文献
11.
We compared two methods for measuring large optical frequency differences: an optical frequency comb generator, which creates a large number of sidebands from a single-mode laser through electro-optic modulation, and an optical frequency interval divider chain, which divides a frequency gap successively by two until it becomes accessible to a radio-frequency counter. By locking two diode lasers to two modulation sidebands of a comb generator, ~1 THz apart, and measuring this interval with a chain of four phase-locked interval dividers, we demonstrate for the first time to our knowledge the accuracy of both techniques within an experimental limit of 6.8 x 10(-15). 相似文献
12.
We propose an ultrafast optical arbitrary waveform synthesizing/analyzing technique demonstrated with 2 Tbit/s waveforms. An ultrafast waveform was generated by manipulating the amplitude and phase of a 400?GHz optical frequency comb using a newly developed colorless optical synthesizer. The 400?GHz optical frequency comb was generated from a 25?GHz optical frequency comb using a colorless arrayed waveguide grating. This waveform was then analyzed on the frequency axis using a custom heterodyne-detection technique based on the dual-heterodyne mixing method. The phase and amplitude spectra can be observed in parallel using another optical frequency comb as a reference combined with an arrayed waveguide grating. This optical system, named the ultrafast optical frequency comb synthesizer and analyzer, can synthesize and analyze an arbitrary waveform in the THz frequency region. 相似文献
13.
We report on a mid-IR frequency comb source of unprecedented tunability covering the entire 3-10 μm molecular fingerprint region. The system is based on difference frequency generation in a GaSe crystal pumped by a 151 MHz Yb:fiber frequency comb. The process was seeded with Raman-shifted solitons generated in a highly nonlinear suspended-core fiber with the same source. Average powers up to 1.5 mW were achieved at the 4.7 μm wavelength. 相似文献
14.
A scheme to generate ultra-flat and stable optical frequency comb (OFC) based on multi-wavelength optical seed source and polarization-modulator-based complementary frequency shifter (PCFS) has been proposed and demonstrated. The OFC generation scheme includes two stages: 5-carrier light source is generated by utilizing a polarization modulator at the first stage, and the light source is then used as the seed light in the PCFS at the second stage. Compared with the previous flat OFC generator based on a recirculation frequency shifter, the proposed scheme can greatly reduce the recirculation times, and such a property makes the accumulated noise of the system enormously decrease. In order to achieve the frequency comb with the best flatness, the optical amplifier gain, filter stop-band attenuation and modulator drive voltage are optimized. Experiment simulations show that high-quality OFC with hundreds of frequency lines and power fluctuation within 2 dB can be achieved without direct-current bias control and wavelength-selective-switch. 相似文献
15.
Multi-wavelength pulse generation using flattop optical frequency comb and arrayed waveguide grating
A scheme of multi-wavelength pulse generator using optical frequency comb and arrayed waveguide grating (AWG) is proposed and experimentally demonstrated. A flattop optical frequency comb is shaped into multiple narrowband Gaussian spectra by using an AWG which contains a number of Gaussian channels, and then multi-wavelength optical pulses are achieved. In the experiment, six wavelength pulses with full width at half-maximum (FWHM) of 14.6 ps at 10 GHz are obtained, and two wavelength-interleaved pulse trains at 20 GHz and four wavelength-interleaved pulse trains at 40 GHz are demonstrated by using the multi-wavelength optical pulses. This scheme has flexibility because the pulse width, the repetition rate, and time-interval can be readily controlled. 相似文献
16.
We theoretically prove that a conventional Mach-Zehnder modulator can generate an optical frequency comb with excellent spectral flatness. The modulator is asymmetrically dual driven by large amplitude sinusoidal signals with different amplitudes. The driving condition to obtain spectral flatness is analytically derived and optimized, yielding a simple formula. This formula also predicts the conversion efficiency and bandwidth of the generated frequency comb. 相似文献
17.
A diode laser spectrometer at 634nm and absolute frequency measurements using optical frequency comb 下载免费PDF全文
This paper reports that two identical external-cavity-diode-laser
(ECDL) based spectrometers are constructed at 634 nm referencing on
the hyperfine B-X transition R(80)8-4 of 127I2. The lasers
are stabilized on the Doppler-free absorption signals using the
third-harmonic detection technique. The instability of the
stabilized laser is measured to be 2.8×10-12 (after
1000 s) by counting the beat note between the two lasers. The
absolute optical frequency of the transition is, for the first time,
determined to be 472851936189.5 kHz by using an optical frequency
comb referenced on the microwave caesium atomic clock. The
uncertainty of the measurement is less than 4.9 kHz. 相似文献
18.
采用光学频率梳的高精度绝对距离测量技术在航空航天、科学研究和工业生产等领域都发挥着重要作用.提出一种利用光学频率梳技术,通过检测光强实现绝对距离测量的新方法,研究了光学频率梳发出脉冲的时间相干性,分析了光强与被测距离之间的关系、干涉条纹峰值点位置与被测距离之间的关系.建立了基于Michelson干涉原理的测距系统,通过测量光强信息得到被测距离.以高精度纳米位移平台的位移量作为长度基准进行了绝对测距实验,在每个被测距离点都重复进行了10次实验,将10次实验测得的光强值取平均后用于距离的计算.实验结果表明,该方法可以实现绝对距离测量,在10μm测量范围内,最大误差为47 nm.因此,该方法可以应用于大尺寸高精度的绝对距离测量. 相似文献
19.
A long-term frequency-stabilized erbium-fiber-laser-based optical frequency comb with an intra-cavity electro-optic modulator 下载免费PDF全文
《中国物理 B》2015,(6)
We demonstrate an optical frequency comb based on an erbium-doped-fiber femtosecond laser with the nonlinear polarization evolution scheme.The repetition rate of the laser is about 209 MHz.By controlling an intra-cavity electrooptic modulator and a piezo-transducer,the repetition rate can be stabilized with a high-bandwidth servo in a frequency range of 3 k Hz,enabling long-term repetition rate phase-locking.The in-loop frequency stability of repetition rate is about1.6×10-13 in an integration time of 1 s,limited by the measurement system;and it is inversely proportional to integration time in the short term.Furthermore,using a common path f –2 f interferometer,the carrier envelope offset frequency of the comb is obtained with a signal-to-noise ratio of 40 d B in a 3-MHz resolution bandwidth.Stabilized carrier envelope offset frequency exhibits a deviation of 0.6 m Hz in an integration time of 1 s. 相似文献
20.
One-way quantum computing allows any quantum algorithm to be implemented easily using just measurements. The difficult part is creating the universal resource, a cluster state, on which the measurements are made. We propose a scalable method that uses a single, multimode optical parametric oscillator (OPO). The method is very efficient and generates a continuous-variable cluster state, universal for quantum computation, with quantum information encoded in the quadratures of the optical frequency comb of the OPO. 相似文献