排序方式: 共有16条查询结果,搜索用时 15 毫秒
1.
ZverovichIE ZverovichOI 《高校应用数学学报(英文版)》2004,19(2):125-132
Two new hereditary classes of P5-free graphs where the stability number can be found in polynomial time are proposed. They generalize several known results. 相似文献
2.
Abstract We have already reported the results of direct observations of electron-topological phase transition (ETT) in cadmium'. The appearance of new dHvA-frequencies corresponding to the Fermi surface (FS) change, i.e. restoring of folding of hole “monster” and electron “needle” appearance is observed under pressure. In t h i s report we are going to enlarge on the ETT consequences study in cadmium-on the advent of anomalous electronic features in transverse magnetoresistance and thermoelectric power. 相似文献
3.
E. M. Dizhur A. N. Voronovsky E. S. Itskevich I. N. Kotel'nikov A. Ya. Shul'man 《高压研究》2013,33(1-6):370-373
Abstract Summary A new type of oscilations on tunneling conductance versus applied bias with a characteristic scale of > 40 mV and magnitude ~ 1 p.c. has been observed at 77 K for Au/GaAs:Te junction. The oscillations were enhanced by lighting with the GaP LED and conserved for a long time after switching the LED off. The proposed model explains the observed impurity oscillations by spatial modulations of the Schottky barrier with the impurity substitution and associates the pressure influence on the 0s cillations with changes in band structure of GaAs and with capture of ele ctrons by DX-centers. 相似文献
4.
Zverovich I E 《高校应用数学学报(英文版)》2004,19(3):239-244
§1 IntroductionLet G be a graph with vertex-set V(G) ={ v1 ,v2 ,...,vn} .A labeling of G is a bijectionL:V(G)→{ 1,2 ,...,n} ,where L (vi) is the label of a vertex vi.A labeled graph is anordered pair (G,L) consisting of a graph G and its labeling L.Definition1.An increasing nonconsecutive path in a labeled graph(G,L) is a path(u1 ,u2 ,...,uk) in G such thatL(ui) + 1相似文献
5.
A. N. Voronovskii E. M. Dizhur E. S. Itskevich L. M. Kashirskaya R. A. Stradling 《Physics of the Solid State》1997,39(4):637-640
Measurements of magnetoresistance and Hall emf have been carried out on GaSb/InAs/GaSb quantum wells of different thickness
and with interfaces of different types in fields up to 7 T and at pressures up to 2.5 GPa at 4.2 K. The pressure dependence
of the electron and hole concentrations was derived by analysis of Shubnikov-de Haas oscillations and magnetoresistance tensor
components, made in terms of the classical model operating with carriers of two types. It is shown that pressure initiates
a transition from semimetallic to semiconducting regime.
Fiz. Tverd. Tela (St. Petersburg) 39, 723–726 (April 1997) 相似文献
6.
S. L. Bud'ko A. G. Gapotchenko E. S. Itskevich V. F. Kraidenov A. V. Kuznetsov A. P. Menushenkov 《高压研究》2013,33(5-6):307-309
Abstract Extraordinary properties of superconductive BaPb, -xBixO, (BPB) led to the assumption of out-of-ordinary mechanism of the superconductivity of localized pairs1,2 相似文献
7.
通过在NF-3低速风洞专门研制的翼型模型及相应的俯仰和沉浮振动机构,选用NACA0012翼型进行大迎角下不同频率的振动实验,研究了模型振动平均状态下对其气动力特性的影响情况,并在N-S方程基础上对振动流场进行了初步分析。实验与计算研究的结果表明:在临近定常失速迎角的大迎角条件下,翼型的振动可以引起旋涡分离,导致翼型升力减小和失速迎角的提前;就所讨论的两种振动模式而言,俯仰振动的影响大于沉浮振动。所以,为了提高飞机模型,尤其是大展弦比飞机模型的风洞实验精准度,在模型设计和加工时要特别注意加强机翼弦向的扭转刚度。 相似文献
8.
Fry PW Itskevich IE Mowbray DJ Skolnick MS Finley JJ Barker JA O'Reilly EP Wilson LR Larkin IA Maksym PA Hopkinson M Al-Khafaji M David JP Cullis AG Hill G Clark JC 《Physical review letters》2000,84(4):733-736
New information on the electron-hole wave functions in InAs-GaAs self-assembled quantum dots is deduced from Stark effect spectroscopy. Most unexpectedly it is shown that the hole is localized towards the top of the dot, above the electron, an alignment that is inverted relative to the predictions of all recent calculations. We are able to obtain new information on the structure and composition of buried quantum dots from modeling of the data. We also demonstrate that the excited state transitions arise from lateral quantization and that tuning through the inhomogeneous distribution of dot energies can be achieved by variation of electric field. 相似文献
9.
E. S. Itskevich 《Journal of Experimental and Theoretical Physics》1998,86(4):805-810
A study is made of the properties of the homologous series of mercury HTSC-cuprates HgBa2Can−1CunO2n
+2+δ with n=1–8. Experiments are conducted under pressure for samples with n=1–5. The Hg-1223 and Hg-1234 phases were synthesized using a controlled high pressure chamber. The oxygen content of an initial
mixture corresponding to the Hg-1234 phase was varied by changing the composition of the initial BaO/BaO2 oxides. The dependence of the superconducting transition temperature T
c
on the lattice constant a (and, therefore, on the oxygen content) and of T
c
max
and dT
c
max
/dp on n are convex upward up to n=4, 5. The maximum values always correspond to the Hg-1223 phase. Experimental T
c
max
(n) curves for the phases with n=1–6 and dT
c
max
/dp curves for n=1–5 are compared with Anderson’s theory (the so-called RVB model). A general analysis of these results indicates that the
mercury cuprates have an ideal structure for HTSC. The Hg-1223 phase is the “champion” in this ideal structure and the critical
temperature corresponding to this phase (T
c
=135 K) is the highest at atmospheric pressure.
Zh. éksp. Teor. Fiz. 113, 1474–1483 (April 1998) 相似文献
10.
P. W. Fry I. E. Itskevich D. J. Mowbray M. S. Skolnick J. A. Barker E. P. O'Reilly L. R. Wilson P. A. Maksym M. Hopkinson M. Al-Khafaji J. P. R. David A. G. Cullis G. Hill J. C. Clark 《Physica E: Low-dimensional Systems and Nanostructures》2000,7(3-4)
The nature of the confined electronic states in InAs/GaAs self-assembled quantum dots is studied using photocurrent spectroscopy measured as a function of applied electric field. A field asymmetry of the quantum confined Stark effect is observed, consistent with the dots possessing a permanent dipole moment. The sign of this dipole indicates that for zero field the hole wave function lies above that of the electron, in disagreement with the predictions of all recent calculations. Comparison with a theoretical model demonstrates that the experimentally determined alignment of the electron and hole can only be explained if the dots contain a non-zero and non-uniform Ga content. 相似文献