Gate-Tunable Superconductor-Semiconductor Parametric Amplifier

Gate-tunable kinetic inductance parametric amplifier

“…We find K ≈ 20 kHz for all gate voltages, which lies between typical values reported for parametric amplifiers based on a single junction [36] and for kinetic-inductancebased amplifiers [39]. The flat response versus gate voltage facilitates a robust tune-up of the device in contrast to previous voltage-tunable junction-based systems, where the Kerr coefficient strongly depends on the gate voltage [36][37][38]. The internal quality factor increases slightly over the accessible gate-voltage range starting at Q i ∼ 4000, whereas the coupling quality factor stays nearly constant at Q c ∼ 50.…”

“…Recent technological advances in the integration of exotic heterostructures into superconducting circuits, such as hybrid superconducting-semiconducting nanostructures [15,[27][28][29][30][31][32], graphene Josephson junctions [19,33,34], or carbon-nanotube junctions [35], have enabled the realization of electrostatic control of supercurrents in superconducting circuits. This additional method of tunability has already opened up new avenues to build novel types of parametric amplifiers from graphene [36,37] and proximitized semiconductors [38], further advancing the development of densely packed superconducting electronics due to minimal crosstalk. Concurrently, magnetic field compatibility of parametric amplifiers has been achieved through the use of superconducting thin films acting as kinetic inductance material [39][40][41].…”

Parity-conserving Cooper-pair transport and ideal superconducting diode in planar germanium

“…III–V semiconductors have become the materials of choice for realizing high-quality hybrid devices, due to the possibility of growing epitaxial Al on top of them 1 . Gate-tunable superconducting and Andreev spin qubits 2 – 6 , parametric amplifiers 7 , highly efficient Cooper pair splitters 8 – 10 and a minimal Kitaev chain 11 are prominent examples of what has been achieved in the past decade. In addition, non-reciprocal devices, such as superconducting diodes have attracted a lot of interest 12 , especially in Josephson junctions in the presence 13 – 15 or absence 16 – 18 of a Zeeman field and in multiterminal devices 19 , 20 .…”

Demonstration of the Nonlocal Josephson Effect in Andreev Molecules

“…The development of high-quality hybrid superconductor–semiconductor materials over the past decade enabled new possibilities in superconducting electronics and quantum computing. − In particular, Andreev bound states (ABSs) − arising in superconductor–semiconductor–superconductor Josephson junctions (JJs) − offer functionalities not attainable in metallic JJs. A prominent example is the electrostatic tuning of the critical current, ,, which allows for JJ field-effect transistors, − voltage-tunable superconducting qubits, − resonators, , and amplifiers. − Moreover, the interplay between ABSs, spin–orbit interaction, and Zeeman fields results in nonreciprocal switching currents − and anomalous phase offsets, or φ 0 -junctions, − with applications in superconducting electronics and spintronics . A yet largely unexplored possibility offered by superconductor–semiconductor hybrids is the engineering of Andreev molecules from the hybridization of spatially overlapping ABSs. − Predicted to arise in JJs coupling over length scales comparable to the superconducting coherence length, Andreev molecules offer a promising platform to realize φ 0 -junctions and novel manipulation and coupling schemes for Andreev qubits .…”

“…A prominent example is the electrostatic tuning of the critical current, 3 , 11 , 12 which allows for JJ field-effect transistors, 13 − 16 voltage-tunable superconducting qubits, 17 − 20 resonators, 21 , 22 and amplifiers. 23 − 25 Moreover, the interplay between ABSs, spin–orbit interaction, and Zeeman fields results in nonreciprocal switching currents 26 − 29 and anomalous phase offsets, or φ 0 -junctions, 30 − 38 with applications in superconducting electronics and spintronics. 39 A yet largely unexplored possibility offered by superconductor–semiconductor hybrids is the engineering of Andreev molecules from the hybridization of spatially overlapping ABSs.…”