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41.
Twenty new optically pumped far-infrared laser transitions have been observed in OCS, including four “maser” transitions of 3.6–8.2 mm wavelength. The operating conditions and assignments of these lines are reported. Rabi splitting of the FIR gain profile caused by the high intensity of the CO2 TEA laser pump is found to be very important for some lines. 相似文献
42.
Cumulant functions are introduced to describe the statistical state of a radiation field. These functions are simply related
to the optical coherence functions but have some interesting features. It is shown that if the cumulant functions of all orders
greater than some numberN
0 vanish then they also vanish for all orders greater than 2. Thermal field is the only field having this property. This property
holds whether the field is described by a classical stochastic process or by a quantum density operator. Further the particular
operator ordering used in defining these cumulant functions for the quantized field affects only the second order cumulant
function. To describe the statistical state of a vector field such as partially polarized or unpolarized radiation, one would
need to introduce cumulant tensors. 相似文献
43.
H. N. Rutt D. N. Travis K. C. Hawkins 《International Journal of Infrared and Millimeter Waves》1984,5(9):1201-1219
An extensive study of the propyne optically pumped laser is presented. 32 new far infrared and 8 new mid infrared outputs are reported, together with pump frequency offset data. Complete assignments of some far infrared transitions and partial assignments of the mid infrared outputs are given. Very strong interactions occur between the mid and far infrared laser transitions. These interactions are of vital importance in obtaining high output energies. 相似文献
44.
David Hawkins 《Journal of Number Theory》1974,6(3):192-200
A proof is presented that the random sieve, a stochastic analogue of the sieve of Eratosthenes, generates sequences of numbers approximating the density of primes. The expected number En[h] of such numbers less than n satisfies and the actual number h(n), on any trial, approximates π(n) in the sense of the weak law of large numbers. Some additional results are given. 相似文献
45.
46.
Atomic spectroscopy is a well‐established, integral part of the physicist's toolbox with an extremely broad range of applications ranging from astronomy to single atom quantum optics. While highly desirable, miniaturization of atomic spectroscopy techniques on the chip scale was hampered by the apparent incompatibility of conventional solid‐state integrated optics and gaseous media. Here, the state of the art of atomic spectroscopy in hollow‐core optical waveguides is reviewed The two main approaches to confining light in low index atomic vapors are described: hollow‐core photonic crystal fiber (HC‐PCF) and planar antiresonant reflecting optical waveguides (ARROWs). Waveguide design, fabrication, and characterization are reviewed along with the current performance as compact atomic spectroscopy devices. The article specifically focuses on the realization of quantum interference effects in alkali atoms which may enable radically new optical devices based on low‐level nonlinear interactions on the single photon level for frequency standards and quantum communication systems. 相似文献
47.
Zhou W Shultz JW Murphy N Hawkins EM Bernad L Good T Moothart L Frackman S Klaubert DH Bulleit RF Wood KV 《Chemical communications (Cambridge, England)》2006,(44):4620-4622
New highly sensitive latent bioluminescent luciferin substrates were designed and synthesized for monitoring mammalian glutathione S-transferase (GST) and Schistosoma japonicum enzyme activities. 相似文献
48.
We show how macroeconomic dynamics can be derived from asymmetric information. As an illustration of the utility of this approach we derive the equilibrium density, non-equilibrium densities and the equation of motion for the response to a demand shock for productivity in a simple economy. Novel consequences of this approach include a natural incorporation of time dependence into macroeconomics and a common information-theoretic basis for economics and other fields seeking to link micro-dynamics and macro-observables. 相似文献
49.
We introduce a method for optical characterization of hollow-core optical waveguides. Radiation pressure exerted by the waveguide modes on dielectric microspheres is used to analyze salient properties such as propagation loss and waveguide mode profiles. These quantities were measured for quasi-single-mode and multimode propagation in on-chip liquid-filled hollow-core antiresonant reflecting optical waveguides. Excellent agreement with analytical and numerical models is found, demonstrating that optically induced particle transport provides a simple, inexpensive, and nondestructive alternative to other characterization methods. 相似文献
50.
We describe, analyze, and demonstrate a high-order spectrally accurate surface integral algorithm for simulating time-harmonic electromagnetic waves scattered by a class of deterministic and stochastic perfectly conducting three-dimensional obstacles. A key feature of our method is spectrally accurate approximation of the tangential surface current using a new set of tangential basis functions. The construction of spectrally accurate tangential basis functions allows a one-third reduction in the number of unknowns required compared with algorithms using non-tangential basis functions. The spectral accuracy of the algorithm leads to discretized systems with substantially fewer unknowns than required by many industrial standard algorithms, which use, for example, the method of moments combined with fast solvers based on the fast multipole method. We demonstrate our algorithm by simulating electromagnetic waves scattered by medium-sized obstacles (diameter up to 50 times the incident wavelength) using a direct solver (in a small parallel cluster computing environment). The ability to use a direct solver is a tremendous advantage for monostatic radar cross section computations, where thousands of linear systems, with one electromagnetic scattering matrix but many right hand sides (induced by many transmitters) must be solved. 相似文献