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El impacto de la superconductividad a alta temperatura en los magnetómetros SQUID
Science (New York, N.Y.)
|October 14, 1988
Resumen
Los dispositivos de interferencia cuántica superconductores (SQUID) ofrecen una detección ultrasensible. Los SQUID superconductores de alta temperatura proporcionan comodidad, pero tienen un rendimiento de ruido más bajo en comparación con los dispositivos de baja temperatura.
Área de la Ciencia:
- Física Física es la física de las cosas.
- Ciencia de los materiales Ciencia de los materiales.
- Ingeniería Eléctrica Ingeniería Eléctrica.
Sus antecedentes:
- Los dispositivos de interferencia cuántica superconductores (SQUID) son detectores ultrasensibles utilizados en varias aplicaciones.
- Temperatura de transición baja (T(c)) superconductor SQUIDs operan a temperaturas de helio líquido.
- Los SQUIDs superconductores de alto T (c) ofrecen una comodidad operativa a temperaturas de nitrógeno líquido (77 K).
Objetivo del estudio:
- Para comparar el rendimiento de los magnetómetros basados en SQUID con otros tipos de magnetómetros.
- Evaluar las compensaciones entre la comodidad y el rendimiento acústico en la tecnología SQUID.
Principales métodos:
- Fabricación de SQUIDs de CC y RF utilizando superconductores de baja y alta T.
- Funcionamiento de los SQUID a temperaturas de helio líquido y nitrógeno líquido.
- Análisis comparativo de las resoluciones del magnetómetro.
Principales resultados:
- Los SQUID de alta T (c) exhiben un rendimiento de ruido más pobre, especialmente a bajas frecuencias, en comparación con los SQUID de baja T (c).
- Los magnetómetros basados en SQUID se comparan con los magnetómetros de temperatura ambiente con respecto a la resolución.
Conclusiones:
- La elección entre T bajo y alto (c) SQUID depende de los requisitos de la aplicación para la sensibilidad frente a la comodidad operativa.
- La investigación adicional puede centrarse en la mejora del rendimiento acústico de los SQUID de alto T.
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