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Displaying 1 - 7 of 7

Targeted enrichment of 28Si thin films for quantum computing

March 9, 2020
Author(s)
Ke Tang, Hyun S. Kim, Aruna N. Ramanayaka, David S. Simons, Joshua M. Pomeroy
We report on the growth of isotopically enriched 28Si epitaxial films with precisely controlled enrichment levels, ranging from natural abundance ratio of 92.2% all the way to 99.99987 % (0.832 × 10-6 mol/mol 29Si). Isotopically enriched 28Si is regarded

Use of quantum effects as potential qualifying metrics for "quantum grade silicon"

December 30, 2019
Author(s)
Aruna N. Ramanayaka, Ke Tang, Joseph A. Hagmann, Hyun S. Kim, David S. Simons, Curt A. Richter, Joshua M. Pomeroy
Across solid state quantum information, material deficiencies limit performance through enhanced relaxation, charge defect motion, or isotopic spin noise. While classical measurements of device performance provide cursory guidance, specific qualifying

A compact, UHV ion source for enriching 28Si and depositing epitaxial thin films

August 22, 2019
Author(s)
Ke Tang, Hyun S. Kim, Aruna N. Ramanayaka, David S. Simons, Joshua M. Pomeroy
An ultra-high-vacuum (UHV) compatible Penning ion source for growing pure, highly enriched 28Si epitaxial thin films is presented. Enriched 28Si is a critical material for quantum information due to the elimination of nuclear spins and, in some cases, must

Magnetotransport in highly enriched 28Si for quantum information processing devices

November 25, 2018
Author(s)
Aruna N. Ramanayaka, Ke Tang, Joseph Hagmann, Hyun S. Kim, Curt A. Richter, Joshua M. Pomeroy
Elimination of unpaired nuclear spins can result in low error rates for quantum computation; therefore, isotopically enriched 28Si is regarded as an ideal environment for quantum information processing devices. Using mass selected ion beam deposition

Towards superconductivity in p-type delta-doped Si/Al/Si heterostructures

July 30, 2018
Author(s)
Aruna N. Ramanayaka, Hyun Soo Kim, Joseph A. Hagmann, Roy E. Murray, Ke Tang, Neil M. Zimmerman, Curt A. Richter, Joshua M. Pomeroy, Frederick Meisenkothen, Huairuo Zhang, Albert Davydov, Leonid A. Bendersky
In pursuit of superconductivity in p-type silicon (Si), we are using a single atomic layer of aluminum (Al) sandwiched between a Si substrate and a thin Si epi-layer. The delta layer was fabricated starting from an ultra high vacuum (UHV) flash anneal of

STM patterned nanowire measurements using photolithographically defined implants in Si(100)

January 29, 2018
Author(s)
Aruna N. Ramanayaka, Hyun Soo Kim, Ke Tang, Xiqiao Wang, Richard M. Silver, Michael D. Stewart, Joshua M. Pomeroy
Using photolithographically defined implant wires for electrical connections, we demonstrate measurement of a scanning tunneling microscope (STM) patterned nanoscale electronic device on Si(100), eliminating the onerous alignment procedures and electron

Enriching and purifying silicon epilayers for quantum information

December 6, 2016
Author(s)
Joshua M. Pomeroy, Kevin J. Dwyer, Ke Tang, Hyun S. Kim, Aruna N. Ramanayaka, David S. Simons
High quality, enriched silicon contains an exceptionally low density of defects and unpaired electron and nuclear spins that allow candidate qubits (single donors or quantum dots) to exhibit very long dephasing times compared to silicon with a natural