U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications by: Katarina Cicak (Fed)

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 26 - 41 of 41

Low-loss superconducting resonant circuits using vacuum-gap -based microwave components

March 4, 2010
Author(s)
Katarina Cicak, Dale Li, Joshua Strong, Michael S. Allman, Fabio Altomare, Adam J. Sirois, Jed D. Whittaker, Raymond W. Simmonds
We have produced high quality resonant microwave circuits through developing a vacuum-gap technology for fabricating lumped-element capacitive and inductive components. We use micromachining to eliminate amorphous dielectric materials leaving vacuum in

Vacuum-Gap Capacitors for Low-Loss Superconducting Resonant Circuits

June 16, 2009
Author(s)
Katarina Cicak, Michael S. Allman, Joshua Strong, Kevin Osborn, Raymond W. Simmonds
Low-loss microwave components are used in many superconducting resonant circuits from multiplexed readouts of low-temperature detector arrays to quantum bits. Two-level system (TLS) defects in amorphous dielectric materials cause excess energy loss. In an

Electromagnetically induced transparency in a superconducting three-level system

April 16, 2009
Author(s)
Mika Sillanpaa, Katarina Cicak, Fabio Altomare, Jae Park, Raymond Simmonds, Jian Li, G. S. Paraoanu, Pertti Hakonen
When a three-level quantum system is irradiated by an intense coupling field resonant with two of the three possible transitions, the resonant absorption of the system from its ground state by an additional radiation field is suppressed. This effect, where

Elimination of two level fluctuators in superconducting quantum bits by an epitaxial tunnel barrier

September 7, 2006
Author(s)
Seongshik Oh, Katarina Cicak, Jeffrey S. Kline, Mika Sillanpaa, Jed D. Whittaker, Raymond W. Simmonds, David P. Pappas, Kevin Osborn
Quantum computing based on Josephson junction technology is considered promising due to its scalable architecture. However, decoherence is a major obstacle. Here, we report evidence for improved Josephson quantum bits qubits using a single-crystal Al2O3

Decoherence in Josephson Qubits from Dielectric Loss

November 16, 2005
Author(s)
John M. Martinis, Ken B. Cooper, Robert Mcdermott, Matthias Steffen, Markus Ansmann, Kevin Osborn, Katarina Cicak, Seongshik Oh, David P. Pappas, Raymond Simmonds, Clare Yu
Dielectric loss from two-level states is shown to be a dominant decoherence source in superconducting quantum bits. Depending on the qubit design, dielectric loss from insulating materials or the tunnel junction can lead to short coherence times. We show

Epitaxial growth of rhenium with sputtering

October 6, 2005
Author(s)
Seongshik Oh, Dustin P. Hite, Katarina Cicak, Kevin Osborn, Raymond W. Simmonds, Robert Mcdermott, Ken B. Cooper, Matthias Steffen, John M. Martinis, David P. Pappas
We have grown epitaxial renium (0001) films on α-Al 2O 3(0001) substrates using sputter deposition in an ultra high vacuum system. We find that better epitaxy is achieved with DC rather than with RF sputtering. With DC sputtering, epitaxy is obtained with

Low-Leakage Superconducting Tunnel Junctions with a Single-Crystal Al2O3 Barrier

September 5, 2005
Author(s)
Seongshik Oh, Katarina Cicak, Kevin Osborn, Raymond Simmonds, David P. Pappas, Robert Mcdermott, Ken B. Cooper, Matthias Steffen, John M. Martinis
We have developed a two-step growth scheme for single-crystal Al2O3 tunnel barriers. The barriers are epitaxially grown on single-crystal rhenium (Re) base electrodes that are grown epitaxially on a sapphire substrate, while polycrystalline Al is used as

Simultaneous state measurement of coupled Josephson phase qubits

February 25, 2005
Author(s)
Robert McDermott, Raymond Simmonds, Matthias Steffen, Ken B. Cooper, Katarina Cicak, Kevin Osborn, Seongshik Oh, David P. Pappas, John M. Martinis
One of the many challenges of building a scalable quantum computer is singleshot measurement of all the quantum bits (qubits). We have used simultaneous single-shot measurement of coupled Josephson phase qubits to directly probe interaction of the qubits