  Quantum tunneling effect has been an important issue in both fundamental
science and practical applications. Classical quantum tunneling devices are
generally rigid in structures which may encounter technical difficulties during
fabrication, functional tuning and shape adapting. Here through introducing the
room-temperature liquid metals as two conductive electrodes and a soft even
liquid insulating layer sandwiched between them, we proposed a conceptually
innovative all-soft or liquid quantum device which would help realize a couple
of unconventional quantum capabilities such as flexibility, deformability,
transformability, and reconfigurability, etc. which may not be easily offered
by a rigid quantum device. Representative structural configurations to make
such transformable quantum devices via sandwiching various liquid
metal-insulating layer-liquid metal (LM-IL-LM) components are suggested. The
feasibility for making such an all-soft quantum device is interpreted through
experimental evidences and theoretical evaluations. Potential future
applications of the proposed devices in a group of emerging fields including
intelligent quantum systems and quantum computing are prospected.
