COULOMB BLOCKADE-BASED NANOTHERMOMETRY IN STRONG MAGNETIC-FIELDS

We have performed experiments to test for the susceptibility to strong magnetic fields of electron tunneling in normal metal-based nanostruc tures for Coulomb blockade primary thermometry. We have confirmed that , to within our accuracy of about +/-1%, the single electron charging- induced zero bias differential resistance maximum is unaffected by the field up to 23 T at temperatures of 0.4-4.2 K. We discuss the simple theoretical basis of this immunity. We also report on the practical li mitation at low temperatures imposed by superconductivity of aluminium in small magnetic fields. (C) 1998 American Institute of Physics.