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111.
U.?L.?AndersenEmail author B.?C.?Buchler P.?K.?Lam J.?W.?Wu J.?R.?Gao H.-A.?Bachor 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,27(2):181-191
We report a versatile instrument, based on a monolithic optical parametric amplifier, which reliably generates four different types of squeezed light. We obtained vacuum squeezing, low power amplitude squeezing, phase squeezing and bright amplitude squeezing. We show a complete analysis of this light, including a full quantum state tomography. In addition we demonstrate the direct detection of the squeezed state statistics without the aid of a spectrum analyser. This technique makes the nonclassical properties directly visible and allows complete measurement of the statistical moments of the squeezed quadrature.Received: 10 March 2003, Published online: 26 August 2003PACS:
42.50.Dv Nonclassical states of the electromagnetic field, including entangled photon states; quantum state engineering and measurementsU.L. Andersen: Present address: Institute of Optics, Information and Photonics, Max-Planck Research Group, University of Erlangen-Nuernberg, 91058 Erlangen, Germany. 相似文献
112.
In this paper it is proved that ifp is a prime dividing the order of a groupG with (|G|,p − 1) = 1 andP a Sylowp-subgroup ofG, thenG isp-nilpotent if every subgroup ofP ∩G
N
of orderp is permutable inN
G
(P) and whenp = 2 either every cyclic subgroup ofP ∩G
N
of order 4 is permutable inN
G
(P) orP is quaternion-free. Some applications of this result are given.
The research of the first author is supported by a grant of Shanxi University and a research grant of Shanxi Province, PR
China.
The research of the second author is partially supported by a UGC(HK) grant #2160126 (1999/2000). 相似文献
113.
114.
I. Goidenko I. Tupitsyn G. Plunien 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,45(1):171-177
In this paper, we present a family of coupled higher-order
nonlinear Schr?dinger equation describing the optical soliton pulse
propagating in inhomogeneous optical fiber media. The exact N-soliton
solution and its characteristics of stabilities and novel elastic collision
properties are studied in detail. As an example, we give the relative
numerical evolutions by a soliton control system to discuss the pulses
propagation characteristics. 相似文献
115.
116.
117.
通过观察酸度对模拟转铁蛋白小分子EHPG和HBED紫外差光谱的影响,结合脱铁伴清蛋白与金属离子、阴离子结合的光谱特性,推断脱铁伴清蛋白与金属离子的结合导致金属离子结合位点处酪氨酸酚羟基的去质子化,而与阴离子的结合导致阴离子结合位点处酪氨酸酚羟基的质子化. 相似文献
118.
In this paper, we consider the nonlinear Schrödinger equation with variable coefficients, and by using direct transformation of variables and functions, the explicit chirped gray one- and two-soliton solutions are presented. Based on the exact solutions, we in detail analyze the propagation characteristics of the chirped gray soliton, including the stability against either the deviation from integrable condition or the initial perturbation, and interaction between the chirped gray solitons. The results show that the gray soliton can be compressed by choosing the appropriate initial chirp, and the chirped gray pulses can stably propagate along optical fibers remaining the character of solitons. 相似文献
119.
We report on simultaneous magneto-optical trapping of fermionic ^40K and bosonic 87Rb atoms. This trap is the first step towards quantum degenerate fermi gas ^40K. Laser lights for the two-species magneto-optical trap (MOT) are generated from diode lasers and tapered amplifier. The enriched ^40K dispenser is utilized in the experimental setup. We obtain up to 10^7 -10^8 ^40K and 10^8 -10^9 ^87Rb atoms respectively in the steady-state single-species MOT. 相似文献
120.