Hébert Nicolas Bourbeau, Michaud-Belleau Vincent, Anstie James D, Deschênes Jean-Daniel, Luiten Andre N, Genest Jérôme
Opt Express. 2015 Oct 19;23(21):27806-18. doi: 10.1364/OE.23.027806.
We present an original instrument designed to accomplish high-speed spectroscopy of individual optical lines based on a frequency comb generated by pseudo-random phase modulation of a continuous-wave (CW) laser. This approach delivers efficient usage of the laser power as well as independent control over the spectral point spacing, bandwidth and central wavelength of the comb. The comb is mixed with a local oscillator generated from the same CW laser frequency-shifted by an acousto-optic modulator, enabling a self-heterodyne detection scheme. The current configuration offers a calibrated spectrum every 1.12 µs. We demonstrate the capabilities of the spectrometer by producing averaged, as well as time-resolved, spectra of the D1 transition of cesium with a 9.8-MHz point spacing, a 50-kHz resolution and a span of more than 3 GHz. The spectra obtained after 1 ms of averaging are fitted with complex Voigt profiles that return parameters in good agreement with expected values.
我们展示了一种基于连续波（CW）激光的伪随机相位调制产生的频率梳，用于完成单个光谱线高速光谱分析的原创仪器。这种方法实现了激光功率的高效利用，以及对频率梳的谱点间距、带宽和中心波长的独立控制。该频率梳与由声光调制器频移的同一连续波激光产生的本地振荡器混频，实现了自外差检测方案。当前配置每1.12微秒提供一次校准光谱。我们通过产生平均光谱以及时间分辨光谱来展示该光谱仪的能力，这些光谱是铯D1跃迁的光谱，谱点间距为9.8兆赫兹，分辨率为50千赫兹，跨度超过3吉赫兹。平均1毫秒后获得的光谱用复Voigt轮廓拟合，得到的参数与预期值高度吻合。
