LTSS Lab
The Low Temperature Solid State lab consists of a class 100 clean room
thin film deposition lab, a clean room photolithography and electron beam
lithography (EBL) lab, and lab rooms for ongoing studies of superconducting
devices1. In the two clean room labs high quality Josephson
Junction devices are fabricated. A Josephson Juction is a tunnel
barrier between two superconducting materials which allows superconducting
current to flow up to a critical current without generating a voltage drop
across the barrier. This physical behavior is called the Josephson
effect. The Josephson effect in superconductors is the basis for
a variety of current projects on superconducting devices, for instance,
submillimeter wave radiation sources and mixers, and a new class of digital
electronics (called Rapid Single Flux Quantum Logic) which can operate
at frequencies of over 100 GHz, that is, more than 100 times faster than
present semiconductor logic circuits (RSFQ
WWW page). The Josephson effect is also used for the study of
several fundamental physics problems such as the quantum mechanics of macroscopic
variables. Another project has the goal of developing a useful and
reproducible thin-film Josephson junction made of high-temperature superconductors
(HTS). This project combines the physics of Josephson tunneling in HTS,
materials aspects, and cutting edge electron beam lithography on a scale
of less than 10 nm. Stony Brook researchers have recently demonstrated
an all-HTS RSFQ circuit operating at temperatures of up to 30K.
The LTSS lab is headed by professor James
Lukens of Stony Brook's Condensed Matter group and is run by his talented
staff of post-docs, technitians, and graduate students. Here are
some pictures from James Lukens LTSS lab at Stony Brook.
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Graduate student Wenxing Zhang working with the electron beam lithography
system in Prof. Lukens' laboratory to fabricate submillimeter wave oscillators
based on the Josephson effect. The system can pattern devices with dimensions
of less than 30 nm.* |
| Prof. James Lukens and graduate student Richard Rouse examining the
niobium trilayer deposition system, which is a central tool in the laboratory
for the fabrication of multilevel superconducting circuits and devices.* |
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*Photos ©1996 Eric Michelson; all rights reserved.
1 Some text here was obtained from the Condensed
Matter website at the Stony Brook Physics Department.
