Current Location:home > Browse



Your conditions: Physics(1,943)

1. chinaXiv:202101.00003 [pdf]

On dark matter

Xian-Qiao Yu
Subjects: Physics >> The Physics of Elementary Particles and Fields

In this article, I shall propose a new model of dark matter, in which I introduce a neutral primordial axial-vector field, which is a new field beyond the standard model. All the standard model elementary particles are produced spontaneously from this field in the Big Bang epoch of the universe and then these produced elementary particles decayed or annihilated in the well-known standard model interactions. The relic of the primordial axial-vector field appears in a form of vacuum energy can not only give naturally the correct abundance of dark matter in the present universe, but provide a natural solution to the cosmological constant problem as well. Some possible experiments for testing the new theory of dark matter are also suggested in this article.

submitted time 2021-03-29 Hits1767Downloads376 Comment 0

2. chinaXiv:202103.00131 [pdf]

Direct-writing of two-dimensional diodes by focused ion beams

Tan Yang
Subjects: Physics >> Interdisciplinary Physics and Related Areas of Science and Technology

In the past decade, electronic devices based on graphene and the related two-dimensional (2D) materials have exhibited outstanding figures of merit. However, so far, the fabrication of two-dimensional diodes, as elementary building blocks of electronic devices, still relies on manual or semi-automated handling processing. To unleash their commercial potential, the integration of 2D materials into a fully-automated fabrication line is a critical step. Here, we elucidate the focused ion-beam writing as an automated approach to construct lateral diodes on a 2D heterostructure (MoSe2/G) consisting of the stacked monolayer graphene and MoSe2. Se-defects generated by focused ion writing endow the 2D heterostructure with unique electronic properties like the adjustable work function and the quasi-metallic state, which allows for the construction of the barrier at the boundary of the writing and non-writing region. Benefiting from this feature, the ion-beam-written heterostructure is used to realize rectifying and current regulating diodes. Exhibiting comparable performance to traditional diodes, the rectifying diode has a rectification ratio of ~104, while the current regulative diode has a dynamic resistance larger than 4.5 MΩ. Furthermore, to illustrate practical applications of these diodes in digital logic electronics, AND and OR logic gates are directly inscribed on the heterostructure by ion beams. Our work demonstrates the focused ion-beam writing as an additional strategy for direct-writing of 2D diodes on graphene-based heterostructures.

submitted time 2021-03-24 Hits360Downloads203 Comment 0

3. chinaXiv:202103.00135 [pdf]

New ordinal relative fuzzy entropy

Yuanpeng He
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

In real life, occurrences of a series of things are supposed to come in an order. Therefore, it is necessary to regard sequence as a crucial factor in managing different kinds of things in fuzzy environment. However, few related researches have been made to provided a reasonable solution to this demand. Therefore, how to measure degree of uncertainty of ordinal fuzzy sets is still an open issue. To address this issue, a novel ordinal relative fuzzy entropy is proposed in this paper taking orders of propositions into consideration in measuring level of uncertainty in fuzzy environment. Compared with previously proposed entropies, effects on degrees of fuzzy uncertainty brought by sequences of sequential propositions are embodied in values of measurement using proposed method in this article. Moreover, some numerical examples are offered to verify the correctness and validity of the proposed entropy.

submitted time 2021-03-23 Hits196Downloads123 Comment 0

4. chinaXiv:202103.00111 [pdf]


蒿巧利; 赵晏强; 周伯柱; 李印结
Subjects: Astronomy >> Astrometry
Subjects: Physics >> Atomic and Molecular Physics

2015年激光干涉仪引力波天文台(Laser Interferometer Gravitational-wave Observatory,LIGO)直接检测到引力波信号,为新物理学和天体物理学带来希望的同时,也掀起激光干涉仪引力波探测器发展的新浪潮。在激光干涉仪引力波探测器从地面到太空蓬勃发展的大背景下,本文从建设历程、技术特色和发展定位、运营模式等方面,开展各探测器的对比研究,归纳出激光干涉仪引力波探测器建设和运营的经验启示,即:激光干涉仪引力波探测器的建设是长期化工程,有助于推动科研容错机制和科学评价机制的完善发展;激光干涉仪引力波探测器的建设是高科技工程,有助于推动多学科技术协同发展;激光干涉仪引力波探测器的建设是国际化工程,有助于推动科研合作健康发展。

submitted time 2021-03-05 Hits2225Downloads617 Comment 0

5. chinaXiv:202103.00069 [pdf]


Subjects: Physics >> Nuclear Physics

本文讨论了常规电子直线加速器的设计问题, 并以一台 10 MeV 的电子直线加速器为例穿插其中讨论了常规电子直线加速器的设计。常规电子直线加速器由电子枪、聚束部分、光速部分所组成,而且在直线对撞机装置、自由电子激光装置中经常用到束团压缩部分。我们对每一部分都进行了分析与讨论,主要包括纵向、横向束流动力学方面, 总结了一系列的行之有效的设计思想与方法。

submitted time 2021-03-03 Hits1115Downloads300 Comment 0

6. chinaXiv:202103.00045 [pdf]


秦洁; 司建华; 贾冰; 赵春彦; 李端; 罗欢; 任立新
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.


submitted time 2021-03-02 From cooperative journals:《干旱区研究》 Hits971Downloads188 Comment 0

7. chinaXiv:202103.00011 [pdf]


Subjects: Physics >> The Physics of Elementary Particles and Fields


submitted time 2021-02-26 Hits950Downloads155 Comment 0

8. chinaXiv:201904.00075 [pdf]

A new approach to characterize the violation of Lorentz invariance

Subjects: Physics >> Geophysics, Astronomy, and Astrophysics


submitted time 2021-02-25 Hits14782Downloads707 Comment 0

9. chinaXiv:202102.00080 [pdf]

Development of X-ray spectrometer automatic adjustment system based on global optimization algorithm

Fei Zhan
Subjects: Physics >> Nuclear Physics

In high energy resolution X-ray spectroscopy beamlines of synchrotron radiation (SR) facilities and laboratory XAS/XES spectrometer, it is important to keep X-ray spectrometer operating in optimal conditions. The adjusting process is normally very time consuming due to the irregular light source beam point, and it is difficult to get global optimum. This study aims to develop an intelligent adjusting system based on global optimization algorithm for spectrometers on SR beamlines and on laboratory x-ray source. First of all, based on the two dimensional experimental data, automatic adjustment process was established. Then the automatic optimization was applied to adjust X-ray spectrometer practically, and upgraded iteratively. The online testing is carried out on a self-developed laboratory XAS spectrometer. Online tests results show that this automatic adjustment process converges to the optimal solution quickly, and the convergence time is about several dozens to hundreds steps, more efficient than manual optimization process. After automatic adjustment, we can get correct X-ray absorption spectrum based on the adjusted spectrometer.

submitted time 2021-02-25 Hits1302Downloads200 Comment 0

10. chinaXiv:202102.00029 [pdf]


Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.


submitted time 2021-02-14 Hits1571Downloads284 Comment 0

12345678910  Last  Go  [195 Pages/ 1943 Totals]