|
Records |
Links |
|
Author |
Santhanam, P.; Wind, S.; Prober, D. E. |
|
|
Title |
Localization, superconducting fluctuations, and superconductivity in thin films and narrow wires of aluminum |
Type |
Journal Article |
|
Year |
1987 |
Publication |
Phys. Rev. B |
Abbreviated Journal |
Phys. Rev. B |
|
|
Volume |
35 |
Issue |
7 |
Pages |
3188-3206 |
|
|
Keywords |
Al films; electron-phonon scattering; electron-electron scattering; Disordered structures; amorphous and glassy solids, Relaxation times and mean free paths, Galvanomagnetic and other magnetotransport effects |
|
|
Abstract |
We report a comprehensive set of experiments on wide and narrow thin-film strips of aluminum which test the predictions of recent localization theory. The experiments on wide films in the two-dimensional regime confirm the theoretical predictions and also yield insight into inelastic mechanisms and spin-orbit scattering rates. Our extension of the existing theory for one-dimensional systems to include spin-orbit scattering and Maki-Thompson superconducting fluctuations is verified by the experiments. We find clear evidence for one-dimensional localization, with inferred inelastic rates identical to those in two-dimensional films. The prediction of the localization theory for a dimensional crossover from two-dimensional to one-dimensional behavior is also confirmed. We have reanalyzed the results of some previous experiments on thin films and narrow wires in light of these results. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
|
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
|
Approved |
no |
|
|
Call Number |
RPLAB @ gujma @ |
Serial |
757 |
|
Permanent link to this record |
|
|
|
|
Author |
Siddiqi, I.; Prober, D. E. |
|
|
Title |
Nb–Au bilayer hot-electron bolometers for low-noise THz heterodyne detection |
Type |
Journal Article |
|
Year |
2004 |
Publication |
Applied Physics Letters |
Abbreviated Journal |
Appl. Phys. Lett. |
|
|
Volume |
84 |
Issue |
8 |
Pages |
1404 |
|
|
Keywords |
HEB, mixers, dynamic range, saturation, LO power, local oscillator power, Nb |
|
|
Abstract |
The sensitivity of present Nb diffusion-cooled hot-electron bolometer (HEB) mixers is not quantum limited, and can be improved by reducing the superconducting transition temperature TC. Lowering TC reduces thermal fluctuations, resulting in a decrease of the mixer noise temperature TM. However, lower TC mixers have reduced dynamic range and saturate more easily due to background noise. We present 30 GHz microwave measurements on a bilayer HEB system, Nb–Au, in which TC can be tuned with Au layer thickness to obtain the maximum sensitivity for a given noise background. These measurements are intended as a guide for the optimization of THz mixers. Using a Nb–Au mixer with TC = 1.6 K, we obtain TM = 50 K with 2 nW of local oscillator (LO) power. Good mixer performance is observed over a wide range of LO power and bias voltage and such a device should not exhibit saturation in a THz receiver. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0003-6951 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
|
Approved |
no |
|
|
Call Number |
|
Serial |
571 |
|
Permanent link to this record |