摘要:
Infrared generation is disclosed. A first laser field having a first frequency associated with a first interband transition is generated. A second laser field having a second frequency associated with a second interband transition is generated. The generation of the first laser field occurs substantially simultaneously with the generation of the second laser field. A third laser field is generated from the first laser field and the second laser field. The third laser field has a third frequency associated with an intersubband transition. The third frequency is substantially equivalent to a difference between the second frequency and the first frequency.
摘要:
Method and apparatus for increasing the index of refraction, n, by several orders of magnitude. Pumping and probing radiation excite the various atomic levels of a material, and establish coherence between such levels. Index of refraction can thereby be increased while, concomitantly, absorbence of the material is minimized.
摘要:
A laser pulse from an ultrashort pulse laser (USPL) is fired into the atmosphere. The USPL pulse is configured to generate a plasma filament at a predefined target in the atmosphere, in which free, or “seed,” electrons are generated by multi-photon or tunneling ionization of the air molecules in the filament. A second pulse is fired into the atmosphere to form a heater beam that impinges on the plasma filament and thermalizes the seed electrons within the plasma filament, leading to the collisional excitation of the electrons in the filament. The excited electrons collisionally excite various electronic and vibrational states of the air molecules in the filament, causing population inversions and lasing, e.g., exciting the C3Πu→B3Πg(v=0→0) transition of the N2 in the atmosphere to cause lasing at 337 nm.
摘要:
A method and system provide coherent anti-Stokes Raman spectroscopy. In an embodiment, the system includes a detection system for measuring coherent anti-Stokes Raman signals of a sample. The system includes a first light pulse and a second light pulse. The first light pulse and the second light pulse are operable to initiate coherent vibration in the sample. The system also includes a third light pulse. The third light pulse is a probe pulse that is operable to produce scattered radiation from the sample. In addition, the system includes a spectral filter. The spectral filter shapes the probe pulse. The system further includes a detector to record the spectrum of the scattered radiation.
摘要:
According to one embodiment, detecting radiation includes receiving a first laser drive field at a cell comprising a medium having a number of states. The first laser drive field has a frequency approximately equivalent to a transition frequency between a first state and a second state. A second laser drive field having a frequency approximately equivalent to a transition frequency between the first state and a third state, and an infrared field having a frequency approximately equivalent to a transition frequency between the third state and a fourth state are received. The medium has a transition between the second state and the third state substantially forbidden to support optimal coherence on the transition between the second state and the third state. The infrared field is upconverted to generate a detectable field having a frequency approximately equivalent to a transition frequency between the second state and the fourth state.
摘要:
According to one embodiment of the present invention, identifying a molecule of a sample includes illuminating the sample with a preparation light beam, where the preparation light beam can initiate a substantially maximized coherence of a target molecule to yield a molecular signature corresponding to the target molecule. The sample is illuminated with a probe light beam, where the probe light beam can scatter radiation from the sample. Radiation scattered from the sample is detected, and whether the radiation exhibits the molecular signature is determined. The target molecule is identified in accordance with the determination of whether the radiation exhibits the molecular signature.
摘要:
A time release bolus comprises a tubular member and an end cap secured to each other. The tubular member contains an inner bag which is adapted to receive and contain a nutrient or medicament substance. A capsule is provided in the tubular member, and upon fracture thereof, applies pressure to the inner bag. The end cap includes a plug which fits into an open end of the tubular member and a top portion. A passage is provided which leads from the tubular member to the exterior, such that nutrient or medicament can flow from the inside of the tubular member to the outside of the time release bolus. The bolus further includes in the end cap a mesh in the flow path of the substance, the mesh further restricting and controlling the amount of substance which may pass from the bolus to the exterior. Wings are provided on the end cap which are movable between a first retracted position where insertion per os of the bolus takes plus, and a second extended position adopted in the rumen to prevent regurgitation of the bolus.
摘要:
Indwelling sustained release reservoirs for dispensing bloat-controlling agents to the rumens of grazing livestock. A plurality of osmotic dispensing devices with varying release patterns generate by bioerodible deposits on their osmotic membranes. The devices are linked together by bioerodible means so that they may be released and pass from the rumen when their contents are exhausted.
摘要:
Method and device for correlating the spontaneous emission of photons into laser fields. Atoms of a common lasing medium of multiple laser fields are excited into a coherent superposition of upper levels. When photons are emitted into the laser fields, these emissions are coherent or correlated. The method and correlated emission laser of the invention utilize this correlation to quench the spontaneous emission noise inherent in active laser systems.
摘要:
An apparatus for generating stimulated x-ray emission. In accordance with the invention there is provided a means for producing a gas jet target capable of population inversion. Also provided is a means for generating an ion beam and a means for scanning the ion beam longitudinally along the gas jet so as to cause emission therefrom. The scanning speed is established as being substantially equal to the wavefront velocity of the emission; i.e., the speed of light. A hydrogen gas jet overcomes problems encountered using a thin hydrogen-rich foil. The hydrogen jet is not destroyed by the ion beam and the problem of making a suitable thin foil is eliminated. Also, by employing an appropriate beam density, the Doppler width is reduced as compared to the foil so that gain improvement can be achieved.