Measurement models for time-resolved spectroscopy: a comment

Angle-Resolved Spectroscopy of Parametric Fluorescence

The parametric fluorescence from a nonlinear crystal forms a conical radiation pattern. We measure the angular and spectral distributions of parametric fluorescence in a beta-barium borate crystal pumped by a 405-nm diode laser employing angle-resolved imaging spectroscopy. The experimental angle-resolved spectra and the generation efficiency of parametric down conversion are compared with a plane-wave theoretical analysis. The parametric fluorescence is used as a broadband light source for the calibration of the instrument spectral response function in the wavelength range from 450 to 1000 nm…

Time-resolved Fourier transform intracavity spectroscopy with a Cr2+:ZnSe laser

Intracavity laser absorption spectroscopy (ICLAS) with an evacuated Cr2+: ZnSe laser is performed with a high-resolution time-resolved Fourier transform interferometer with a minimum detectable absorption coefficient equal to 4 10-9 cm-1 Hz-1/2 in the 2.5$μ$m region. This represents the extreme limit presently reached in the infrared by ICLAS with Doppler limited resolution. The broad gain band of the crystal allows a spectral coverage at most equal to 125 nm, wide enough to see entire vibration bands. Weak CO2 bands observed up to now only in the Venus atmosphere are recorded for the first ti…

纠缠光子时间与频率分辨光谱学

Entangled-photon time- and frequency-resolved optical spectroscopy

本文提出利用自发参量下转换产生的纠缠光子对实现时间与频率分辨光谱测量，在单光子水平下分辨光合膜能量传递级联和混合染料寿命，并证明可在接近太阳光照条件下快速完成超快光谱实验。

关联量子去相位法：二维超导体和反铁磁体的对称性解析噪声光谱学

Correlated Quantum Dephasometry: Symmetry-Resolved Noise Spectroscopy of Two-Dimensional Superconductors and Altermagnets

本文提出关联量子去相位法，通过两个自旋量子比特的关联去相位，在纳米尺度和低频下实现材料的对称性解析量子噪声光谱学，用于区分超导能隙的s-, d-和g-波对称性。

Entangled Photons Enabled Time- and Frequency-Resolved Coherent Raman Spectroscopy in Condensed Phase Molecules

We develop an ultrafast frequency-resolved Raman spectroscopy with entangled photons for polyatomic molecules in condensed phases, to probe the electronic and vibrational coherences. Using quantum correlation between the photons, the signal shows the capability of both temporal and spectral resolutions that are not accessible by either classical pulses or the fields without entanglement. We develop a microscopic theory for this Raman spectroscopy, revealing the electronic coherence dynamics which often shows a rapid decay within $\sim$50fs. The heterodyne-detected Raman signal is further devel…

Momentum-resolved spectroscopy of a 1D superfluid using a single atomic impurity

We present a general and non-invasive probing scheme to perform full momentum-resolved spectroscopy of a cold atomic gas loaded into an optical lattice using a single quantum impurity. The protocol relies on weak collisional interactions and subsequent population measurements of the impurity. By tuning a few controllable external parameters the impurity-lattice interaction can be engineered, and using two sets of measurements, performed with the impurity in two different positions, the full dispersion relation of the superfluid phonons can be reliably extracted.