TY - JOUR
T1 - A ballistic graphene superconducting microwave circuit
AU - Schmidt, Felix E.
AU - Jenkins, Mark D.
AU - Watanabe, Kenji
AU - Taniguchi, Takashi
AU - Steele, Gary A.
PY - 2018
Y1 - 2018
N2 - Josephson junctions (JJ) are a fundamental component of microwave quantum circuits, such as tunable cavities, qubits, and parametric amplifiers. Recently developed encapsulated graphene JJs, with supercurrents extending over micron distance scales, have exciting potential applications as a new building block for quantum circuits. Despite this, the microwave performance of this technology has not been explored. Here, we demonstrate a microwave circuit based on a ballistic graphene JJ embedded in a superconducting cavity. We directly observe a gate-tunable Josephson inductance through the resonance frequency of the device and, using a detailed RF model, we extract this inductance quantitatively. We also observe the microwave losses of the device, and translate this into sub-gap resistances of the junction at μeV energy scales, not accessible in DC measurements. The microwave performance we observe here suggests that graphene Josephson junctions are a feasible platform for implementing coherent quantum circuits.
AB - Josephson junctions (JJ) are a fundamental component of microwave quantum circuits, such as tunable cavities, qubits, and parametric amplifiers. Recently developed encapsulated graphene JJs, with supercurrents extending over micron distance scales, have exciting potential applications as a new building block for quantum circuits. Despite this, the microwave performance of this technology has not been explored. Here, we demonstrate a microwave circuit based on a ballistic graphene JJ embedded in a superconducting cavity. We directly observe a gate-tunable Josephson inductance through the resonance frequency of the device and, using a detailed RF model, we extract this inductance quantitatively. We also observe the microwave losses of the device, and translate this into sub-gap resistances of the junction at μeV energy scales, not accessible in DC measurements. The microwave performance we observe here suggests that graphene Josephson junctions are a feasible platform for implementing coherent quantum circuits.
UR - http://resolver.tudelf.nl/uuid:ff75b1b7-4110-4a4f-b7a7-1ae00f40f9f7
UR - http://www.scopus.com/inward/record.url?scp=85054428609&partnerID=8YFLogxK
U2 - 10.1038/s41467-018-06595-2
DO - 10.1038/s41467-018-06595-2
M3 - Article
C2 - 30287816
AN - SCOPUS:85054428609
SN - 2041-1723
VL - 9
JO - Nature Communications
JF - Nature Communications
IS - 1
M1 - 4069
ER -