共查询到20条相似文献,搜索用时 46 毫秒
1.
Asiri Nanayakkara 《理论物理通讯》2012,(5):645-648
Asymptotic energy expansion method is extended for polynomial potentials having rational powers. New types of recurrence relations are derived for the potentials of the form V(x)=x2n/m+b1xn1/m1+b2xn2/m2 +··· + bNxnN/mN where n,m,n1,m1,...,nN,mN are positive integers while coefficients bk∈ C. As in the case of even degree polynomial potentials with integer powers, all the integrals in the expansion can be evaluated analytically in terms of Γ functions. With the help of two examples, we demonstrate the usefulness of these expansions in getting analytic insight into the quantum systems having rational power polynomial potentials. 相似文献
2.
FAN Hong-Yi 《理论物理通讯》2006,45(5):845-848
For the superposition field
a1†+a2†
of two light modes we introduce an appropriate diagonal
P-representation which is constructed on the common eigenvectors |z,x〉of
(X1-X2) and
a1+a2,
where Xi=(ai+
ai†)/√(2),
[ai,ai†] =δij. It is remarkable that |z,x〉make up a new quantum mechanical representation. 相似文献
3.
Fokas system is the simplest (2+1)-dimensional extension of the nonlinear Schrödinger equation (Eq. (2), Inverse Problems 10 (1994) L19-L22). By using the bilinear transformation method, general rational solutions for the Fokas system are given explicitly in terms of two order-N determinants τn (n = 0, 1) whose elements mi,j(n) (n = 0, 1; 1 ≤ i, j ≤ N) are involved with order-ni and order-nj derivatives. When N = 1, three kinds of rational solution, i.e., fundamental lump and fundamental rogue wave (RW) with n1 = 1, and higher-order rational solution with n1 ≥ 2, are illustrated by explicit formulas from τn (n = 0, 1) and pictures. The fundamental RW is a line RW possessing a line profile on (x, y)-plane, which arises from a constant background with at t << 0 and then disappears into the constant background gradually at t >> 0. The fundamental lump is a traveling wave, which can preserve its profile during the propagation on (x, y)-plane. When N ≥ 2 and n1 = n2 = ··· = nN = 1, several specific multi-rational solutions are given graphically. 相似文献
4.
测定了酸性水溶液中甘氨酸、丝氨酸和天冬氨酸稀土络合物(Ln=La、Pr、Nd、Eu、Tb、Dy、Ho、Er、Tm和Yb)的13C诱导位移。对位移试剂的分析指出,三种氨基酸通过α-羧基以双齿形式配位于稀土,配位键长为0.23nm~0.25nm,天冬氨酸的γ-羧基也是配位基团。由本文与文献中已报道的各种氨基酸稀土络合物的13C诱导位移的系统分析表明,配体13C超精细偶合常数A值和结构因子G值有如下规律:(1)│A(C0)│<│A(Cα)│;A(C0)为正,A(Cα)为负;(2)│G(C0)│>│G(Cα)│;配体碳核的G均为负值。 相似文献
5.
In this paper,the variable separation approach is used to obtain localized coherent structures of the (2 1)-dimensional generalized Davey-Stewarson equations:iqt 1/2(qxx=qyy) (R S)q=0,Rx=-σ/2|q|y^2,Sy=-σ/2|q|2/x.Applying a special Baecklund transformation and introducing arbitrary functions of the seed solutions.and abundance of the localized structures of this model is derived,By selceting the arbitrary functions appropriately,some special types of localized excitations such as dromions,dromion lattice,breathers,and instantons are constructed. 相似文献
6.
三元黄铜矿结构(也称类金刚石结构)半导体是一类具有热电转换潜力的新型热电材料. 本次工作中采用电负性更小的Mn元素替换CuInTe2黄铜矿结构半导体中的Cu元素, 设计制备贫Cu化合物Cu1-xInMnxTe2. 研究表明, 当Mn含量较低时, Mn优先占位在In 位置产生受主缺陷MnIn-. 因此随着Mn含量的增大, 载流子浓度和电导率均得到改善. 但当Mn含量进一步增大后, Mn可同时占位在In位置和Cu位置, 除产生受主缺陷MnIn-外, 还能产生施主缺陷MnCu+. 由于两类极性相反的缺陷之间的湮灭现象, 使得缺陷浓度及载流子浓度开始降低, 晶格结构畸变有变小趋势, 因此在高温下晶格热导率仅略有提高. 研究结果表明, 在某一特定的Mn含量(x=0.05)时, 材料具有最优的热电性能(ZT=0.84@810.0 K), 这一性能约是未掺杂CuInTe2的2倍. 相似文献
7.
We first introduce the universal associated Legendre polynomials, which are occurred in studying the non-central fields such as the single ring-shaped potential and then present definite integrals IA±(a, τ)=∫-1+1xa[Pl'm'(x)]2/(1±x)τdx, a=0, 1, 2, 3, 4, 5, 6, τ=1, 2, 3, IB(b, σ)=∫-1+1xb[Pl'm'(x)]2/(1- x2)σdx, b=0, 2, 4, 6, 8, σ=1, 2, 3, and IC±(c, κ)=∫-1+1xc[Pl'm'(x)]2/[(1-x2)κ(1±x)]dx, c=0, 1, 2, 3, 4, 5, 6, 7, 8, κ=1, 2. The superindices “±” in IA±(a, τ) and IC±(c, κ) correspond to those of the factor (1±x) involved in weight functions. The formulas obtained in this work and also those for integer quantum numbers l' and m' are very useful and unavailable in classic handbooks. 相似文献
8.
The cross sections of
Ω+Ω→(ΩΩ)Jπ=0++X
are studied by using an effective Hamiltonian method. The results
are σΩ+Ω→(ΩΩ)0++γ=0.03~0.16×10-29 cm2 for
pΩ=100~400 MeV, and
the cross sections of η production are about 10-28 cm2 for
pΩ > 880 MeV. 相似文献
9.
A. Martínez-de la Cruz F.E. Longoria Rodríguez 《Journal of Physics and Chemistry of Solids》2008,69(4):830-834
Electrochemical lithium insertion into (PO2)4(WO3)2m, where m=9 and 10, has allowed the determination of several phases Lix(PO2)4(WO3)2m between 3.4 and 0.01 V vs Li+/Li0. After the first cycle the electrochemical system was unable to maintain the high specific capacity of the cells (540 Ah/kg) due to irreversible processes. Nevertheless at high voltage values, above 1.4 V vs Li+/Li0, the lithium insertion proceeded through a reversible mechanism. By means of X-ray diffraction experiments we have detected the nature of different phases Lix(PO2)4(WO3)2m formed and we have established a correlation with the reversible/irreversible processes detected during the electrochemical insertion. 相似文献
10.
We study the υμ and υγ decays in the early epoch of the universe. If mυγ > 2me, there would be a CP asymmetry between υγ→e++e-+υe and υγ→e++ e-+ υe. The resultant CP non-invariance is a function of temperature and density and can reach l0-7 for a reasonable temperature range, but it is noticed that if mυγ > 2υμ~200 MeV, the CP non-invariance can be much larger. 相似文献
11.
CHAO Kuang-Ta 《理论物理通讯》1984,3(2):211-220
The rate for the conversion of the gluon into a color octet quark pair which subsequently forms a multiquark state with another quark pair or a gluon is discussed. The static potential in a [(QQ)8(qq)8,1] state where Q=c,b and q=u, d is studied in the MIT bag model. It is shown that the repulsive Coulomb force between Q and Q is dominant at small QQ separations, which would significantly suppress the QQ wave function at the origin. For the charm quark (Q=c) the ratio of |Ψ(O)|2 for the ordinary (QQ)1 to that for the(QQ)8 in the [(QQ)8(qq)8,1] state is estinated to be 2-5. Therefore the assumption |Ψ8(O)|2=|Ψ1(O)|2 would lead to an overestimation for the rate of g*→QQ and it is necessary to take the suppression effect of the repulsive Coulomb force into consideration. 相似文献
12.
CHEN Feng-Zhi 《理论物理通讯》2001,36(3):291-294
We study an SU(3)L×U(1)X electroweak model. By requiring
M2Z1-M2W/cos2θW to be less than experimental value we obtain a lower bound on Z' boson mass, MZ'
>600 GeV. The relation between
MZ' and MU
(MV) then gives a
lower bound on MU (MV):MU (MV)>490 GeV. From the constraint sin2
θW(MZ')<0.3, the upper bounds on MZ' and
MU (MV) are computed to be MZ'<5.8×104 TeV and
MU (MV)<4.6×104 TeV. We estimate further the KL-KS
mass difference due to Z' exchange and try to use the result to
obtain stronger lower bounds. On cosmological grounds we find that
MN<390 eV for Tf=2.3 GeV and
MN<740 eV for Tf=300 GeV. 相似文献
13.
By the concept of effective boson numbers, systematics of E21+E41+E61+, R=E21+/E41, B(E2, 01+→21+) and Q0 for even-even nuclei with A≥70 are presented. New features of energy spectra are noticed and an intuitive understanding is given. 相似文献
14.
SONG Tong-Qiang 《理论物理通讯》2005,43(6):1107-1110
The four-particle EPR entangled state | p,χ2,χ3,χ4〉is constructed. The corresponding quantum mechanical operator with respect to the classical transformation p→eλ1p, χ2→
eλ2χ2, χ3→eλ3χ3, and χ4→eλ4χ4 in the state |p,χ2 ,χ3 ,χ4〉is investigated, and the four-mode realization of the
SU(1,1) Lie algebra as well as the corresponding squeezing operators are
presented. 相似文献
15.
Yuhua Wang Yunkui Sun Jiachi Zhang Zhipeng Ci Zhiya Zhang Lei Wang 《Physica B: Condensed Matter》2008,403(12):2071-2075
The Y0.85Bi0.1Eu0.05V1−yMyO4 (M=Nb, P) as new near-ultraviolet excited phosphors were synthesized and their luminescence properties under 365 nm excitation were investigated in detail. It indicated that by doping small amount of P5+ into V5+ sites, the excitation intensity of charge transfer (CT) band of Bi–O (330–400 nm) was greatly improved. By substituting Nb5+ for V5+, both the CT bands of Bi–O and Eu–O (240–320 nm) were significantly enhanced. As a result, the emission intensity of Y0.85Bi0.1Eu0.05V1−yMyO4 (M=Nb, P) could be improved about 90% by doping 5 mol% P5+ and 110% by doping 5 mol% Nb5+. Comparing with the commercial Y2O2S:Eu3+ phosphors, the Y0.85Bi0.1Eu0.05V0.95M0.05O4 (M=Nb, P) phosphors exhibited excellent color purity and much higher brightness. The results showed that these Y0.85Bi0.1Eu0.05V1−yMyO4 (M=Nb, P) phosphors could be considered as promising red phosphors for application in LED. 相似文献
16.
Tamara A. Leskova Ingve Simonsen Alexei A. Maradudin 《Waves in Random and Complex Media》2002,12(3):307-319
We study the statistical properties of the scattering matrix S(q|k) for the problem of the scattering of light of frequency ω from a randomly rough one-dimensional surface, defined by the equation x3=ζ(x1), where the surface profile function ζ(x1) constitutes a zero-mean, stationary, Gaussian random process. This is done by studying the effects of S(q|k) on the angular intensity correlation function C(q,k|q',k')=〈I(q|k)I(q'|k')〉-〈I(q|k)〉〈I(q'|k')〉, where the intensity I(q|k) is defined in terms of S(q|k) by I(q|k)=L-11(ω/c)|S(q|k)|2, with L1 the length of the x1 axis covered by the random surface. We focus our attention on the C(1) and C(10) correlation functions, which are the contributions to C(q,k|q',k') proportional to δ(q-k-q'+k') and δ(q-k+q'-k'), respectively. The existence of both of these correlation functions is consistent with the amplitude of the scattered field obeying complex Gaussian statistics in the limit of a long surface and in the presence of weak surface roughness. We show that the deviation of the statistics of the scattering matrix from complex circular Gaussian statistics and the C(10) correlation function are determined by exactly the same statistical moment of S(q|k). As the random surface becomes rougher, the amplitude of the scattered field no longer obeys complex Gaussian statistics but obeys complex circular Gaussian statistics instead. In this case the C(10) correlation function should therefore vanish. This result is confirmed by numerical simulation calculations. 相似文献
17.
We consider a system of substances Aj reacting according to the scheme: Ai + Aj +Ak Ai+j+k, which is described by the generalized Smoluchovski equation. We discuss the existence of global solutions of this kinetic equation, and show that the total number of monomers may decrease as the result of the formation of infinite clustere (gelation) for some special coagulation kernels. We also solve the case R(i, j, κ) = sisjsκ with sκ = Ak + B explicitly, and find that the gelation indeed occurs at tc = (6A + B)/6A2(A + B)2. 相似文献
18.
根据描述电子声子相互作用的Fr?hlich哈密顿量,推导出了金属螺旋型碳纳米管(n1,n2)的Peierls相变温度的一般表达式,并利用该式计算了(6,3)的Peierls相变温度.结果表明金属螺旋型碳纳米管在远离室温下都不会发生Peierls相变,仍然保持其金属性
关键词:
螺旋型碳纳米管
电子声子相互作用
Peierls相变 相似文献
19.
提出了一种严格求解任意自旋-s算子幺正演化矩阵的方法,该方法不同于群论的方法和直接计算的方法,是一种间接的算法.方法的核心是利用两个系统表示的等价性:即自旋-s算子Hamiltonian量Hs=Sx与Heisenberg XX开链带相互作用Jn=n(N-n)的Hamiltonian量的等价性,由于存在这种等价性,自旋-s算子幺正演化矩阵的计算可通过Heisenberg XX开链中态的演化来实现.采用该方法计算了s=3/2,s=2和s=5/2时对应的幺正演化矩阵.由于初始态|sm〉在算子e-itSx下的演化实质上相当于对态|sm〉进行一个绕x轴转角为β=t的转动,演化矩阵元dsm'm(t)=〈sm′|e-itSx|sm〉就是转动后的态e-itSx|sm〉在|sm′〉态上的投影值,所以在t=π时刻的演化矩阵刚好对应Heisenberg XX开链上量子态的理想传输.
关键词:
s算子')" href="#">自旋-s算子
幺正演化矩阵
量子态传输 相似文献
20.
XU Dian-Yan 《理论物理通讯》2005,43(3):445-448
The total quantum statistical entropy of Reissner-Nordstrom
black holes in Dirac field case is evaluated in this article.
The space-time of the black holes is divided into three regions:
region 1 (r>ro), region 2 ( ro > r > ri), and
region 3 (ri >r>0), where
ro is the
radius of the outer event horizon, and ri is the radius of the
inner event horizon. The total quantum statistical entropy of
Reissner-Nordstrom black holes is
S=S1+S2+S3, where Si (i=1,2,3) is the entropy, contributed by regions
1,2,3. The detailed calculation shows that S2 is neglectfully
small. S1=wt(π2/45)kb(Ao/ε2β3), S3=-wt(π2/45)kb(Ai/ε2β3),
where Ao and Ai are, respectively, the areas of the
outer and inner event horizons, wt=2s[1-
2-(s+1)],
s=d/2, d is the space-time dimension, here d=4, s=2. As
ri approaches ro in the extreme case the total
quantum statistical entropy of Reissner-Nordstrom black holes approaches zero. 相似文献