Scope of Magnetic Tunnel Junction Based Molecular Electronics and   Spintronics Devices
  Dream of developing molecule-based logic and memory device is more than 70-year-old. Presently, molecule-based devices are also considered for quantum computation hardware. The recent studies have shown the molecule connected to metal leads can perform the qubit-based logic operation. This is an interesting question of why experimental progress is still very slow even when the scope of molecule-based devices may govern the advancement of next-generation logic and memory devices for the highest possible computer technologies. Molecules have the potential to be unmatched device elements as chemists can mass-produce an endless variety of molecules with novel optical, magnetic, and charge transport characteristics. However, the biggest challenge is to connect two metal leads to target molecules and develop a robust and versatile device fabrication technology that can be adopted for commercial-scale mass production. This paper discusses the distinct advantages of utilizing commercially successful magnetic tunnel junctions as a vehicle for developing molecular electronics and molecular spintronics devices. We describe the use of a tunnel junction with the exposed sides as a testbed for molecular devices. On the exposed sides of a tunnel, junction molecules are bridged across an insulator by chemically bonding with the two metal electrodes; sequential growth of metal-insulator-metal layers ensures that separation between two metal electrodes is controlled by the insulator thickness to the molecular device length scale. Here we also strongly emphasize a need for close collaboration between chemists and magnetic tunnel junction researchers. Such partnerships will have a strong potential to develop magnetic tunnel junction based molecular devices for the futuristic areas such as memory devices, magnetic metamaterials, and high sensitivity biosensors. 
Pawan Tyagi, Edwards Friebe, and Collin Baker
cond-mat.mtrl-sci cond-mat.mes-hall