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Ultra-high sensitivity accelerometers and gyroscopes using neutral atom matter-wave interferometry 使用中性原子物质波干涉测量的超高灵敏度加速度计和陀螺仪
Physica B+C Pub Date : 1988-07-01 DOI: 10.1016/0378-4363(88)90176-3
John F. Clauser
{"title":"Ultra-high sensitivity accelerometers and gyroscopes using neutral atom matter-wave interferometry","authors":"John F. Clauser","doi":"10.1016/0378-4363(88)90176-3","DOIUrl":"10.1016/0378-4363(88)90176-3","url":null,"abstract":"<div><p>This paper shows that matter-wave interferometers employing low-velocity neutral atoms can be used as inertial sensors with sensitivities that exceed those of conventional mechanical sensors and multiple circuit optical interferometers by many powers of ten. The energy and mass dependence of the phase shifts that are due to rotation and acceleration are different. Thus a pair of interferometers with different energies and/or masses can perform simultaneous independent measurements of rotation and acceleration. A proposed configuration is one formed by a sequence of planar diffraction gratings operating in high order. Gratings consist of near-resonant standing-wave laser beams. Laser decelerated and cooled atomic beams provide a suitable source. Path curvature due to acceleration and rotation is canceled by magnetic field gradients that produce an effective magnetic levitation of the atoms in a feedback arrangement that maintains null phase shift.</p></div>","PeriodicalId":101023,"journal":{"name":"Physica B+C","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0378-4363(88)90176-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78682512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 123
Neutron diffraction by perfect crystals excited into mechanical resonance vibrations 中子衍射由完美晶体激发成机械共振振动
Physica B+C Pub Date : 1988-07-01 DOI: 10.1016/0378-4363(88)90154-4
Rudolf Michalec, Pavel Mikula, Miroslav Vrána, Jiří Kulda, Bohumil Chalupa, Ludmila Sedláková
{"title":"Neutron diffraction by perfect crystals excited into mechanical resonance vibrations","authors":"Rudolf Michalec,&nbsp;Pavel Mikula,&nbsp;Miroslav Vrána,&nbsp;Jiří Kulda,&nbsp;Bohumil Chalupa,&nbsp;Ludmila Sedláková","doi":"10.1016/0378-4363(88)90154-4","DOIUrl":"https://doi.org/10.1016/0378-4363(88)90154-4","url":null,"abstract":"<div><p>Our contribution presents results of investigations concerning neutron diffraction by vibrating perfect crystals of Si and SiO<sub>2</sub>. They were excited in longitudinal, flexural, thickness and thickness-shear modes of vibration with resonance frequencies ranging from 1 to 1500 kHz. In this case, when the acoustic wavelength is much larger than the extinction distance the following phenomena caused by the deformation and Doppler shift were observed: broadening of the perfect crystal rocking curve, enhancement of the integrated reflectivity by up to two orders of magnitude and time modulation of the diffracted beam. When neutron time-off-flight through the vibrating crystal is comparable to the vibration period, multiple reflections having influence on the reflectivity take place. While investigating the forbidden reflections in the crystal excited into vibrations, a strong multiple diffraction phenomena resulting in “umweganregung” effect was observed. Also the vibrating crystals as neutron choppers with 1 μs pulses and a repetition rate of up to 100 kHz were treated.</p></div>","PeriodicalId":101023,"journal":{"name":"Physica B+C","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0378-4363(88)90154-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91721018","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
Novel measuring methods in neutron interferometry 中子干涉测量新方法
Physica B+C Pub Date : 1988-07-01 DOI: 10.1016/0378-4363(88)90151-9
D. Tuppinger, H. Rauch, J. Summhammer
{"title":"Novel measuring methods in neutron interferometry","authors":"D. Tuppinger,&nbsp;H. Rauch,&nbsp;J. Summhammer","doi":"10.1016/0378-4363(88)90151-9","DOIUrl":"https://doi.org/10.1016/0378-4363(88)90151-9","url":null,"abstract":"<div><p>Perfect crystal interferometry is becoming a standard tool for precise measurements of coherent scattering lengths. So far accuracy was limited by the resolution achieved with the determination of the wavelength and the wavelength distribution. The newly tested nondispersive sample arrangement avoids this shortcoming because the phase shift becomes independent of the wavelength. Arbitrarily shaped samples can be measured by an adapted Christiansen filter method, where the scattering length density of the powdered sample is matched to the scattering length density of a surrounding liquid. The following values for the bound coherent scattering lengths were determined: <em>b</em><sub><em>c</em></sub>(Bi) = 8.5165(62) fm by the standard method, <em>b</em><sub><em>c</em></sub>(Bi) = 8.521(4) fm by the nondispersive method and <em>b</em><sub><em>c</em></sub>(Si) = 4.157(3) fm by the Christiansen filter method. A phase sensitivity of 2.2 × 10<sup>−5</sup> was achieved, which could easily be increased to a level of 10<sup>−6</sup>.</p></div>","PeriodicalId":101023,"journal":{"name":"Physica B+C","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0378-4363(88)90151-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91721021","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: 5
Schrödinger inviolate: Neutron optical searches for violations of quantum mechanics Schrödinger inviolate:中子光学搜索违反量子力学的行为
Physica B+C Pub Date : 1988-07-01 DOI: 10.1016/0378-4363(88)90143-X
A.G. Klein
{"title":"Schrödinger inviolate: Neutron optical searches for violations of quantum mechanics","authors":"A.G. Klein","doi":"10.1016/0378-4363(88)90143-X","DOIUrl":"https://doi.org/10.1016/0378-4363(88)90143-X","url":null,"abstract":"<div><p>A number of neutron optical experiments carried out over the past decade have searched for possible violations of the Schrödinger equation. Among the hypothetical effects considered were: non-linearities, the effects of quantum gravity and quanternionic forms. The relevant experiments are reviewed along with some new proposals.</p></div>","PeriodicalId":101023,"journal":{"name":"Physica B+C","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0378-4363(88)90143-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91721026","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: 33
Schrödinger equation for neutron optics Schrödinger中子光学方程
Physica B+C Pub Date : 1988-07-01 DOI: 10.1016/0378-4363(88)90160-X
V.F. Sears
{"title":"Schrödinger equation for neutron optics","authors":"V.F. Sears","doi":"10.1016/0378-4363(88)90160-X","DOIUrl":"10.1016/0378-4363(88)90160-X","url":null,"abstract":"<div><p>It is usually assumed that neutron optical phenomena are adequately described by a one-body Schrödinger equation containing a complex optical potential that is given by the average value of the Fermi pseudopotential. The main problem with this elementary approach is that it only includes the attenuation of the neutron wave function in the medium resulting from absorption, and neglects the often more important contribution to the attenuation from diffuse scattering which is also present in reality. The purpose of this paper is to show how the rigorous theory of dispersion overcomes the above problem by taking properly into account the local field effects and a correction to the scattering amplitude that are neglected in the elementary theory. The importance of the local field correction in some current measurements of neutron scattering lengths by neutron optical experiments is also indicated.</p></div>","PeriodicalId":101023,"journal":{"name":"Physica B+C","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0378-4363(88)90160-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86070881","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
Theory of Jahn-Teller interaction in metallocenes 茂金属中的Jahn-Teller相互作用理论
Physica B+C Pub Date : 1988-06-01 DOI: 10.1016/0378-4363(88)90083-6
R. Rai
{"title":"Theory of Jahn-Teller interaction in metallocenes","authors":"R. Rai","doi":"10.1016/0378-4363(88)90083-6","DOIUrl":"10.1016/0378-4363(88)90083-6","url":null,"abstract":"<div><p>The <sup>3</sup>E<sub>2g</sub>(e<sup>3</sup><sub>2g</sub>a<sup>1</sup><sub>1g</sub>) ground state of chromocene is treated as a system consisting of two holes, one in the e<sub>2g</sub> and the other in the a<sub>1g</sub> orbital. By a suitable choice of the basis vectors the vibronic eigenvalue equations of this case are transformed into isomorphic forms to the corresponding equation for the one electron case. The method of canonical transformation and variational approach developed in part I therefore is applied to chromocene also. The variational wavefunctions and energies are used to explain the EPR and Raman spectroscopy results on the complex.</p></div>","PeriodicalId":101023,"journal":{"name":"Physica B+C","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0378-4363(88)90083-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75789672","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
Light squeezing in the two-atom one-mode model with multi-photon transitions 具有多光子跃迁的双原子单模模型中的光压缩
Physica B+C Pub Date : 1988-06-01 DOI: 10.1016/0378-4363(88)90087-3
Fam Le Kien, E.P. Kadantseva, A.S. Shumovsky
{"title":"Light squeezing in the two-atom one-mode model with multi-photon transitions","authors":"Fam Le Kien,&nbsp;E.P. Kadantseva,&nbsp;A.S. Shumovsky","doi":"10.1016/0378-4363(88)90087-3","DOIUrl":"10.1016/0378-4363(88)90087-3","url":null,"abstract":"<div><p>The generation of squeezed states of the cavity radiation field in the two-atom one-mode model with multi-photon transitions is investigated. The time-dependent squeezing factors are calculated. The conditions for optimum squeezing are derived.</p></div>","PeriodicalId":101023,"journal":{"name":"Physica B+C","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0378-4363(88)90087-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76280729","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: 5
Dynamics of domain walls in hydrogen-bonded ferroelectrics 氢键铁电体畴壁动力学
Physica B+C Pub Date : 1988-06-01 DOI: 10.1016/0378-4363(88)90070-8
A. Gordon
{"title":"Dynamics of domain walls in hydrogen-bonded ferroelectrics","authors":"A. Gordon","doi":"10.1016/0378-4363(88)90070-8","DOIUrl":"10.1016/0378-4363(88)90070-8","url":null,"abstract":"<div><p>The solitonic mechanism for the protonic transfer is used to calculate a mobility of domain walls in hydrogen-bonded ferroelectrics. A one-dimensional model is considered. It is assumed that the sequence of proton jumps in double-minimum wells of hydrogen bonds brings about a domain wall motion. Calculations carried out for KH<sub>2</sub>PO<sub>4</sub> crystals can explain the high mobility of domain walls in these substances.</p></div>","PeriodicalId":101023,"journal":{"name":"Physica B+C","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0378-4363(88)90070-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87245707","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: 14
Effect of Jahn-Teller distortion on the exchange interactions in KCuF3. Two model studies jhn - teller畸变对KCuF3中交换相互作用的影响。两个模型研究
Physica B+C Pub Date : 1988-06-01 DOI: 10.1016/0378-4363(88)90067-8
Nobuko Fuchikami, Emile L. Bominaar, Ruud Block
{"title":"Effect of Jahn-Teller distortion on the exchange interactions in KCuF3. Two model studies","authors":"Nobuko Fuchikami,&nbsp;Emile L. Bominaar,&nbsp;Ruud Block","doi":"10.1016/0378-4363(88)90067-8","DOIUrl":"10.1016/0378-4363(88)90067-8","url":null,"abstract":"<div><p>In an analysis of the influence of the Jahn-Teller (JT) distortion in KCuF<sub>3</sub> on the exchange-coupling constants (ecc) along (<em>J</em><sub><em>S</em></sub> ≈ -190<em>K</em>), and perpendicular to (<em>J</em><sub><em>AS</em></sub> ≈ 0) the <em>c</em>-axis, two models are considered. First, a three-center, four-electron model is adopted with d(e<sub>g</sub>)- and p<sub>σ</sub>-orbitals at the cations and anion, respectively. Experimental values of ionization potentials and electron affinities are employed. The model accounts for the JT-distortion by using the induced admixtures of the e<sub>g</sub>-orbitals on the copper cations. The computations involve CI. Secondly, taking s-orbitals at all centers, we perform three-center, four-electron model calculations supplemented with two-anion non-additive exchange contributions obtained from four-center, six-electron model calculations. The latter contributions, strongly geometry dependent, account for the effect of JT-distortion on the ecc's. First-order exchange-perturbation theory is used. In the applications to KCuF<sub>3</sub> we adopt in the two models the same orbital parameterization, based on atomic properties, with which the ecc's in the regular perovskites KMF<sub>3</sub> : M = Mn, Co and Ni, are reproduced. The resulting values for <em>J</em><sub>S</sub> and <em>J</em><sub>AS</sub> agree with experiment. The vanishing value of <em>J</em><sub>AS</sub> is structural in the first (pd-) model and accidental in the second (s-) model. This discrepancy is discussed.</p></div>","PeriodicalId":101023,"journal":{"name":"Physica B+C","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0378-4363(88)90067-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78092402","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
Construction of liquidus curves of simple-eutectic binary alloys from Miedema theory 用Miedema理论构造简单共晶二元合金的液相曲线
Physica B+C Pub Date : 1988-06-01 DOI: 10.1016/0378-4363(88)90077-0
J.M. Lopez , J.A. Alonso , L.J. Gallego , M. Silbert
{"title":"Construction of liquidus curves of simple-eutectic binary alloys from Miedema theory","authors":"J.M. Lopez ,&nbsp;J.A. Alonso ,&nbsp;L.J. Gallego ,&nbsp;M. Silbert","doi":"10.1016/0378-4363(88)90077-0","DOIUrl":"10.1016/0378-4363(88)90077-0","url":null,"abstract":"<div><p>The liquidus curves of twenty five simple-eutectic binary alloys are constructed using the semi-empirical theory of heats of formation developed by Miedema and coworkers. Overall the predictions of this theory are quite correct. In cases where discrepancies exist, it is possible to improve the results by retaining the formal expression of the heat of formation proposed by Miedema, but modifying the prescribed values of the heats of solution.</p></div>","PeriodicalId":101023,"journal":{"name":"Physica B+C","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0378-4363(88)90077-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79616213","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
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