5. SQUID electronics
SQUIDs are solid
state device like transistors and
resistors. Usually SQUID are operated in the presence of magnetic field
and it
produces a frequency in the order of several MHz for few micro volts
when
applied across the junctions. So it can be used like an amplifier. NIST
have
demonstrated experimentally with identical input coils connected in
series with
100-SQUID arrays producing very large bandwidth about 100 MHz. In
analogy with
LCR circuits when a dc SQUID is connected to inductance L and shunt
resistor R a
relaxation oscillation are produced. SQUIDs are also used in
constructing
Quantum logic gates [6]. This is just because of its quantum mechanical
character.