Ultra-Efficient Superconducting Dayem Bridge Field-Effect Transistor.
Nano Lett
; 18(7): 4195-4199, 2018 07 11.
Article
en En
| MEDLINE
| ID: mdl-29894197
Superconducting field-effect transitor (SuFET) and Josephson field-effect transistor (JoFET) technologies take advantage of electric-field-induced control of charge-carrier concentration to modulate the channel superconducting properties. Despite the fact that the field-effect is believed to be ineffective for superconducting metals, recent experiments showed electric-field-dependent modulation of the critical current ( IC) in a fully metallic transistor. However, the grounding mechanism of this phenomenon is not completely understood. Here, we show the experimental realization of Ti-based Dayem bridge field-effect transistors (DB-FETs) able to control the IC of the superconducting channel. Our easy fabrication process for DB-FETs show symmetric full suppression of IC for applied critical gate voltages as low as VGC ≃ ±8 V at temperatures reaching about the 85% of the record critical temperature, TC ≃ 550 mK, for titanium. The gate-independent TC and normal-state resistance ( RN) coupled with the increase of resistance in the superconducting state ( RS) for gate voltages close to the critical value ( VGC) suggest the creation of field-effect induced metallic puddles in the superconducting sea. Our devices show extremely high values of transconductance (| gmMAX| ≃ 15 µA/V at VG ≃ ±6.5 V) and variations of Josephson kinetic inductance ( LK) with VG of 2 orders of magnitude. Therefore, the DB-FET appears as an ideal candidate for the realization of superconducting electronics, superconducting qubits, and tunable interferometers as well as photon detectors.
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Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
Nano Lett
Año:
2018
Tipo del documento:
Article
País de afiliación:
Italia
Pais de publicación:
Estados Unidos