Widely tunable laser frequency offset lock with 30 GHz range and 5 THz offset

Biesheuvel, J.; Noom, Daniel W. E.; Salumbides, E. J.; Sheridan, K.T.; Ubachs, Wim; Koelemeij, J.C.J.

doi:10.1364/oe.21.014008

Cited by 14 publications

(6 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As described above, this method exploits the finite response time of the PID controller and allows continuous scanning of the frequency of TS1 over the entire mode-hop-free range while keeping it locked to the comb at all times. With this system, continuous sweeps including the discontinuous lock point jumps up to 200 MHz/s are possible, and are similar in ramp rate to the 500 MHz/s demonstrated by Biesheuvel et al [23] when locking to a Fabry-Perot cavity. However, for small continuous sweeps using only the double pass AOM (i.e., without the need to switch the polarity of the error signal) sweep rates of > 3 GHz/s were obtained.…”

supporting

confidence: 59%

See 1 more Smart Citation

Method for independent and continuous tuning of N lasers phase-locked to the same frequency comb

2015

View full text Add to dashboard Cite

We present a method of phase-locking any number of continuous-wave lasers to an optical frequency comb (OFC) that enables independent frequency positioning and control of each laser while still maintaining lock to the OFC. The scheme employs an acousto-optic modulator (AOM) in a double pass configuration added to each laser before its light is compared by optical heterodyne with the comb. The only requirement is that the tuning bandwidth of the double pass AOM setup be larger than half the OFC repetition rate. We demonstrate this scheme and achieve an arbitrary frequency tuning precision, a tuning rate of 200 MHz/s and a readout precision at the 1 kHz level.Modern experiments often require multiple lasers, differing in frequencies by tens of THz and referenced to atomic transitions or stable cavities. For example, optical clocks based on 88 Sr + utilize stabilized coherent sources at 422 nm, 674 nm, 1033 nm and 1092 nm [1,2]. For applications in spectroscopy and related experiments aiming at production of ultracold ground state molecules [3][4][5][6][7], an additional technical difficulty arises from the need to vary the frequency of these stabilized lasers over hundreds to thousands of MHz to characterize a priori unknown molecular levels.Since the development of the self-referenced optical frequency combs (OFC) [8,9] it has been possible to frequency stabilize lasers to the resulting "frequency ruler" by stabilizing the heterodyne beatnote between the laser and the OFC. Using the broadened spectrum of the OFC provides a wide bandwidth for locking, typically corresponding to the 500 -1100 nm range for titanium sapphire based systems [8]. Moreover, non-linear optical processes (including frequency doubling the OFC output when the CW frequency is higher or frequency mixing the OFC output with the CW source itself when the CW frequency is lower) can be used to reliably lock the CW laser even when its frequency has no overlap with the OFC's output spectrum [10,11]. It is worth noting that coherent sources at wavelengths below 500 nm are often based on frequency doubling [13] or frequency sum generation [14], and therefore their stabilization can be done by referencing the seed lasers before nonlinear mixing.The frequency f L of a laser frequency locked to an OFC by stabilizing the beatnote produced in an optical heterodyne with the OFC can be expressed as f L = f CEO + n × f rep ± f beat , where f CEO is the carrier envelope frequency, f rep is the repetition rate of the comb and ±f beat refers to the heterodyne beatnote between the laser frequency and the comb tooth to which the laser is locked.The most straightforward method to simultaneously achieve absolute frequency stability and wide tunability of a CW laser referenced to an OFC relies on the change of f rep [11,15,16], which is multiplied by the mode number n (on the order of 10 6 ) of the comb element to which the laser is referenced. This allows for scanning ranges of many GHz, typically limited by the mode-hop-free tuning range of a laser. This method, ho...

show abstract

supporting

confidence: 59%

“…Our method is similar in spirit to the solution demonstrated by Biesheuvel et al [23]. However, we achieve thousand-fold improvement in precision (1 kHz [24] versus 1 MHz) while maintaining a similar frequency scanning rate (200 MHz/s versus 500 MHz/s).…”

mentioning

confidence: 62%

Method for independent and continuous tuning of N lasers phase-locked to the same frequency comb

2015

View full text Add to dashboard Cite

show abstract

“…We reduce the motional temperature of the HD + ions by storing them together with Be + ions which are Doppler-cooled by a continuous wave (cw) 313 nm laser beam (see [18,23,24] for details). The rf trap is placed inside an ultrahigh vacuum chamber with a background pressure of 1 × 10 −10 mbar.…”

Section: Methodsmentioning

confidence: 99%

High-precision spectroscopy of the HD+ molecule at the 1-p.p.b. level

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…To achieve narrow linewidths and small systematic shifts, we choose to perform spectroscopy on small samples of HD + molecules in a radiofrequency (rf) ion trap. We reduce the motional temperature of the HD + ions by storing them together with Be + ions which are Dopplercooled by a continuous-wave (cw) 313 nm laser beam (see [17,22,23] for details). The rf trap is placed inside an ultra-high vacuum chamber with a background pressure of 1 × 10 −10 mbar.…”

Section: Trapping and Cooling Be + And Hd +mentioning

confidence: 99%

High-precision spectroscopy of the HD+ molecule at the 1-p.p.b. level

Biesheuvel,

Karr,

Hilico

et al. 2016

Preprint

Self Cite

View full text Add to dashboard Cite

Recently we reported a high precision optical frequency measurement of the (v, L): (0,2)→(8,3) vibrational overtone transition in trapped deuterated molecular hydrogen (HD + ) ions at 10 mK temperature. Achieving a resolution of 0.85 parts-per-billion (p.p.b.) we found the experimental value (ν 0 = 383, 407, 177.38(41) MHz) to be in agreement with the value from molecular theory (ν th = 383, 407, 177.150(15) MHz) within 0.6(1.1) p.p.b. [Biesheuvel et al., Nat. Commun. 7, 10385 (2016)]. This enabled an improved test of molecular theory (including QED), new constraints on the size of possible effects due to 'new physics', and the first determination of the proton-electron mass ratio from a molecule. Here, we provide the details of the experimental procedure, spectral analysis, and the assessment of systematic frequency shifts. Our analysis focuses in particular on deviations of the HD + velocity distribution from thermal (Gaussian) distributions under the influence of collisions with fast ions produced during (laser-induced) chemical reactions, as such deviations turn out to significantly shift the hyperfine-less vibrational frequency as inferred from the saturated and Doppler-broadened spectrum, which contains partly unresolved hyperfine structure.

show abstract

Widely tunable laser frequency offset lock with 30 GHz range and 5 THz offset

Cited by 14 publications

References 15 publications

Method for independent and continuous tuning of N lasers phase-locked to the same frequency comb

Method for independent and continuous tuning of N lasers phase-locked to the same frequency comb

High-precision spectroscopy of the HD+ molecule at the 1-p.p.b. level

High-precision spectroscopy of the HD+ molecule at the 1-p.p.b. level

Contact Info

Product

Resources

About