World Journal of Condensed Matter Physics最新文献_第2页

Just a Bit of Physics Can Tell So Much: A Unique Story of the Start of the Earth-Moon System 一点点物理学就能说明这么多:地月系统起源的独特故事

World Journal of Condensed Matter Physics Pub Date : 2020-03-16 DOI: 10.4236/wjcmp.2020.102006

F. Cadieu

引用次数: 3

A Fermi Energy-Incorporated Framework for Dealing with the Temperature- and Magnetic Field-Dependent Critical Current Densities of Superconductors and Its Application to Bi-2212 超导体临界电流密度随温度和磁场变化的费米能量整合框架及其在Bi-2212中的应用

World Journal of Condensed Matter Physics Pub Date : 2020-03-16 DOI: 10.4236/wjcmp.2020.102004

G. P. Malik, V. S. Varma

{"title":"A Fermi Energy-Incorporated Framework for Dealing with the Temperature- and Magnetic Field-Dependent Critical Current Densities of Superconductors and Its Application to Bi-2212","authors":"G. P. Malik, V. S. Varma","doi":"10.4236/wjcmp.2020.102004","DOIUrl":"https://doi.org/10.4236/wjcmp.2020.102004","url":null,"abstract":"It is well known that the critical current density of a superconductor depends on its size, shape, nature of doping and the manner of preparation. It is suggested here that the collective effect of such differences for different samples of the same superconductor is to endow them with different values of the Fermi energy—a single property to which may be attributed the observed variation in their critical current densities. The study reported here extends our earlier work concerned with the generalized BCS equations [Malik, G.P. (2010) Physica B, 405, 3475-3481; Malik, G.P. (2013) WJCMP, 3,103-110]. We develop here for the first time a framework of microscopic equations that incorporates all of the following parameters of a superconductor: temperature, momentum of Cooper pairs, Fermi energy, applied magnetic field and critical current density. As an application of this framework, we address the different values of critical current densities of Bi-2212 for non-zero values of temperature and applied magnetic field that have been reported in the literature.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131911099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Quantum Curie-Weiss Magnet Induced by Violation of Cluster Property 违反团簇性质诱导的量子居里-魏斯磁体

World Journal of Condensed Matter Physics Pub Date : 2020-03-16 DOI: 10.4236/wjcmp.2020.102003

T. Munehisa

{"title":"Quantum Curie-Weiss Magnet Induced by Violation of Cluster Property","authors":"T. Munehisa","doi":"10.4236/wjcmp.2020.102003","DOIUrl":"https://doi.org/10.4236/wjcmp.2020.102003","url":null,"abstract":"There are some concepts that are accepted in our daily life but are not trivial in physics. One of them is the cluster property that means there exist no relations between two events which are sufficiently separated. In the works recently published by the author, the extensive and quantitative examination has been made about the violation of cluster property in the correlation function of the spin operator for the quantum spin system. These works have shown that, when we include the symmetry breaking interaction, the effect by the violation is proportional to the inverse of the system size. Therefore this effect is tinny since the system size is quite large. In order to find the effect due to the violation even when the size is large, we propose a new system where additional spins couple with the spin system on the square lattice, where the coupling constant between these systems being assumed to be small. Applying the perturbation theory, we obtain the effective Hamiltonian for the additional system. This Hamiltonian includes Curie-Weiss model that is induced by the violation of the cluster property. Then we find that this effective Hamiltonian has the factor which is the inverse of the system size. Since Curie-Weiss model, which is known to be exactly soluble, has to contain this factor so that the thermodynamical properties are well-defined, the essential factor for the Hamiltonian is determined by the coupling and the strength of the symmetry breaking interaction. Our conclusion is, therefore, that it is possible to observe the effect by the violation of the cluster property at the inverse temperature whose order is given by these parameters.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125678624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Induced Hall-Like Current by Acoustic Phonons in Semiconductor Fluorinated Carbon Nanotube 半导体氟化碳纳米管中声子诱导的类霍尔电流

World Journal of Condensed Matter Physics Pub Date : 2020-03-16 DOI: 10.4236/wjcmp.2020.102005

D. Sakyi-Arthur, S. Mensah, K. Adu, K. Dompreh, R. Edziah, N. G. Mensah, C. Jebuni-Adanu

{"title":"Induced Hall-Like Current by Acoustic Phonons in Semiconductor Fluorinated Carbon Nanotube","authors":"D. Sakyi-Arthur, S. Mensah, K. Adu, K. Dompreh, R. Edziah, N. G. Mensah, C. Jebuni-Adanu","doi":"10.4236/wjcmp.2020.102005","DOIUrl":"https://doi.org/10.4236/wjcmp.2020.102005","url":null,"abstract":"We show that Hall-like current can be induced by acoustic phonons in a nondegenerate, semiconductor fluorine-doped single-walled carbon nanotube (FSWCNT) using a tractable analytical approach in the hypersound regime (q is the modulus of the acoustic wavevector and is the electron mean free path). We observed a strong dependence of the Hall-like current on the magnetic field, H, the acoustic wave frequency, , the temperature, T, the overlapping integral, , and the acoustic wavenumber, q. Qualitatively, the Hall-like current exists even if the relaxation time does not depend on the carrier energy but has a strong spatial dispersion, and gives different results compared to that obtained in bulk semiconductors. For and , the Hall-like current is in the absence of an electric field and in the presence of an electric field at 300 K. Similarly, the surface electric field due to the Hall-like current is in the absence of an external electric field. In the presence of an external electric field, and for at 300 K. q and can be used to tune the Hall-like current and of the FSWCNT. This offers the potential for room temperature application as an acoustic switch or transistor, as well as a material for ultrasound current source density imaging (UCSDI) and AE hydrophone device in biomedical engineering.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131040243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Semiconductor Fluorinated Carbon Nanotube as a Low Voltage Current Amplifier Acoustic Device 半导体氟化碳纳米管作为一种低压电流放大声学器件

World Journal of Condensed Matter Physics Pub Date : 2020-01-23 DOI: 10.4236/wjcmp.2020.101002

D. Sakyi-Arthur, S. Mensah, K. Adu, K. Dompreh, R. Edziah, N. G. Mensah, C. Jebuni-Adanu

{"title":"Semiconductor Fluorinated Carbon Nanotube as a Low Voltage Current Amplifier Acoustic Device","authors":"D. Sakyi-Arthur, S. Mensah, K. Adu, K. Dompreh, R. Edziah, N. G. Mensah, C. Jebuni-Adanu","doi":"10.4236/wjcmp.2020.101002","DOIUrl":"https://doi.org/10.4236/wjcmp.2020.101002","url":null,"abstract":"Acoustoelectric effect (AE) in a non-degenerate fluorinated single walled carbon nanotube (FSWCNT) semiconductor was carried out using a tractable analytical approach in the hypersound regime , where q is the acoustic wavenumber and is the electron mean-free path. In the presence of an external electric field, a strong nonlinear dependence of the normalized AE current density , on ( is the electron drift velocity and is the speed of sound in the medium) was observed and depends on the acoustic wave frequency, , wavenumber q, temperature T and the electron-phonon interactions parameter, . When , decreases to a resonance minimum and increases again, where the FSWCNT is said to be amplifying the current. Conversely, when , rises to a maximum and starts to decrease, similar to the observed behaviour in negative differential conductivity which is a consequence of Bragg’s reflection at the band edges at T=300K. However, FSWCNT will offer the potential for room temperature application as an acoustic switch or transistor and also as a material for ultrasound current source density imaging (UCSDI) and AE hydrophone devices in biomedical engineering. Moreover, our results prove the feasibility of implementing chip-scale non-reciprocal acoustic devices in an FSWCNT platform through acoustoelectric amplification.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129370390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Acoustoelectric Effect in Fluorinated Carbon Nanotube in the Absence of External Electric Field 无外加电场条件下氟化碳纳米管的声电效应

World Journal of Condensed Matter Physics Pub Date : 2020-01-23 DOI: 10.4236/wjcmp.2020.101001

D. Sakyi-Arthur, S. Mensah, K. Adu, K. Dompreh, R. Edziah, N. G. Mensah

{"title":"Acoustoelectric Effect in Fluorinated Carbon Nanotube in the Absence of External Electric Field","authors":"D. Sakyi-Arthur, S. Mensah, K. Adu, K. Dompreh, R. Edziah, N. G. Mensah","doi":"10.4236/wjcmp.2020.101001","DOIUrl":"https://doi.org/10.4236/wjcmp.2020.101001","url":null,"abstract":"Acoustoelectric effect (AE) in a non-degenerate Fluorine modified single walled carbon nanotube (FSWCNT) semiconductor is studied theoretically using the Boltzmann’s transport equation. The study is done in the hypersound regime i.e. , where q is the acoustic phonon wavenumber and is the electron mean free path. The results obtained are compared with that of undoped single walled carbon nanotube (SWCNT). The AE current density for FSWCNT is observed to be four orders of magnitude smaller than that of undoped SWCNT with increasing temperature, that is . This is because the electron-phonon interactions in SWCNT are stronger than FSWCNT. Thus, there are more intra-mini-band electrons interacting with the acoustic phonons to generate a higher AE current in SWCNT than in FSWCNT. This has been observed experimentally, where the electrical resistance of FSWCNT is higher than pristine SWCNT i.e. . The study shows the potential for FSWCNT as an ultrasound current source density imaging (UCSDI) and AE hydrophone material. However, FSWCNT offers the potential for room temperature applications of acoustoelectric device but other techniques are needed to reduce the resistance.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126412168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

The Role of Pτ in the Photothermoelectric Effect and in Photoredox Catalysis Reactions Pτ在光热电效应和光氧化还原催化反应中的作用

World Journal of Condensed Matter Physics Pub Date : 2019-09-20 DOI: 10.4236/wjcmp.2019.94007

G. Scarel

{"title":"The Role of Pτ in the Photothermoelectric Effect and in Photoredox Catalysis Reactions","authors":"G. Scarel","doi":"10.4236/wjcmp.2019.94007","DOIUrl":"https://doi.org/10.4236/wjcmp.2019.94007","url":null,"abstract":"Context and Background: Recent research has shown that the amount of energy conserved in light-matter interaction is given by the product of light’s power P times its period τ , i.e. Pτ. To date, evidences of the validity of such finding are restricted to the interaction of light with capacitors, infrared spectroscopy, and vision in vertebrates. Motivation: In this article, we want to explore the validity of the role of Pτ in a broader range of phenomena. Hypothesis: We assume that the photothermoelectric (PTE) effect and photoredox catalysis reactions (PCRs) are manifestations of light-matter interaction and therefore have Pτ conserved in the process. Method: We take the data published in two articles, one on the PTE effect and the other on PCRs and revisit the data analysis of the authors of the original articles considering Pτ as the energy conserved. Results: In the case of the PTE effect, we unveil that the size of the light’s beam cross-sectional area impinging on the photodetectors plays a major role in defining the performance of the photodetectors. With our analysis, the photodetector responsivities actually turn out to be higher than those reported in the original article. In the case of the PCRs, we find that the magnitude of Pτ involved in successful PCRs is independent of the type of light used, whether near-infrared or blue. In addition, the involvement of Pτ in the description of PCRs helps to clarify the role of the law of conservation of energy, which was neglected by the authors of the original article. Conclusions: From this study, we infer that the hypothesis that Pτ that the hypothesis that represents the amount of energy conserved in light-matter interaction is valid and general, useful to measure device performance, and predict alternative processes to achieve desired outcomes.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132132345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Surface Recombination Concept as Applied to Determinate Silicon Solar Cell Base Optimum Thickness with Doping Level Effect 表面复合概念在掺杂水平效应下确定硅太阳电池基底最佳厚度中的应用

World Journal of Condensed Matter Physics Pub Date : 2019-09-20 DOI: 10.4236/wjcmp.2019.94008

Masse Samba Diop, Hamet Yoro Ba, N. Thiam, Ibrahima Diatta, Youssou Traoré, Mamadou Lamine Ba, E. Sow, Oulymata Mballo, G. Sissoko

引用次数: 13

On the Galvanic Modification of Seawater 海水的电改性研究

World Journal of Condensed Matter Physics Pub Date : 2019-09-20 DOI: 10.4236/wjcmp.2019.94009

A. Shimkevich

引用次数: 1

Interplay between Carrier Polarization, Spin-Orbit Coupling and Exchange Field on Anomalous Hall Conductivity in the Presence of Magnetic Impurity in Mn Doped GaAs 磁杂质存在下Mn掺杂GaAs中载流子极化、自旋轨道耦合和交换场对异常霍尔电导率的影响

World Journal of Condensed Matter Physics Pub Date : 2019-09-20 DOI: 10.4236/wjcmp.2019.94006

Lijalem Kelemu Shita

{"title":"Interplay between Carrier Polarization, Spin-Orbit Coupling and Exchange Field on Anomalous Hall Conductivity in the Presence of Magnetic Impurity in Mn Doped GaAs","authors":"Lijalem Kelemu Shita","doi":"10.4236/wjcmp.2019.94006","DOIUrl":"https://doi.org/10.4236/wjcmp.2019.94006","url":null,"abstract":"We develop a model Hamiltonian to treat anomalous Hall conductivity in dilute magnetic semiconductor (DMS) of type (III, Mn, V) considering the impurity potentials (potential due to interaction of spin of carriers with localized spin of dopant (Mn) and coulomb like potential). Using equation of motion in Green function together with Quantum Kubo-formula of conductivity, the anomalous Hall conductivity is calculated as function of spin-orbit coupling, exchange field and carrier polarization. The calculated result shows that at low impurity concentration, the interplay between spin polarization of carriers, spin-orbit coupling and exchange fields is crucial for existence of anomalous Hall conductivity. The monotonic increment of anomalous Hall conductivity with exchange field is observed for strong spin-orbit coupling limit. In weak spin-orbit coupling limit, the magnitude of anomalous Hall conductivity increases parabolically with the spin-orbit coupling. Our results provide an important basis for understanding the interplay between the spin polarization, spin-orbit coupling, and exchange field on anomalous Hall conductivity at low impurity concentration. The findings are also a key step to realize dissipationless quantum transport without external magnetic field.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129383764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0