On the Origin of a Small Hole Pocket in the Fermi Surface of Underdoped YBa2Cu3O
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The Fermi surface structure of a layered organic superconductor β″-(BEDT-TTF)2SF5CH2CF2SO3 was determined by angular-dependent magnetoresistance oscillations measurements and band-structure calculations. This salt was found to have two small pockets with the same area: a deformed square hole pocket and an elliptic electron pocket. Characteristic corrugations in the field dependence of the interlayer resistance in the superconducting phase were observed at any in-plane field directions. The features were ascribed to the commensurability (CM) effect between the Josephson vortex lattice and the periodic nodal structure of the superconducting gap in the Fulde–Ferrell–Larkin–Ovchinnikov (FFLO) phase. The CM effect was observed in a similar field region for various in-plane field directions, in spite of the anisotropic nature of the Fermi surface. The results clearly showed that the FFLO phase stability is insensitive to the in-plane field directions.

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High Field Magnetoresistance and Quantum Oscillations in Iron Whiskers

Canadian Journal of Physics ◽

10.1139/p75-038 ◽

1975 ◽

Vol 53 (3) ◽

pp. 284-298 ◽

Cited By ~ 10

Author(s):

M. A. Angadi ◽

E. Fawcett ◽

Mark Rasolt

Keyword(s):

Fermi Surface ◽

High Field ◽

Quantum Oscillations ◽

Hole Pocket ◽

Strain Dependence ◽

Magnetic Breakdown ◽

Minority Spin ◽

Iron Whiskers ◽

Lower Frequencies

[100] and [111] iron whiskers were measured to determine the origin of open orbits responsible for anisotropy of the high field magnetoresistance. The marked strain dependence of the minima resulting from [Formula: see text] open orbits permits their unambiguous identification as resulting from magnetic breakdown at a symmetry degeneracy, de Haas–Shubnikov oscillations were observed, and complementary de Haas–van Alphen measurements showed the lower frequencies (in the range 1.2–1.5 MG) to correspond to a hole pocket of the minority spin Fermi surface.

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Experimental Evidence for theX2↓Hole Pocket in the Fermi Surface of Ni from Magnetic Crystalline Anisotropy

Physical Review Letters ◽

10.1103/physrevlett.40.344 ◽

1978 ◽

Vol 40 (5) ◽

pp. 344-346 ◽

Cited By ~ 36

Author(s):

R. Gersdorf

Keyword(s):

Fermi Surface ◽

Experimental Evidence ◽

Hole Pocket ◽

Crystalline Anisotropy

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Evolution of the Fermi surface geometry in high Tc superconductors: from small hole pockets to a large tight binding Fermi surface

Physica C Superconductivity ◽

10.1016/s0921-4534(98)00056-2 ◽

1998 ◽

Vol 301 (1-2) ◽

pp. 85-91 ◽

Cited By ~ 1

Author(s):

Bumsoo Kyung

Keyword(s):

Fermi Surface ◽

Tight Binding ◽

Small Hole ◽

High Tc Superconductors ◽

Surface Geometry ◽

High Tc

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Advanced TEM sample preparation techniques for submicron Si devices

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138956 ◽

1995 ◽

Vol 53 ◽

pp. 516-517 ◽

Cited By ~ 1

Author(s):

P. B. Basham ◽

H. L. Tsai

Keyword(s):

Sample Preparation ◽

Process Development ◽

Light Transmission ◽

Specific Area ◽

Turnaround Time ◽

Small Hole ◽

Area Of Interest ◽

Transmission Electron ◽

Polished Side ◽

Preparation Techniques

The use of transmission electron microscopy (TEM) to support process development of advanced microelectronic devices is often challenged by a large amount of samples submitted from wafer fabrication areas and specific-spot analysis. Improving the TEM sample preparation techniques for a fast turnaround time is critical in order to provide a timely support for customers and improve the utilization of TEM. For the specific-area sample preparation, a technique which can be easily prepared with the least amount of effort is preferred. For these reasons, we have developed several techniques which have greatly facilitated the TEM sample preparation.For specific-area analysis, the use of a copper grid with a small hole is found to be very useful. With this small-hole grid technique, TEM sample preparation can be proceeded by well-established conventional methods. The sample is first polished to the area of interest, which is then carefully positioned inside the hole. This polished side is placed against the grid by epoxy Fig. 1 is an optical image of a TEM cross-section after dimpling to light transmission.

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