Pa. Fisher et al., High-power on-chip microrefrigerator based on a normal-metal/insulator/superconductor tunnel junction, APPL PHYS L, 74(18), 1999, pp. 2705-2707
We present measurements and theoretical modeling of two normal/insulator/su
perconductor tunnel junction microrefrigerators. The first device, fabricat
ed on a thick silicon substrate, had a cooling power of 36 pW, an active vo
lume of 350 mu m(3), and a temperature drop for electrons of 2 mK from a 30
0 mK bath. The second device, fabricated on a thin silicon nitride membrane
, had a cooling power of 4 pW and cooled both electrons and phonons in a si
milar volume by almost 2 mK from a bath of 300 mK. These are the largest co
oling powers and active volumes for electron and phonon refrigeration repor
ted to date. (C) 1999 American Institute of Physics. [S0003-6951(99)04818-4
].