摘要:

We have developed the superfluid analog of the superconducting rf SQUID. Such a device is a quantum mechanically based, absolute gyroscope and has been used to sense the rotation of the Earth. Our device is fabricated using silicon processing techniques and forms a planer sensing loop of superfluid helium which couples to the applied rotation. A much more sensitive superfluid gyroscope based on the principle’s demonstrated with this device, might ultimately be used to detect the precession of our local inertial frame with respect to the fixed stars by the gravitomagnetic field of the rotating Earth. We compare the superfluid gyroscope against two other experiments aimed at detecting this general relativistic effect. ©1998 American Institute of Physics.

ISSN:1063-777X    

DOI:10.1063/1.593549

出版商:AIP    

年代:1998

数据来源: AIP

ISSN:1063-777X    

DOI:10.1063/1.593550

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

In recent years, there has been significant interest in the laser manipulation of neutral atoms, and specifically in the use of light fields to manipulate not only the internal but also the external coordinates of an atom. Among the most dramatic results of this work have been the production of dense ultra-cold samples of trapped neutral atoms. These samples have been used to expand the horizons of fundamental physics and have made possible significant advancements in metrology. Furthermore, the ability to manipulate atomic motion with light has helped to create entirely new fields of research such as atom optics where matter wave analogues of light wave systems are investigated and optical where light is used to create a periodic array of atoms similar to crystals. ©1998 American Institute of Physics.

ISSN:1063-777X    

DOI:10.1063/1.593551

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

The evolution of shape of the surface of equipotentially charged liquid hydrogen film condensed on the lower or upper plate of a horizontally placed diode in external electric fields has been studied experimentally under the condition of total compensation of the applied field by the surface charge. Reconstruction phenomenon—the formation of a solitary wave (soliton)—has been observed in an electric field higher than some critical value for the film that covers the lower plate. ©1998 American Institute of Physics.

ISSN:1063-777X    

DOI:10.1063/1.593552

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

A promising way to investigate2Dcontact phenomena is proposed. This method is based on the idea of depositing surface state electrons (SSE) on a thin layer of liquid helium covering the surface of a solid sample containing a2Dcharge carrier system. The density of SSE adjusts to screen contact-induced perturbations of the electrostatic potential across the sample. As a result, the helium layer thickness varies due to the variation of the electrostatic pressure, thus providing a map. This map may be read off interferometrically by a technique already employed for the investigation of multi-electron dimples on helium. We have realized this mapping for a structured electrode as a test sample to demonstrate the resolution of the method. ©1998 American Institute of Physics.

ISSN:1063-777X    

DOI:10.1063/1.593553

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

We describe the opportunities for improved scientific understanding and technical manipulation of cryogenic fluids, particularly molecular hydrogen, by the use of carefully designed magnetic field configurations produced with assemblies of permanent magnets. We discuss the levitation of hydrogen in order to perfect technical means for handling this and other cryogenic fluids. The development of the techniques to be explored here provide extraordinary opportunities for improved methods for handling rocket fuels and cryogenic fluids in low gravity environments. ©1998 American Institute of Physics.

ISSN:1063-777X    

DOI:10.1063/1.593554

出版商:AIP    

年代:1998

数据来源: AIP

ISSN:1063-777X    

DOI:10.1063/1.593555

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

Superfluid phases of3Heare quantum liquids with the interacting fermionic and bosonic fields. In many respects they can simulate the interacting quantum fields in the physical vacuum. One can observe analogs of such phenomena as axial anomaly, vacuum polarization, zero-charge effect, fermionic charge of the vacuum, baryogenesis, ergoregion, vacuum instability, etc. We discuss some topics using as an example several linear defects in3He-A:(1) disgyration, which simulates the extremely massive cosmic string, (2) singular vortex, which is analogous to the spinning cosmic string, and (3) continuous vortex, whose motion causes the «momentogenesis» which is the analog of baryogenesis in early Universe. The production of the fermionic momentum by the vortex motion (the counterpart of the electroweak baryogenesis) has been recently measured in Manchester experiments on rotating superfluid3He-Aand3He-B.To simulate the other phenomena, one needs a rather low temperature and high homogeneity, which probably can be attained under microgravity conditions. ©1998 American Institute of Physics.

ISSN:1063-777X    

DOI:10.1063/1.593556

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

The theory of a nonideal gas developed by N. N. Bogoliubov is applied for a semiclassical description of nonlinear dynamics of Bose condensate density. Analytical calculations lead to temperature dependence of heat capacityCvtypical of superfluid4Heat temperatures below and above the superconducting transition temperatureTcexcept for the interval1.6 K<T<2.2 K. ©1998 American Institute of Physics.

ISSN:1063-777X    

DOI:10.1063/1.593557

出版商:AIP    

年代:1998

数据来源: AIP

ISSN:1063-777X    

DOI:10.1063/1.593558

出版商:AIP    

年代:1998

数据来源: AIP