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Evidencia de superfluidez en grupos de para-hidrógeno dentro de gotas de helio-4 a 0,15 grados Kelvin
1Max-Planck-Institut für Strömungsforschung, Bunsenstrabetae 10, 37073 Göttingen, Germany. General Physics Institute, Russian Academy of Sciences, 117942 Moscow, Russia.
Science (New York, N.Y.)
|September 1, 2000
Resumen
Este estudio utilizó la espectroscopia infrarroja para investigar las moléculas en las gotas de helio. Los resultados sugieren la primera evidencia de superfluidez en un líquido distinto del helio.
Área de la Ciencia:
- Fluidos y sólidos cuánticos.
- La espectroscopia es una técnica de espectroscopia.
- Física de bajas temperaturas Física de bajas temperaturas.
Sus antecedentes:
- La superfluidez es un fenómeno mecánico cuántico observado en el helio líquido.
- Comprender la superfluidez en otros sistemas puede revelar la física fundamental.
- Las gotas de helio proporcionan un entorno único para el estudio de los fenómenos cuánticos.
Objetivo del estudio:
- Para investigar el comportamiento de las moléculas de sulfuro de carbonilo (OCS) en helio-4 ((4) He) y gotas mixtas (4) He/(3) He.
- Para explorar la excitación del momento angular alrededor del eje OCS en diferentes ambientes de helio.
- Para proporcionar evidencia de superfluidez en un líquido más allá del helio.
Principales métodos:
- Se empleó la espectroscopia infrarroja para analizar las moléculas de OCS dopadas con para-hidrógeno (pH(2) o orto-deuterio (oD(2)).
- Los experimentos se llevaron a cabo en gotas de (4) He puras a 0,38 K y en gotas mixtas de (4) He/3) He a 0,15 K.
- Se monitorearon las características espectrales relacionadas con la excitación del momento angular.
Principales resultados:
- En las gotas de (4)He puras, las características espectrales indicaron el momento angular excitado tanto para pH(2) como para oD(2).
- En gotas más frías mezcladas (4)He/(3)He, estas características persistieron durante oD(2) pero desaparecieron para el pH(2).
- La desaparición de las características espectrales en el pH (((2) sugiere el cese de la excitación del momento angular.
Conclusiones:
- Los cambios observados en las características espectrales son consistentes con el inicio de la superfluidez en las gotas mixtas.
- Este estudio presenta la primera evidencia espectroscópica de superfluidez en un sistema líquido que no sea el helio.
- Los hallazgos abren nuevas vías para explorar los fenómenos cuánticos en nuevos entornos superfluidos.
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