共查询到20条相似文献,搜索用时 265 毫秒
1.
A method for the determination of the noise spectral density in a high-temperature microwave SQUID operating in the hysteresis regime is developed. Under these conditions, the reflection coefficient serves as an output signal. It is shown that if a directional coupler used for extracting the reflected wave is placed as close to the SQUID loop as possible, the magnetometer can be designed as a microwave integrated circuit with a noise flux spectral density SF 1/2 < 10 - 5 F0 /\textHz\text0\text.5 ,\textwhere F\text0 S_\Phi ^{1/2} < 10^{ - 5} \Phi _0 /{\text{Hz}}^{{\text{0}}{\text{.5}}} ,{\text{where }}\Phi _{\text{0}} , is the magnetic flux quantum. 相似文献
2.
In this paper, we consider the global wellposedness of the 3-D incompressible anisotropic Navier-Stokes equations with initial
data in the critical Besov-Sobolev type spaces B{\mathcal{B}} and
B-\frac12,\frac124{\mathcal{B}^{-\frac12,\frac12}_4} (see Definitions 1.1 and 1.2 below). In particular, we proved that there exists a positive constant C such that (ANS
ν
) has a unique global solution with initial data u0 = (u0h, u03){u_0 = (u_0^h, u_0^3)} which satisfies
||u0h||B exp(\fracCn4 ||u03||B4) £ c0n{\|u_0^h\|_{\mathcal{B}} \exp\bigl(\frac{C}{\nu^4} \|u_0^3\|_{\mathcal{B}}^4\bigr) \leq c_0\nu} or
||u0h||B-\frac12,\frac124 exp(\fracCn4 ||u03||B-\frac12,\frac1244) £ c0n{\|u_0^h\|_{\mathcal{B}^{-\frac12,\frac12}_{4}} \exp \bigl(\frac{C}{\nu^4} \|u_0^3\|_{\mathcal{B}^{-\frac12,\frac12}_{4}}^4\bigr)\leq c_0\nu} for some c
0 sufficiently small. To overcome the difficulty that Gronwall’s inequality can not be applied in the framework of Chemin-Lerner
type spaces, [(Lpt)\tilde](B){\widetilde{L^p_t}(\mathcal{B})}, we introduced here sort of weighted Chemin-Lerner type spaces, [(L2t, f)\tilde](B){\widetilde{L^2_{t, f}}(\mathcal{B})} for some apropriate L
1 function f(t). 相似文献
3.
Xue-xiang Xu 《International Journal of Theoretical Physics》2012,51(7):2056-2065
We theoretically study the squeezing effect in a 3-wave mixing process, generated by the operator S3 o exp[m(a1a2-a1fa2f)+n(a1a3-a1fa3f)]S_{3}\equiv \exp[\mu(a_{1}a_{2}-a_{1}^{\dagger}a_{2}^{\dagger})+\nu(a_{1}a_{3}-a_{1}^{\dagger}a_{3}^{\dagger})]. The corresponding 3-mode squeezed vacuum state in Fock space and its uncertainty relation are presented. It turns out that S 3 may exhibit enhanced squeezing. By virtue of integration within an ordered product (IWOP) of operators, we also give the S 3’s normally ordered expansion. Finally, we calculate the Wigner function of 3-mode squeezed vacuum state by using the Weyl ordering invariance under similar transformations. 相似文献
4.
Universality in the Two Matrix Model with a Monomial Quartic and a General Even Polynomial Potential
M. Y. Mo 《Communications in Mathematical Physics》2009,291(3):863-894
In this paper we studied the asymptotic eigenvalue statistics of the 2 matrix model with the probability measure
Z-1nexp(-n(tr(V(M1)+W(M2)-tM1M2)) dM1d M2,Z^{-1}_{n}{\rm exp}\left(-n\left({\rm tr}(V(M_1)+W(M_2)-\tau M_1M_2\right)\right) \, {\rm d}M_1{\rm d} M_2, 相似文献
5.
Benedetto Scoppola 《Journal of statistical physics》2011,143(3):413-419
A class of families of Markov chains defined on the vertices of the n-dimensional hypercube, Ω
n
={0,1}
n
, is studied. The single-step transition probabilities P
n,ij
, with i,j∈Ω
n
, are given by
Pn,ij=\frac(1-a)dij(2-a)nP_{n,ij}=\frac{(1-{\alpha})^{d_{ij}}}{(2-{\alpha})^{n}}, where α∈(0,1) and d
ij
is the Hamming distance between i and j. This corresponds to flip independently each component of the vertex with probability
\frac1-a2-a\frac{1-{\alpha}}{2-{\alpha}}. The m-step transition matrix Pn,ijmP_{n,ij}^{m} is explicitly computed in a close form. The class is proved to exhibit cutoff. A model-independent result about the vanishing
of the first m terms of the expansion in α of Pn,ijmP_{n,ij}^{m} is also proved. 相似文献
6.
J. Stanzel F. Burmeister M. Neeb 《Applied Physics A: Materials Science & Processing》2010,100(1):21-29
We have studied the dynamics of photoexcited tungsten cluster anions Wn-\mathrm{W}_{n}^{-} (n=3,4,…,14) by means of time-resolved two-photon photodetachment spectroscopy. At an excitation energy of h
ν
pump=1.56 eV the photoinduced dynamics is mainly dominated by fast electronic relaxation processes. For the smallest clusters,
i.e., W3-\mathrm{W}_{3}^{-}, W4-\mathrm{W}_{4}^{-}, and W5-\mathrm{W}_{5}^{-}, individual relaxation channels have been identified and resolved on a timescale well below 100 fs. The time constants for
the decay of nascent and secondary electrons have been deduced from a Bloch model. Complete thermalization takes place for
all clusters on a timescale of ∼1 ps. 相似文献
7.
A. H. Hasmani 《International Journal of Theoretical Physics》2009,48(12):3510-3516
In this paper we have assumed charged non-perfect fluid as the material content of the space-time. The expression for the
“mass function-M(r,y,z,t)” is obtained for the general situation and the contributions from the Ricci tensor in the form of material energy density
ρ, pressure anisotropy
[\fracp2+p32-p1][\frac{p_{2}+p_{3}}{2}-p_{1}]
, electromagnetic field energy ℰ and the conformal Weyl tensor, viz. energy density of the free gravitational field ε
(=\frac-3Y24p)(=\frac{-3\Psi_{2}}{4\pi})
are made explicit. This work is an extension of the work obtained earlier by Rao and Hasmani (Math. Today XIIA:71, 1993; New Directions in Relativity and Cosmology, Hadronic Press, Nonantum, 1997) for deriving general dynamical equations for Dingle’s space-times described by this most general orthogonal metric,
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