Emeritus Faculty, Acad Council, Physics
Wide-field coherent anti-Stokes Raman scattering microscopy with non-phase-matching illumination
2007; 32 (13): 1941-1943
We have developed and tested a wide-field coherent anti-Stokes Raman scattering (CARS) microscopy technique, which provides the simultaneous imaging of an extended illuminated area without scanning. This method is based on the non-phase-matching illumination of a sample and imaging of a CARS signal with a CCD camera using conventional microscope optics. We have identified a set of conditions on the illumination and imaging optics, as well as on sample preparation. Imaging of test objects proved high spatial resolution and chemical selectivity of this technique.
View details for Web of Science ID 000248348300059
View details for PubMedID 17603621
- Experimental investigation of multibunch, multipass beam breakup in the Jefferson Laboratory Free Electron Laser Upgrade Driver PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS 2006; 9 (6)
Transient optical elements: application to near-field microscopy
JOURNAL OF MICROSCOPY-OXFORD
2003; 210: 307-310
We report methods of near-field infrared microscopy with transient optically induced probes. The first technique - a transient aperture (TA) - uses photoinduced reflectivity in semiconductors to generate a relatively large transient mirror (TM) with a small aperture at its centre. We report the optical properties of the TM and TA and experiments performed on near-field imaging with the TA. The second technique is based on solid immersion microscopy, in which high resolution is achieved when light is focused inside a solid with a high refractive index. By creating a transient Fresnel lens on the surface of a semiconductor wafer via photoinduction, we were able to form a solid immersion lens (SIL) for use as a near-field probe. The use of transient probes eliminates the need for mechanical scanning of the lens or sample, and thus provides a much faster scanning rate and the possibility to work with soft and liquid objects.
View details for Web of Science ID 000183307500022
View details for PubMedID 12787104
Resonantlike phenomenon in short-pulse free-electron-laser oscillators with modulated desynchronism
PHYSICAL REVIEW E
2002; 65 (1)
Recently a new method of controlling the pulse length of a short-pulse free-electron laser (FEL) has been developed. By modulating the synchronism between the optical and electron pulses in the FEL cavity, it was found that the output power and the micropulse length of the FEL beam oscillates at the modulation frequency. In this paper, we study theoretically the behavior of the micropulse length, both in the high loss (steady state) regime and the low loss (limit cycle) regime, when a modulated desynchronism is applied. In order to do this, we analyze the dynamics of a short-pulse FEL oscillator. The modulation frequency value plays an important role in the dynamics. We find that there is a resonantlike phenomenon between the externally applied desynchronism modulation and the limit cycle oscillation without modulation of a free-electron laser.
View details for DOI 10.1103/PhysRevE.65.016504
View details for Web of Science ID 000173407500083
View details for PubMedID 11800801
Fast IR imaging with sub-wavelength resolution using a transient near-field probe (Tipless near-field microscopy)
Conference on 3-Dimensional and Multidimensional Microscopy - Image Acquisition and Processing VI
SPIE-INT SOC OPTICAL ENGINEERING. 1999: 31–39
View details for Web of Science ID 000080657900004