期刊文献+
共找到9篇文章
< 1 >
每页显示 20 50 100
费米能级之近似计算 被引量:1
1
作者 黄瑞 马平平 《首都师范大学学报(自然科学版)》 1995年第4期52-58,共7页
在研究费米子系统的问题时,有一表示化学势与费米能级之间关系的近似等式:应用此式处理问题往往可使计算大为简化.本文重点讨论了该式的具体适用范围.经计算表明,对自然界已发现的金属元素的自由电子气体,直至它们的熔点以下,上... 在研究费米子系统的问题时,有一表示化学势与费米能级之间关系的近似等式:应用此式处理问题往往可使计算大为简化.本文重点讨论了该式的具体适用范围.经计算表明,对自然界已发现的金属元素的自由电子气体,直至它们的熔点以下,上式均有高度近似性.而对费米化学气体则只在极低温度时上式才成立,但那时有的气体已经液化了.文中还举例说明了应用该式处理问题的优越性. 展开更多
关键词 化学势 费米能级 费米温度 价电子 自由电子气体
下载PDF
谈温度概念
2
作者 高星林 《渤海学刊(哲学社会科学版)》 1990年第4期19-21,共3页
(一)初等物理学中的温度概念人类在实践中,凭着生理知觉能够直接感受到物体存在着冷热的不同,所以生活中很早就广泛运用着温暖、寒冷这样的词语(概念).中学物理教学中把表示物体冷热程度的物理量定义为温度,使广为人们熟知的观念得到了... (一)初等物理学中的温度概念人类在实践中,凭着生理知觉能够直接感受到物体存在着冷热的不同,所以生活中很早就广泛运用着温暖、寒冷这样的词语(概念).中学物理教学中把表示物体冷热程度的物理量定义为温度,使广为人们熟知的观念得到了具体的概括.由这样的定义可以定性地比较和说明在人的知觉允许范围内物体冷热程度的异同.但是,由于人的知觉的局限性,所以严格地说仅仅这样定义温度显然是不科学的.这样的定义也不能给出对于温度客观的,可以用数值定量表示的量度方法. 展开更多
关键词 中学物理教学 定量表示 温度 粒子数反转 热力学第零定律 定义式 统计物理 定域系 费米温度 单原子
下载PDF
普遍色散关系下的热波长 被引量:5
3
作者 严子浚 《大学物理》 北大核心 2001年第12期3-5,共3页
指出目前教科书和文献中所用的热波长概念仅适用于非相对论性系统 ,而本文引进了普遍热波长的概念 .由此可使理想量子气体的热力学函数表示成统一的简洁形式 ,并进一步揭示了热波长的物理内涵 .另外还导出玻色
关键词 热波长 热力学函数 BEC 临界温度 费米温度 统计物理学 物理教学 普遍热波长
下载PDF
Charged Fermions Tunneling from a Rotating Charged Black Hole in 5-Dimensional Gauged Supergravity
4
作者 李慧玲 林榕 王传银 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第11期849-853,共5页
Recent research shows that Hawking radiation from black hole horizon can be treated as a quantum tunneling process, and fermions tunneling method can successfully recover Hawking temperature. In this tunneling framewo... Recent research shows that Hawking radiation from black hole horizon can be treated as a quantum tunneling process, and fermions tunneling method can successfully recover Hawking temperature. In this tunneling framework, choosing a set of appropriate matrices γ^μ is an important technique for fermions tunneling method. In this paper, motivated by Kerner and Man's fermions tunneling method of 4 dimension black holes, we further improve the analysis to investigate Hawking tunneling radiation from a rotating charged black hole in 5-dimensional gauged supergravity by constructing a set of appropriate matrices γ^μ for general covariant Dirac equation. Finally, the expected Hawking temperature of the black hole is correctly recovered, which takes the same form as that obtained by other methods. This method is universal, and can also be directly extend to the other different-type 5-dimensional charged black holes. 展开更多
关键词 rotating charged black hole Dirac particles Hawking radiation Hawking temperature
下载PDF
原子吸收成像的二维光学密度分布获得量子简并费米气体参数 被引量:1
5
作者 王鹏军 熊德智 +1 位作者 陈海霞 张靖 《光学学报》 EI CAS CSCD 北大核心 2010年第3期893-897,共5页
从费米原子俘获在谐振势中出发,采用托马斯-费米的半经典近似(Thomas-Fermi approximation),计算了自旋极化费米子的空间分布函数,对费米原子吸收成像的光学密度分布进行拟合,分析得到粒子数,费米温度和实际温度。采用这种方法,对实验... 从费米原子俘获在谐振势中出发,采用托马斯-费米的半经典近似(Thomas-Fermi approximation),计算了自旋极化费米子的空间分布函数,对费米原子吸收成像的光学密度分布进行拟合,分析得到粒子数,费米温度和实际温度。采用这种方法,对实验中获得的^(40)K费米原子吸收成像的光学密度分布进行拟合,得到了费米气体量子简并参数T/T_F。 展开更多
关键词 简并费米气体 托马斯-费米近似 费米温度 费米简并气体参数
原文传递
Transport properties,upper critical field and anisotropy of Ba(Fe_(0.75)Ru_(0.25))_2As_2 single crystals 被引量:2
6
作者 XING Jie SHEN Bing +5 位作者 ZENG Bin LIU JianZhong DING XiaXin WANG ZhiHe YANG Huan WEN HaiHu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第12期2259-2263,共5页
The temperature and angle dependent resistivity of Ba(Fe 0.75 Ru 0.25) 2 As 2 single crystals were measured in magnetic fields up to 14 T.The temperature dependent resistivity with the magnetic field aligned parallel ... The temperature and angle dependent resistivity of Ba(Fe 0.75 Ru 0.25) 2 As 2 single crystals were measured in magnetic fields up to 14 T.The temperature dependent resistivity with the magnetic field aligned parallel to c-axis and ab-planes allow us to derive the slope of dH ab c2 /dT and dH c c2 /dT near T c yielding an anisotropy ratio Γ = dH ab c2 /dT/dH c c2 /dT ≈ 2.By scaling the curves of resistivity vs.angle measured at a fixed temperature but different magnetic fields within the framework of the anisotropic Ginzburg-Landau theory,we obtained the anisotropy in an alternative way.Again we found that the anisotropy(m c /m ab) 1/2 was close to 2.This value is similar to that in Ba0.6K0.4Fe2As2(K-doped Ba122) and Ba(Fe 0.92 Co 0.08) 2 As 2(Co-doped Ba122).This suggests that the 3D warping effect of the Fermi surface in Ru-doped samples may not be stronger than that in the K-doped or Co-doped Ba122 samples,therefore the possible nodes appearing in Ru-doped samples cannot be ascribed to the 3D warping effect of the Fermi surface. 展开更多
关键词 Ba(Fe 0.75 Ru 0.25) 2 As 2 transport properties ANISOTROPY
原文传递
A naive toy model of dark matter:Fermion sea
7
作者 ZHANG YuJie 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第6期1178-1178,共1页
A naive toy model that the fermion sea offers the dark matter density is discussed here.If the fermion sea fills the total space and the temperature equals the temperature of CMB,we can get the mass of the fermion is ... A naive toy model that the fermion sea offers the dark matter density is discussed here.If the fermion sea fills the total space and the temperature equals the temperature of CMB,we can get the mass of the fermion is about 4.7×10 38 kg (0.026 eV). 展开更多
关键词 dark matter fermion sea CMB temperature
原文传递
Dual fermion condensate and phase transition in QED_3
8
作者 FENG HongTao YIN PeiLin +1 位作者 SUN WeiMin ZONG HongShi 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第6期1116-1119,共4页
In this paper,we investigate the behaviors of dual fermion condensate in QED 3 under variation of temperature.By means of Dyson-Schwinger equation for the fermion propagator,we extract the dual fermion condensate and ... In this paper,we investigate the behaviors of dual fermion condensate in QED 3 under variation of temperature.By means of Dyson-Schwinger equation for the fermion propagator,we extract the dual fermion condensate and compare its behavior with the ordinary chiral fermion condensate and the chiral susceptibility.It is found that the dual fermion condensate cannot be regarded as the order parameter for the confinement-deconfinement phase transition in QED 3.Furthermore,the change of the dual fermion condensate around the chiral phase transition point observed in the present work must therefore be interpreted as solely induced by the chiral transition. 展开更多
关键词 QED 3 dual fermion condensate deconfinement phase transition chiral phase transition
原文传递
Scalars and Neutral Fermions on the Background with Hyperscaling Violation
9
作者 白楠 方超 +2 位作者 高怡泓 奇官布 徐孝宝 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第12期714-720,共7页
We study the scalar and fermionic retarded Green's function on the background with hyperscMing violation by means of the prescriptions proposed in [J. High Eergy Phys. 09 (2002) 042; Fortsch. Phys. 57 (2009) 367]... We study the scalar and fermionic retarded Green's function on the background with hyperscMing violation by means of the prescriptions proposed in [J. High Eergy Phys. 09 (2002) 042; Fortsch. Phys. 57 (2009) 367]. For scalar field, we consider both massless and massive cases, and for spinor field, we further calculate the finite temperature correlator with the black hole background. 展开更多
关键词 gauge string duality
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部