共查询到20条相似文献,搜索用时 531 毫秒
1.
Kim K Washburn BR Wilpers G Oates CW Hollberg L Newbury NR Diddams SA Nicholson JW Yan MF 《Optics letters》2005,30(8):932-934
A frequency comb is generated with a Cr:forsterite femtosecond laser, spectrally broadened through a highly nonlinear optical fiber to span from 1.0 to 2.2 ,m, and stabilized using the f-to-2f self-referencing technique. The repetition rate and the carrier-envelope offset frequency are stabilized to a hydrogen maser, calibrated by a cesium atomic fountain clock. Simultaneous frequency measurement of a 657-nm cw laser by use of the stabilized frequency combs from this Cr:forsterite system and a Ti:sapphire laser agree at the 10(-13) level. The frequency noise of the comb components is observed at 1064, 1314, and 1550 nm by comparing the measured beat frequencies between cw lasers and the supercontinuum frequency combs. 相似文献
2.
Corwin KL Thomann I Dennis T Fox RW Swann W Curtis EA Oates CW Wilpers G Bartels A Gilbert SL Hollberg L Newbury NR Diddams SA Nicholson JW Yan MF 《Optics letters》2004,29(4):397-399
A frequency comb is generated with a chromium-doped forsterite femtosecond laser, spectrally broadened in a dispersion-shifted highly nonlinear fiber, and stabilized. The resultant evenly spaced comb of frequencies ranges from 1.1 to beyond 1.8 microm. The frequency comb was referenced simultaneously to the National Institute of Standards and Technology's optical frequency standard based on neutral calcium and to a hydrogen maser that is calibrated by a cesium atomic fountain clock. With this comb we measured two frequency references in the telecommunications band: one half of the frequency of the d/f crossover transition in 87Rb at 780 nm, and the methane v2 + 2v3 R(8) line at 1315 nm. 相似文献
3.
Hong FL Onae A Jiang J Guo R Inaba H Minoshima K Schibli TR Matsumoto H Nakagawa K 《Optics letters》2003,28(23):2324-2326
The absolute frequency of an acetylene-stabilized laser at 1542 nm is measured at its second harmonic (771 nm) by use of a femtosecond optical comb based on a mode-locked Ti:sapphire laser. Frequency stability and reproducibility of the acetylene-stabilized laser are evaluated by the femtosecond comb with a H maser as a frequency reference. The absolute frequency of a laser diode stabilized on the P(16) transition of 13C2H2 is determined to be 194 369 569 383.6(1.3) kHz. The acetylene-stabilized laser serves as an important optical frequency standard for telecommunication applications. 相似文献
4.
W.-Y. Cheng T.-H. Wu S.-W. Huang S.-Y. Lin C.-M. Wu 《Applied physics. B, Lasers and optics》2008,92(1):13-18
We demonstrated a novel scheme for scanning the absolute frequencies of a femtosecond Kerr-lens mode-locked Ti:sapphire laser
with the repetition rate unaffected, where the carrier-envelop phase of the pulse was controlled by slightly shifting pump
beam and the repetition rate was phase locked to a stable radio-frequency oscillator. Since it was the first time to stabilize
the frequency of a mode-locked laser by referring directly to the frequency of cesium two-photon-transition (TPT) stabilized
diode laser, we evaluated the frequency instability and the frequency accuracy that showed the characteristic of being a comb
laser. The feature of the comb laser in this report will be significant for multi-photon spectroscopy where the frequency
difference between comb lines plays a key role.
PACS 06.30.+v; 42.60.By 相似文献
5.
A repetition-rate-stabilized frequency comb ranging from the violet to the mid-infrared (0.4-2.4 microm) is obtained by phase locking a femtosecond Ti:sapphire laser and a synchronously pumped optical parametric oscillator to a common supercontinuum reference. The locking results have bandwidths lower than 3 kHz. By changing the locking frequencies, different relative and absolute offsets of the constituent frequency combs are achievable. 相似文献
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7.
Niering M Holzwarth R Reichert J Pokasov P Udem T Weitz M Hansch TW Lemonde P Santarelli G Abgrall M Laurent P Salomon C Clairon A 《Physical review letters》2000,84(24):5496-5499
We report on an absolute frequency measurement of the hydrogen 1S-2S two-photon transition in a cold atomic beam with an accuracy of 1.8 parts in 10(14). Our experimental result of 2 466 061 413 187 103(46) Hz has been obtained by phase coherent comparison of the hydrogen transition frequency with an atomic cesium fountain clock. Both frequencies are linked with a comb of laser frequencies emitted by a mode locked laser. 相似文献
8.
Carrier-envelope offset phase control: A novel concept for absolute optical frequency measurement and ultrashort pulse generation 总被引:5,自引:0,他引:5
H.R. Telle G. Steinmeyer A.E. Dunlop J. Stenger D.H. Sutter U. Keller 《Applied physics. B, Lasers and optics》1999,69(4):327-332
The shortest pulses periodically emitted directly from a mode-locked Ti:sapphire laser are approaching the two-optical-cycle
range. In this region, the phase of the optical carrier with respect to the pulse envelope becomes important in nonlinear
optical processes such as high-harmonic generation. Because there are no locking mechanisms between envelope and carrier inside
a laser, their relative phase offset experiences random fluctuations. Here, we propose several novel methods to measure and
to stabilize this carrier-envelope offset (CEO) phase with sub-femtosecond uncertainty. The stabilization methods are an important
prerequisite for attosecond pulse generation schemes. Short and highly periodic pulses of a two-cycle laser correspond to
an extremely wide frequency comb of equally spaced lines, which can be used for absolute frequency measurements. Using the
proposed phase-measurement methods, it will be possible to phase-coherently link any unknown optical frequency within the
comb spectrum to a primary microwave standard. Experimental studies using a sub-6-fs Ti:sapphire laser suggesting the feasibility
of carrier-envelope phase control are presented.
Received: 19 August 1999 / Published online: 8 September 1999 相似文献
9.
We link the output spectra of a Ti:sapphire and a Cr:forsterite femtosecond laser phase coherently to form a continuous frequency comb with a wavelength coverage of 0.57-1.45 microm at power levels of 1 nW to 40 microW per frequency mode. To achieve this, the laser repetition rates and the carrier-envelope offset frequencies are phase locked to each other. The coherence time between the individual components of the two combs is 40 micros. The timing jitter between the lasers is 20 fs. The combined frequency comb is self-referenced for access to its overall offset frequency. We report the first demonstration to our knowledge of an extremely broadband and continuous, high-powered and phase-coherent frequency comb from two femtosecond lasers with different gain media. 相似文献
10.
The absolute frequencies of rubidium 5S-7S two-photon transitions at 760 nm are measured to an accuracy of 20 kHz with an optical frequency comb based on a mode-locked femtosecond Ti:sapphire laser. The rubidium 5S-7S two-photon transitions are potential candidates for frequency standards and serve as important optical frequency standards for telecommunication applications. The accuracy of the hyperfine constant of the 7S1/2 state is improved by a factor of 5 in comparison with previous results. 相似文献
11.
Harro G. Andresen 《Zeitschrift für Physik A Hadrons and Nuclei》1968,210(2):113-141
Hydrogen maser frequency shifts, caused by the multiple quantum transition nonlinearities of a resonant multiple frequency excitation of the atomic hydrogen four level ground state system have been investigated. The oscillation characteristics of hydrogen maser operation with simultaneously excited, low frequencyΔm F =±1 transitions between theF=1 states of the atomic hydrogen ground state have been analysed theoretically and explicit formulas for hydrogen maser frequency shifts and amplitude response have been derived for arbitrary maser oscillation amplitude and a small signal approximation for theΔm F =±1 “Zeeman” transitions. The comparison with experimentally observed hydrogen maser frequency shifts was specialized to small magnetic fields, for which the difference between the resonance frequencies of the two low frequency,Δm F =±1 Zeeman transitions is small compared to the linewidth. Special emphasis was placed on the evaluation of frequency pulling effects for a Zeeman transition excitation at off-resonance conditions. For this case the theoretical formulation of frequency pulling effects becomes insensitive against simplifying assumptions about the radiation damping phenomena and a particular good agreement between experiment and theory can therefore be expected. Experimental conditions have been specified, for which the uncertainty of hydrogen maser frequency due to Zeeman transition induced frequency shifts does not restrict the present frequency stability of a hydrogen maser frequency standard. 相似文献
12.
13.
We have measured the frequency of the 6s(2)S(1/2)(2)-5d D(3/2)(2) electric-quadrupole transition of (171)(Yb) (+) with a relative uncertainty of 1x10(-14) , nu(Yb)=688358 979309312Hz +/-6Hz . We used a femtosecond frequency comb generator to phase-coherently link the optical frequency derived from a single trapped ion to a cesium-fountain-controlled hydrogen maser. This measurement is one of the most accurate measurements of optical frequencies ever reported, and it represents a contribution to the development of optical clocks based on a (171)Yb(+)-ion standard. 相似文献
14.
Schibli TR Minoshima K Hong EL Inaba H Bitou Y Onae A Matsumoto H 《Optics letters》2005,30(17):2323-2325
We present an arbitrary optical single-frequency generator based on a femtosecond optical frequency comb. The functions of this device are comparable to those of a radio-frequency synthesizer. However, this device operates at hundreds of terahertz. The absolute frequency accuracy of this synthesizer is approximately 1 kHz at a 282 THz carrier frequency. The stability is approximately 2 x 10(-14) at 100 s, and the tuning speed exceeds 30 GHz/s. This source demonstrates the integration of a phase-locked optical comb into a versatile and easy-to-use system for the generation of tunable, absolute optical frequencies. By using downconversion, one could generate tunable terahertz frequencies that are phase locked to a microwave reference, such as a Cs atomic clock, and high-precision interferometry could benefit greatly from the stability and accuracy of this widely tunable source. 相似文献
15.
An optical clockwork is created with a compact 1-GHz repetition-rate laser and three nonlinear crystals. The broadband continuum output of the laser covers sufficient bandwidth to provide direct access to its carrier-envelope offset frequency without the use of a microstructure fiber. We phase lock the femtosecond comb to a Ca optical standard and monitor the stability of the repetition rate, f(r) , at 1 GHz. We demonstrate that the short-term stability of the microwave output of the optical clock is at least as good as that of a high-performance hydrogen maser. 相似文献
16.
Precise determination of characteristic laser frequencies by an Er-doped fiber optical frequency comb
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Shiying Cao 《中国物理 B》2022,31(7):74207-074207
Femtosecond optical frequency combs correlate the microwave and optical frequencies accurately and coherently. Therefore, any optical frequency in visible to near-infrared region can be directly traced to a microwave frequency. As a result, the length unit "meter" is directly related to the time unit "second". This paper validates the capability of the national wavelength standards based on a home-made Er-doped fiber femtosecond optical frequency comb to measure the laser frequencies ranging from visible to near-infrared region. Optical frequency conversion in the femtosecond optical frequency comb is achieved by combining spectral broadening in a highly nonlinear fiber with a single-point frequency-doubling scheme. The signal-to-noise ratio of the beat notes between the femtosecond optical frequency comb and the lasers at 633, 698, 729, 780, 1064, and 1542 nm is better than 30 dB. The frequency instability of the above lasers is evaluated by using a hydrogen clock signal with a instability of better than 1×10-13 at 1-s averaging time. The measurement is further validated by measuring the absolute optical frequency of an iodine-stabilized 532-nm laser and an acetylene-stabilized 1542-nm laser. The results are within the uncertainty range of the international recommended values. Our results demonstrate the accurate optical frequency measurement of lasers at different frequencies using the femtosecond optical frequency comb, which is not only important for the precise and accurate traceability and calibration of the laser frequencies, but also provides technical support for establishing the national wavelength standards based on the femtosecond optical frequency comb. 相似文献
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18.
利用光纤飞秒光频梳和外腔可调谐半导体激光器, 建立了一套双频He-Ne激光器频率测量系统. 选用铷钟作为系统的频率基准, 通过将外腔半导体激光锁定至光频梳使得其频率溯源至铷钟, 再利用外腔可调谐半导体激光与双频He-Ne激光器输出的正交偏振激光拍频, 同时测量两路正交偏振激光频率. 将可调谐半导体激光器锁定至光频梳第1894449个梳齿, 其绝对频率为473612190000.0±2.7 kHz, 相对不确定度为5.7×10-12. 对商品双频He-Ne激光器进行频率测量实验, 双频He-Ne激光器水平方向偏振激光频率均值为473612229934 kHz, 竖直方向偏振激光频率均值为473612232111 kHz, 平均时间为1024 s的相对Allan标准差为5.2×10-11, 频差均值为2.177 MHz, 标准偏差为2 kHz. 相似文献
19.
We have demonstrated a new technique that provides massively parallel comb spectroscopy sensitive specifically to ions through the combination of cavity-enhanced direct frequency comb spectroscopy with velocity-modulation spectroscopy. Using this novel system, we have measured electronic transitions of HfF? and achieved a fractional absorption sensitivity of 3×10?? recorded over 1500 simultaneous channels spanning 150 cm?1 around 800 nm with an absolute frequency accuracy of 30 MHz (0.001 cm?1). A fully sampled spectrum consisting of interleaved measurements is acquired in 30 min. 相似文献