液氦薄膜表面电子-涟波子系统的有效质量

研究了液氦薄膜表面电子与涟波弱耦合的性质，采用线性组合算符和微扰法导出电子－涟波子系统的有效质量。当计及电子在反冲效应中发射和吸收不同波矢的涟波子之间相互作用时，讨论对电子－涟波子系统有效质量的影响。     

磁场中液氦薄膜表面电子涟波子系统的性质

研究了磁场中液氦薄膜表面电子与涟波子强耦合和弱耦合的性质。采用线性组合算符方法导出磁场中液氦薄膜表面电子 涟波子系统的振动频率和基态能量。讨论磁场对表面电子 涟波子系统的振动频率和基态能量的影响。     

超导磁体用金属液氦广口杜瓦的研制

文中较详细地介绍了超导磁体用金属液氦广口杜瓦的结构、制作工艺、绝热计算。该杜瓦外径Φ40 0 ,总高 2 5 0 0 ,内胆Φ 3 0 5 ,深 1 80 0 ;绝热方式采用多屏多层超级绝热结构 ,液氦日蒸发量 7.5升。     

采用从头计算方法研究液态氦原子间等效对势

 提出了一种具有体心立方排列的原子团簇He₉模型,用于模拟液氦中邻近原子的近程平均分布特征,并运用量子从头计算方法和原子团簇理论计算技术,首次从理论上计算了液态氦原子间等效作用对势。计算给出的等效对势能较好地再现液氦的等温压缩线及冲击压缩线,所提出的液体等效结构的原子团簇模型能比较合理地描述液氦近程结构特征以及原子间多体相互作用规律。还将理论对势函数与经验Exp-6势进行了比较。     

Helium gas-bubble formation and blistering in metallic glass Ni45Fe5Co20Cr10Mo4Bl6

We report here the formation of helium gas bubbles in a nickel based metallic glass Ni₄₅Fe₅Co₂₀Cr₁₀Mo₄B_l6 after 50 keV helium ion irradiations at room temperature studied by transmission electron microscopy. At higher doses bubbles eventually grow and deform the material surface plastically leading to blister formation. Critical dose for blister formation is determined. Helium gas bubble formation is associated with partial crystallisation of the glass which can be observed from selected area diffraction from the region where bubbles are formed. Micro-hardness measurements are also performed on the irradiated samples as a function of dose. Increase in the microhardness has been observed after a dose at which helium bubbles are formed.     

From Defiant Youth to Conformist Adulthood: The Sad Story of Liquid Helium

In this paper I discuss the properties of superfluid helium and present the different approaches to the problem of superfluidity. The gradual realization of this new liquid state brought about dramatic changes in our assessment of quantum mechanics and our reconceptualization of fluids, especially with the introduction of the notion of macroscopic quantum phenomena, which was introduced for superconductivity and superfluidity by Fritz London.     

Nuclear structure of the yrast 6+, 10+ and 14− states in106Sn

The nuclear precession of¹⁰⁶Sn in the 6⁺ state was measured relative to that of¹⁰⁸Sn by the IPAD method: θ(6⁺;¹⁰⁶Sn)/θ(6⁺;¹⁰⁸Sn)=1.06(33). Available data on the 6⁺ state in¹⁰⁸Sn giveg (6⁺;¹⁰⁶Sn)=? 0.14(9), which is consistent with the seniority ν=2 configuration: ({ie133-01}). B(E2; 10⁺→ 8⁺) was measured to be 6.4(10) W.u. for¹⁰⁶Sn and 0.62(5) W.u. for¹⁰⁸Sn. This difference could not be explained by the ν≦4 configurations. The {ie133-02}→13^? transition turned out to be an M1/ E2 mixed transition and so the yrast I=14 state was identified with a state of the νh_11/2 band.     

Conduction of Strongly Coupled Electrons Through Narrow Channels on Liquid Helium Surface: Simulation

The conduction of electrons through narrow channels formed on the surface of liquid helium is analyzed by numerical simulations. It is shown that, when electrons are strongly coupled, we have nonlinear and even negative dependence of conductance on the width of the constriction which is controlled by the gate voltage (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

基于双晶退火衬底的高温超导纳米量子干涉仪在液氦液氮温区下的输运特性

超导纳米量子干涉器件是近年来发展起来的一种新型超导器件, 通过现代微纳加工技术将其超导环缩小到纳米尺寸, 构成高度灵敏的微观自旋探测器, 理论上可以达到测量单电子自旋的灵敏度. 同时, 高温超导由于具有较高的临界温度和上临界场也备受关注. 然而, 相比于低温超导量子干涉器件, 高温超导量子干涉器件的1/f 噪声更加显著, 这限制了其在低频下的应用. 本文基于双晶衬底技术, 通过聚焦离子束加工制备高温超导纳米量子干涉仪, 并对其在液氦和液氮温区下的电学性能、4.2 K 下的磁通噪声进行表征. 实验发现, 通过预先退火处理钛酸锶双晶衬底, 可以有效改善衬底表面的粗糙度, 进而优化高温超导纳米量子干涉仪的1/f 磁通噪声. 最终得到低频下(1 Hz)的磁通噪声灵敏度为4.9 μΦ0/Hz1/2 , 比未事先预处理的小一到两个数量级, 这对于推进高温超导纳米量子干涉器件在低频下的应用意义重大.