Ultrafast Fourier transform

We have developed ultrahigh-precision coherent control based on this WPI, in which we have succeeded in visualizing and controlling the ultrafast evolution of a WP interference in a molecule with precisions on the picometer spatial and attosec-ond (as) temporal scales [37-39], This is the cutting edge of coherent control. We have utilized this ultrahigh-precision coherent control to develop a molecular computer that executes ultrafast Fourier transform with molecular wave functions in 145 fs [40,41], More recently, we have extended the target of our coherent control to wave functions delocalized in a bulk solid [42,43], In this account, we will describe these developments of our experimental toolbox and the outlook toward the coherent control around the quantum-classical boundary. 

Figure 7.11 Schematic of the ultrafast Fourier transform. The common transform matrices could be operated for any arbitrary inputs and outputs, respectively, by the indicated hardware. Reproduced with permission from Ref. [41]. Copyright 2010 by the American Physical Society.

Fig. 4 Coherent oscillations observed by Fup and co-workers after ultrafast photodissociation of group 6 metal carbonyls. The Fourier transform of the oscillatory part shows a peak at 96cm which compares to 98cm found for equatorial L-M-L bending in Jahn-Teller moat using semi-classical direct dynamics [43] (reused from [70] with permission)...

Among approaches in vibrational spectroscopy are differential and time-resolved IR and Raman spectroscopy, coherent anti-Stokes Raman scattering (CARS), Fourier transform infrared spectroscopy (FT-IR) multidimensional IR and RR spectroscopy, two-dimensional infrared echo and Raman echo [56], and ultrafast time-resolved spontaneous and coherent Raman spectroscopy the structure and dynamics of photogenerated transient spedes [50, 57]. 

In the case of albendazole (36) (Scheme 27) ultrafast MAS, solid-state NMR spectroscopy, together with powder X-ray diffraction, thermal analysis, and Fourier transform IR spectroscopy were performed on polycrystalline samples of two solids in order to fuUy characterize and distinguish the two forms 36a and 36b. High-resolution 2D H, and together with 2D H/ H single quantum/single quantum, H/ H single quantum/double quantum, and chemical shift correlation solid-state NMR experi-... 

In 1958, spinning of a NaCl crystal at a 90° angle with the magnetic field is achieved [6]. Later, MAS was implemented at a 7000 Hz rate and Fourier transformed NMR spectra of Teflon and CaF2 were recorded in 7 mm rotors [7]. In 1997, 2.5 mm rotors (for MAS rates up to 33-35 kHz) became commercially available by Bruker. Samoson and the group in Tallinn realized numerous technology-driven developments MAS rates of 50 kHz with rotors of 2 mm diameter were demonstrated in 1999 in their laboratory [8]. Nowadays, very fast (>30 kHz) and ultrafast (>40—50 kHz) MAS probes are now commercially available (see Fig. 3.2 for a summary), with the commercial release by JEOL of a 110 kHz MAS probe with a 0.75 mm rotor announced in 2012 at the 53rd ENC Conference. 

Tseng, C.-H., Sandor, P., Kotur, M., Weinacht, T.C., Matsika, S. Two-dimensional Fourier transform spectroscopy of adenine and uracil using shaped ultrafast laser pulses in the deep UV. J. Phys. Chem. A 116, 2654-2661 (2012)... 

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