Spin splitting modulated by uniaxial stress in InAs nanowires

We theoretically study the electronic structure, spin splitting, effective mass, and spin orientation of InAs nanowires with cylindrical symmetry in the presence of an external electric field and uniaxial stress. Using an eight-band k center dot p theoretical model, we deduce a formula for the spin splitting in the system, indicating that the spin splitting under uniaxial stress is a nonlinear function of the momentum and the electric field. The spin splitting can be described by a linear Rashba model when the wavevector and the electric field are sufficiently small. Our numeric results show that the uniaxial stress can modulate the spin splitting. With the increase of wavevector, the uniaxial tensile stress first restrains and then amplifies the spin splitting of the lowest electron state compared to the no strain case. The reverse is true under a compression. Moreover, strong spin splitting can be induced by compression when the top of the valence band is close to the bottom of the conductance band, and the spin orientations of the electron stay almost unchanged before the overlap of the two bands.

Dependence of the cross sections for Ir isotopes on the values of Qgg in the heavy ion collision

197Au were irradiated with 47 MeV/u 12C ions. Iridium was produced via the multinucleon transfer reactions in bombardments of 197Au with 12C. and was separated radiochemically from Au and the mixture of the reaction products. The γ radioactivities of Ir isotopes were measured by using a HPGe detector. The production cross sections of Ir isotopes were determined from activities of Ir isotopes at the end of bombardment and the other relative data. It has been found that the cross sections for neutron-rich iso...

Electric-dipole transitions in 165Er

High-spin states of 165Er were studied using the 160Gd(9Be, 4n)reaction at beam energies of 42 and 45 MeV. The previously known bands based on the ν5/2-[523] and ν5/2+[642] configurations have been extended to high-spin states. Electric-dipole transitions linking these two opposite parity bands were observed. Relatively large B(E1) values have been extracted experimentally and were attributed to octupole softness.

缺中子~(176)Ir核β~+／EC衰变研究

在210MeV的束流能量下,利用重离子熔合蒸发反应146Nd(35Cl,5nγ)176Ir产生具有β+／EC衰变性质的核素176Ir,由氦喷嘴快速带传输系统将反应产物传送到低本底区进行测量．经过实验数据的离线处理分析,对早先发表的176Ir衰变γ跃迁进行确认的同时又发现了3个新能级和10条新的γ射线, 丰富了176Os核的低位激发态能级纲图．并根据典型γ射线的衰变时间谱建议了176Ir核的一个长寿命的低自旋同核异能态．

双奇核~(176)Ir转动带的旋称反转(英文)

利用1 4 9Sm( 31 P ,4nγ)反应 ,通过γ射线的激发函数测量、X γ和γ γ符合测量研究了双奇核1 76Ir的高自旋态 .首次建立了双奇核1 76Ir由 4个转动带构成的能级纲图 .依据从实验数据中提取出的带内B(M1 ) B(E2 )值与理论计算值的比较 ,以及相邻双奇核的带结构特征 ,给出了转动带的准粒子组态 .基于本实验建立起的带间跃迁和在I=1 8处观测到的旋称交叉 ,指出1 76Ir核基于πh9 2 νi1 3 2 和πi1 3 2 νi1 3 2 组态的两个转动带在低自旋时出现旋称反转现象 .

Multi-quasiparticle gamma-band structure in neutron-deficient Ce and Nd isotopes

The newly developed multi-quasiparticle triaxial projected shell model approach is employed to study the high-spin band structures in neutron-deficient even-even Ce- and Nd-isotopes. It is observed that gamma-bands are built on each intrinsic configuration of the triaxial mean-field deformation. Due to the fact that a triaxial configuration is a superposition of several K-states, the projection from these states results in several low-lying bands originating from the same intrinsic configuration. This generalizes the well-known concept of the surface gamma-oscillation in deformed nuclei based on the ground-state to gamma-bands built on multi-quasiparticle configurations. This new feature provides an alternative explanation on the observation of two I = 10 aligning states in Ce-134 and both exhibiting a neutron character. (C) 2009 Elsevier B.V. All rights reserved.

Possible magnetic and antimagnetic rotations in Dy-144

High spin states of Dy-144 have been studied through in-beam gamma-ray spectroscopy by using the reaction Mo-92(Fe-56,2p2n). It has been found that the continuation of the ground-state band forks into three Delta I=2 bands above the 8(+) state. This forking has been attributed to the alignments of pi h(11/2)(2) or nu h(11/2)(-2) configurations with the help of the systematics in neighboring nuclei. Additionally a negative-parity sideband of Delta I=2 cascades has been observed to start from the 5((-)) state and continue to a dipole band above the (13(-)) state through another negative-parity sideband of Delta I=2 cascades in between. These structures have been discussed from the viewpoint of a competition between "Magnetic Rotation" and "Anti-magnetic Rotation" based on a classical particles-plus-rotor model.